c/EPA United States Environmental Protection Agency Environmental Research Laboratory Athens GA 3061 3 EPA-600/6-82-004b September 1982 Research and Development Water Quality Assessment: A Screening Procedure for Toxic and Conventional Pollutants—Part 2 ------- EPA-600/6-82-0045 September 1982 WATER QUALITY ASSESSMENT: A Screening Procedure for Toxic and Conventional Pollutants Part 2 by W.B. Mills, J.D. Dean, D.B. Porcella, S.A. Gherini, R.J.M. Hudson, W.E. Frick, G.L. Rupp, and G.L. Bowie Tetra Tech, Incorporated Lafayette, California 94549 Contract No. 68-03-2673 Prepared in Cooperation with U.S. EPA's Center for Water Quality Modeling Environmental Research Laboratory Athens, Georgia Monitoring and Data Support Division Office of Water Regulations and Standards Office of Water Washington, D.C. Technology Transfer Center for Environmental Research Information Cincinnati, Ohio ENVIRONMENTAL RESEARCH LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY ATHENS, GEORGIA 30613 -....v^^Tvf.qj protection Agency ",-iv (5PL-16) < n;:1:: Street, Boom 1670 ii, 60604 ------- DISCLAIMER Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Environmental Protection Agency. n ------- ABSTRACT New technical developments in the field of water quality assessment and a reordering of water quality priorities prompted a revision of Water Quality Assessment: A Screening Methodology for Mondesignated 208 Areas (EPA-600/9-77-023).The utility of the revised manual is enhanced by the inclusion of information on the accumulation, transport, and fate of toxic chemicals in the environment. The new subtitle—A Screening Procedure for Toxic and Conventional Pollutants—reflects the added information. Applying the manual's simple techniques, the user is now capable of assessing the loading and fate of conventional pollutants (temperature, biochemical oxygen demand-dissolved oxygen, nutrients, and sediments) and toxic pollutants (from the U.S. EPA list of priority pollutants) in streams, impoundments, and estuaries. The techniques are readily programmed on hand- held calculators. Most of the data required for using these procedures are contained in the manual. Because of its size, the manual has been divided into three parts. Part 1 contains the introduction and chapters on the aquatic fate of toxic organic substances, waste load calculations, and the assessment of water quality para- meters in rivers and streams. Part 2 continues with chapters on the assessment of impoundments and estuaries and appendices A, B, C, E, F, G and H. Appendix D is provided in the third part (on microfiche in the EPA-printed manual). This report is submitted in fulfillment of Contract No. 68-03-2673 by Tetra Tech, Inc., under the sponsorship of the U.S. Environmental Protection Agency. Work was completed as of February 1982. ------- TABLE OF CONTENTS PART 2 Page DISCLAIMER ii ABSTRACT iii LIST OF FIGURES (PART 2) vi LIST OF TABLES (PART 2) x CHAPTER 5 IMPOUNDMENTS 1 5.1 Introduction 1 5.2 Impoundment Stratification 3 5.3 Sediment Accumulation 24 5.4 Eutrophication and Control 65 5.5 Impoundment Dissolved Oxygen 92 5.6 Toxic Chemical Substances 128 5.7 Application of Methods and Example Problem 140 References for Chapter 5 185 Glossary of Terms 187 6 ESTUARIES 191 6.1 Introduction 191 6.2 Estuarine Classification 207 6.3 Flushing Time Calculations 222 6.4 Far Field Approach to Pollutant Distribution in Estuaries 251 6.5 Pollutant Distribution following Discharge from a Marine 314 Outfall 6.6 Thermal Pollution 367 6.7 Turbidity 379 6.8 Sedimentation 390 References for Chapter 6 408 APPENDICES A Monthly Distribution of Rainfall Erosivity Factor R A-l B Methods for Predicting Soil Erodibility Index K B-l C Stream and River Data C-l D Impoundment Thermal Profiles D-l iv ------- APPENDICES (continued) E Modeling Thermal Stratification in Impoundments F Reservoir Sediment Deposition Surveys 6 Initial Dilution Tables H Equivalents of Commonly Used Units of Measurement ------- LIST OF FIGURES ' PART 2 Figure Page V-1 Water Density as a Function of Temperature and Dissolved Solids 4 Concentration V-2 Water Flowing into an Impoundment Tends to Migrate toward a Region 5 of Similar Density V-3 Annual Cycle of Thermal Stratification and Overturn in an Im- 6 poundment V-4 Thermal Profile Plots Used in Example V-1 19 V-5 Thermal Profile Plots Appropriate for use in Example V-2 23 V-6 Sediment Rating Curve Showing Suspended Sediment Discharge as a 27 Function of Flow V-7 Relationship between the Percentage of Inflow-Transported Sedi- 29 ment Retained within an Impoundment and Ratio of Capicity to Inflow V-8 Plot of C/R and CR2 Versus R 34 V-9 Drag Coefficient (C) as Function of Reynold's Number (R) and Par- 35 tide Shape V-10 Schematic Representation of Hindered Settling of Particles in 36 Fluid Column V-ll Velocity Correction Factor for Hindered Settling 38 V-12 Upper and Lo er Lakes and Environs, Long Island, New York 43 V-13 Impoundment Configurations Affecting Sedimentation 47 V-14 Kellis Pond and Surrounding Region, Long Island, New York 50 V-15 Hypothetical Depth Profiles for Kellis Pond 51 V-16 Hypothetical Flow Pattern in Kellis Pond 52 VI ------- Figure Page V-17 Hypothetical Depth Profiles for Kellis Pond Not Showing Signi- 53 cant Shoaling V-18 Lake Owyhee and Environs 55 V-19 New Mi 11 pond and Environs. New Mill pond is Subdivided for Pur- 56 poses of Estimating Sedimentation in Regions A, B, and C V-20 Significance of Depth Measures D, D1 , and D11 , and the Assumed 59 Sedimentation Pattern V-21 Settling Velocity for Spherical Particles 60 V-22 Nomograph for Estimating Sediment Trap Efficiency 61 V-23 Formulations for Evaluating Management Options for Pollutants 70 in Lakes and Reservoirs V-24 US OECD Data Applied to Vollenweider (1976) Phosphorus Loading 72 and Mean Depth/Hydraulic Residence Time Relationship V-25 Relationship between Summer Chlorophyll and Spring Phosphorus 79 V-26 Maximal Primary Productivity as a Function of Phosphate Concen- 80 tration V-27 Conceptualization of Phosphorus Budget Modeling 85 V-28 Typical Patterns of Dissolved Oxygen in Hyrum Reservoir 93 V-29 Geometric Representation of a Stratified Impoundment 96 V-30 Quality and Ecologic Relationships 97 V-31 Rate of BOD Exertion at Different Temperatures Showing the First 102 and Second Deoxygenation Stages V-32 Quiet Lake and Environs 114 V-33 Thermal Profile Plots for Use in Quiet Lake Example 122 V-34 Nomograph for Estimating Sediment Trap Efficiency 141 V-35 Generalized Schematic of Lake Computations 147 V-36 The Occoquan River Basin 148 V-37 Thermal Profile Plots for Occoquan Reservoir 152 ------- Figure Page V-38 Summary of Reservoir Sedimentation Surveys Made in the United 155 States through 1970 V-39 Dissolved Oxygen Depletion Versus Time in the Occoquan Reservoir 180 VI-1 Typical Main Channel Salinity and Velocity for Strati ied Estu- 196 aries VI-2 Typical Main Channel Salinity and Velocity Profiles for Well 197 Mixed Estuaries VI-3 Typical Main Channel Salinity and Velocity Profiles for Partially 199 Mixed Estuaries VI-4 Estuarine Dimensional Definition 201 VI-5 Suggested Procedure to Predict Estuarine Water Quality 206 VI-6 Estuarine Circulation-Stratification Diagram 209 VI-7 Examples of Estuarine Classification Plots 209 VI-8 Circulation and Stratification Parameter Diagram 212 VI-9 The Stuart Estuary 214 VI-10 Stuart Estuary Data for Classification Calculations 215 VI-11 Estuarine Circulation-Stratification Diagram 218 VI-12 Alsea Estuary Seasonal Salinity Variations 220 VI-13 Estuary Cross-Section for Tidal Prism Calculations 223 VI-14 Patuxent Estuary Salinity Profile and Segmentation Scheme Used 237 in Flushing Time Calculations VI-15 Hypothetical Two-Branched Estuary 241 VI-16 Cumulative Upstream Water Volume, Fox Mill Run Estuary 246 VI-17 River-Borne Pollutant Concentration for One Tidal Cycle 259 VI-18 Alsea Estuary River-Borne Conservative Pollutant Concentration 263 VI-19 Pollutant Concentration form an Estuarine Outfall 265 VI-20 Hypothetical Concentration of Total Nitrogen in Patuxent Estu- 271 ary vm ------- Figure Page VI-21 Relative Depletions of Three Pollutants Entering the Fox Mill Run 281 Estuary, Virginia VI-22 Additive Effect of Multiple Waste Load Additions 283 VI-23 Dissolved Oxygen Saturation as a Function of Temperature and Sa- 296 linity VI-24 Predicted Dissolved Oxygen Profile in James River 298 VI-25 Definition Sketch for Pritchard's Two-Dimensional Box Model 302 VI-26 Patu ent Estuary Model Segmentation 311 VI-27 Waste Field Generated by Marine Outfall 316 VI-28 Example Output of MERGE - Case 1 326 VI-29 Example Output of MERGE - Case 2 327 VI-30 Schematic of Plume Behavior Predicted by MERGE in the Present 332 Usage VI-31 Cross Diffuser Merging 336 VI-32 Plan View of Spreading Sewage Field 355 VI-33 Outfall Location, Shellfish Harvesting Area, and Environs 360 VI-34 Dissolved Oxygen Depletions Versus Travel Time 366 VI-35 Center!ine Dilution of Round Buoyant Jet in Stagnant Uniform 377 Environment VI-36 Mean Suspended Solids in San Francisco Bay 381 VI-37 Water Quality Profile of Selected Parameters Near a Municipal 386 Outfall in Puget Sound, Washington VI-38 Sediment Movement in San Francisco Bay System 396 VI-39 Idealized Estuarine Sedimentation 397 VI-40 Particle Diameter Versus Settling Fall per Tidal Cycle (12.3 hrs) 402 under Quiescent Conditions (Spheres with Density 2.0 g/cm3) VI-41 Estuarine Null Zone Identification 405 ------- LIST OF TABLES PART 2 Table Page V-l Parameter Values Used in Generation of Thermal Gradient Plots 10 (Appendix D) V-2 Temperature, Cloud Cover, and Dew Point Data for the Ten Geogra- 12 phic Locales Used to Develop Thermal Stratification (Appendix D) V-3 Limpid Lake Characteristics 18 V-4 Physical Characteristics of Lake Smith 20 V-5 Comparison of Monthly Climatologic Data for Shreveport, Louisiana, 21 and Atlanta, Georgia V-6 Hypothetical Physical Characteristics of Upper Lake, Brookhaven, 44 Suffolk County, New York V-7 Hypothetical Physical Characteristics of Lower Lake, Brookhaven, 46 Suffolk County, New York V-8 Hypothetical Physical Characteristics of Lower Lake, Brookhaven, 48 Suffolk County, New York (Assuming an Epilimnion Depth of 10 ft) V-9 Classification of Lake Restoration Techniques 83 V-10 Oxygen Demand of Bottom Deposits 104 V-ll Solubility of Oxygen in Water 106 V-12 Characteristics of Quiet Lake 115 V-13 Water Quality and Flow Data for Tributaries to Quiet Lake. Data 115 Represent Mean Figures for 1970-1975 V-14 Precipitation and Runoff Data for Quiet Watershed. Values Are 118 Means of Data Collected from Both Stations. V-l5 DO Sag Curve for Quiet Lake Hypolimnion 127 V-16 Significant Processes Affecting Toxic Substances in Aquatic 129 Ecosystems ------- Table Page V-17 Comparison of Modeled Thermal Profiles to Observed Temperatures 154 in Occoquan Reservoir V-18 Annual Sediment and Pollutant Loads in Occoquan Watershed 157 V-19 Sediment Loaded into Lake Jackson 158 V-20 Calculation Format for Determining Sediment Accumulation in 159 Reservoirs V-21 Particle Sizes in Penn Silt Load 160 V-22 Calculation Format for Determining Sediment Accumulation in 161 Reservoirs V-23 Sewage Treatment Plant Pollutant Loads in Bull Run Sub-Basin 167 V-24 Calculated Annual Pollutant Loads to Occoquan Reservoir 168 V-25 Observed Annual Pollutant Loads to Occoquan Reservoir 170 V-26 Calculated and Observed Mean Annual Pollutant Concentrarions in 172 Occoquan Reservoir VI-1 Summary of Methodology for Estuarine Water Quality Assessment 205 VI-2 Tidal Prisms for Some U.S. Estuaries 224 VI-3 Sample Calculation Table for Calcu ation of Flushing Time by 234 Segmented Fraction of Freshwater Method VI-4 Patuxent Estuary Segment Characteristics for Flushing Time Calcu- 236 lations VI-5 Flushing Time for Patuxent Estuary 239 VI-6 Sample Calculation Table for Estuarine Flushing Time by the Modi- 245 fied Tidal Prism Method VI-7 Data and Flushing Time Calculations for Fox Mill Run Estuary 249 VI-8 Pollutant Distribution in the Patuxent River 257 VI-9 Incremental Total Nitrogen in Patuxent River (See Problem VI-5) 258 VI-10 Sample Calculation Table for Distribution of a Locally Discharged 267 Conservative Pollutant fy the Fraction of Freshwater Method VI-11 Nitrogen Concentration in Patuxent Estuary Based on Local Dis- 269 charge xi ------- Table Page VI-12 Typical Values for Decay Reaction Rates V 273 VI-13 Sample Calculation Table for Distribution of a Locally Dis- 277 charged Non-conservative Pollutant by the Modified Tidal Prism Method VI-14 Salinity and CBOD Calculations for Fox Mill Run Estuary 279 VI-15 Distribution of Total Nitrogen in the Patuxent Estuary due to 286 Two Sources of Nitrogen VI-16 Tidally Averaged Dispersion Coefficients for Selected Estuaries 289 VI-17 Tidally Averaged Dispersion Coefficients 290 VI-18 Salinity and Pollutant Distribution in Patuxent Estuary under 310 Low Flow Conditions VI-19a Water Densities Calculated using the Density Subroutine Found 320 in MERGE VI-19b Water Densities Calculated using the Density Subroutine Found 321 in MERGE VI-19c Water Densities Calculated using the Density Subroutine Found 322 in MERGE VI-20 Plume Variables, Units, and Similarity Conditions 325 VI-21 Values of Equilibrium Constants and Ion Product of Water as a 343 Function of Temperature for Freshwater and Salt Water VI-22 Estimated pH Values after Initial Dilution 346 VI-23 Dissolved Oxygen Profile in Commencement Bay, Washington 351 VI-24 Subsequent Dilutions for Various Field Widths and Travel Times 358 VI-25 Data Needed for Estuary Thermal Screening 370 VI-26 Maximum Allowable Channel Velocity to Avoid Bed Scour 393 VI-27 Sediment Particle Size Ranges 399 VI-28 Rate of Fall in Water of Spheres of Varying Radii and Constant 400 Density of 2 as Calculated by Stokes1 Law xn ------- CHAPTER 5 IMPOUNDMENTS 5.1 INTRODUCTION This chapter contains several methods for assessing water quality and physical conditions in impoundments. The general topics covered are sediment accumulation, thermal stratification, DO-BOD, euthrophication, and toxicant concentrations. These topics cover the major water problems likely to occur in impoundments. The methods developed are easy to use and require readily obtainable data. Because the methods depend upon a number of simplifying assumptions, estimates should be taken only as a guide pending further analysis. Also, since pollutant inputs are dependent on previous calculations, familiarity with the methods in previous chapters will be very helpful and expand understanding of the various processes. Some of the techniques are more mechanistic and reliable than others. For example, the thermal stratification technique is based upon output of a calibrated and validated hydrothermal model. The model has been shown to be a good one, and to the extent that physical conditions in the studied impoundments resemble those of the model, results should be very reliable. On the other hand, the methods for predicting eutrophication are empirical and based upon correlations between historical water quality conditions and algal productivity in a number of lakes and reservoirs. Because algal blooms are sensitive to environmental factors and the presence of toxicants and factors other than those involved in the estimation methods, the methods for predicting eutrophication will occasionally be inapplicable. Since the planner may not be able to assess applicability in specific cases, results may occasionally be inaccurate. In using the techniques to be presented, it is important to apply good "engineering judgment" particularly where sequential application of methods is likely to result in cumulative errors. Such would be the case, for example, in evaluating impoundment hypolimnion DO problems resulting from algal blooms. If methods presented below are used to evaluate hypolimnion DO, the planner should determine when stratification occurs, the magnitude of point and nonpoint source BOD loads, and algal productivity and settling ------- rates. From all of this, he may then predict BOD and DO levels in the hypolimnion. Since each of these techniques has an error associated with it, the end result of the computation will have a significant error envelope and results must be interpreted accordingly. The best way to use any of the techniques is to assume a range of values for important coefficients in order to obtain a range of results within which the studied impoundment is likely to fall. Although scientists and engineers are familiar with the metric system of units, planners, local interest groups, and the general public are more accustomed to the English system. Most morphometric data on lakes and impoundments are in English units. The conversion tables in Appendix H should be thoroughly familiar before using these techniques and users should be able to perform calculations in either system even though metric units are simpler to use. Also, dimensional analysis techniques using unit conversions are very helpful in performing the calculations. The methods presented below are arranged in an order such that the planner should be able to use each if he has read preceding materials. The order of presentation is: • Impoundment stratification (5.2) § Sediment accumulation (5.3) • Eutrophication (5.4) t Impoundment dissolved oxygen (5.5) • Fate of Priority Pollutants (Toxics)(5.6) It is strongly recommended that all materials presented be read and examples worked prior to applying any of the methods. In this way a better perspective can be obtained on the kinds of problems covered and what can be done using hand calculations. A glossary of terms has been placed after the reference section so that equation terms can easily be checked. The final section (5.7) is an example application to a selected site. This example allows the user to have an integrated view of an actual problem ------- and application. Also "the goodness of fit" to measured results can be evaluated. 5.2 IMPOUNDMENT STRATIFICATION 5.2.1 Discussion The density of water is strongly influenced by temperature and by the concentration of dissolved and suspended matter. Figure V-l shows densities for water as a function of temperature and dissolved solids concentration (from Chen and Orlob, 1973). Regardless of the reason for density differences, water of lowest density tends to move upward and reside on the surface of an impoundment while water of greatest density tends to sink. Inflowing water seeks an impoundment level containing water of the same density. Figure V-2 shows this effect schematically. Where density gradients are very steep, mixing is inhibited. Thus, where the bottom water of an impoundment is significantly more dense than surface water, vertical mixing is likely to be unimportant. The fact that low density water tends to reside atop higher density water and that mixing is inhibited by steep gradients often results in impoundment stratification. Stratification, which is the establishment of distinct layers of different densities, tends to be enhanced by quiescent conditions. Conversely, any phenomenon encouraging mixing, such as wind stress, turbulence due to large inflows, or destabilizing changes in water temperature will tend to reduce or eliminate strata. 5.2.1.1 Annual Cycle in a Thermally Stratified Impoundment Figure V-3 shows schematically the processes of thermal stratification and overturn which occur in many impoundments. Beginning at "a" in the figure (winter), cold water (at about 4°C) flows into the impoundment which may at this point be considered as fully mixed. There is no thermal ------- 1.0090 1.0070 — 1.0050 E o> c ------- STRATIFIED IMPOUNDMENT DENSITY PROFILE Density of Warm Influent Density of Cool Influent Density FIGURE V-2 !IJATER FLOWING INTO AN IMPOUNDMENT TENDS TO MIGRATE TOWARD A REGION OF SIMILAR DENSITY ------- LATE FALL-WINTER FALL OVERTURN - Water Displaced upward 0 i5 10 15 20 25 30 t T(«C) Inflo. Temperoture 0 5 10 15 20 25 : TCC) i SPRING SUMMER STRATIFICATION FIGURE V-3 ANNUAL CYCLE OF THERMAL STRATIFICATION AND OVERTURN IN AN IMPOUNDMENT ------- gradient over depth and the impoundment temperature is about 6 C. During spring ("b"), inflowing water is slightly warmer than that of the impoundment because of the exposure of the tributary stream to warmer air and increasingly intense sunlight. This trend continues during the summer ("c"), with tributary water being much warmer and less dense than the deep waters of the impoundment. At the same time, the surface water of the impoundment is directly heated by insolation. Since the warm water tends to stay on top of the impoundment, thermal strata form. As fall approaches ("d"), day length decreases, air temperatures drop, and solar intensity decreases. The result is cooler inflows and a cooling trend in the surface of the impoundment. The bottom waters lag behind the surface in the rate of temperature change, and ultimately the surface may cool to the temperature of the bottom. Since continued increases in surface water density result in instability, the impoundment water mixes (overturns). 5.2.1.2 Monomictic and Dimictic Impoundments The stratification and overturn processes described in Figure V-3 represent what occurs in a monomictic or single-overturn water body. Some o impoundments, especially those north of 40 N latitude and those at high elevation may undergo two periods of stratification and two overturns. Such impoundments are termed "dimictic." In addition to the summer stratification and resulting fall overturn, such impoundments stratify in o late winter. This occurs because water is most dense near 4 C, and bottom waters may be close to this temperature, while inflowing water is colder and o less dense. As the surface goes below 4 C, strata are established. With o spring warming of the surface to 4 C, wind induced mixing occurs. ------- 5.2.1.3 Importance of Stratification Stratification is likely to be the single most important phenomenon affecting water quality in many impoundments. Where stratification is absent, water mixes vertically, and net horizontal flow is significant to considerable depths. Since the water is mixed vertically, DO replenishment usually occurs even to the bottom and anoxic (literally "no oxygen") conditions are unlikely. Generally speaking, fully mixed impoundments do not have DO deficiency problems. When stratification occurs, the situation is vastly different. Flow within the impoundment is essentially limited to the epilimnion (surface layer). Thus surface velocities are somewhat higher in an impoundment when stratified than when unstratified. Since vertical mixing is inhibited by stratification, reaeration of the hypolimnion (bottom layer) is virtually nonexistent. The thermocline (layer of steep thermal gradient between epilimnion and hypolimnion) is often at considerable depth. Accordingly, the euphotic (literally "good light") zone is likely to be limited to the epilimnion. Thus photosynthetic activity does not serve to reoxygenate the hypolimnion. The water that becomes the hypolimnion has some oxygen demand prior to the establishment of strata. Because bottom (benthic) matter exerts a further demand, and because some settling of particulate matter into the hypolimnion may occur, the DO level in the hypolimnion will gradually decrease over the period of stratification. Anoxic conditions in the hypolimnion result in serious chemical and biological changes. Microbial activity leads to hydrogen sulfide (HzS) evolution as well as formation of other highly toxic substances, and these may be harmful to indigenous biota. It should be noted that the winter and spring strata and overturn are relatively unimportant here since the major concern is anoxic conditions in the hypolimnion in summer. Thus all impoundments will be considered as monomictic. ------- Strong stratification is also important in prediction of sedimentation rates and trap efficiency estimates. These topics are to be covered later. 5.2.2 Prediction of Thermal Stratification Computation of impoundment heat influx is relatively straightforward, but prediction of thermal gradients is complicated by prevailing physical conditions, physical mixing phenomena, and impoundment geometry. Such factors as depth and shape of impoundment bottom, magnitude and configuration of inflows, and degree of shielding from the wind are much more difficult to quantify than insolation, back radiation, and still air evaporation rates. Since the parameters which are difficult to quantify are critical to predicting stratification characteristics, no attempt has been made to develop a simple calculation procedure. Instead, a tested model (Chen and Orlob, 1973; Lorenzen and Fast, 1976) has been subjected to a sensitivity analysis and the results plotted to show thermal profiles over depth and over time for some representative geometries and climatological conditions. The plots are presented in Appendix D. o The plots show the variation in temperature ( C) with depth (meters). Temperature is used as an index of density. Engineering judgment about defining layers is based on the pattern of temperature with depth. If stratification takes place, the plot will show an upper layer of uniform or slightly declining temperature (epilimnion), an intermediate layer of sharply declinging temperature (thermocline), and a bottom layer (hypolimnion). A rule of thumb requires a temperature change of at least 1 C/meter to define the thermocline. However, this can be tempered by the observation of a well defined mixed layer. To assess thermal stratification in an impoundment, it is necessary only to determine which of the sets of plots most closely approximates climatic and hydrologic conditions in the impoundment studied. Parameters which were varied to generate the plots and values used are shown in Table V-l. ------- TABLE V-1 PARAMETER VALUES USED IN GENERATION OF THERMAL GRADIENT PLOTS (APPENDIX D) Parameter Geographic Locale Geometry Depth (maximum, feet) 20 40 75 100 200 Value Atlanta, Georgia Billings, Montana Burlington, Vermont Flagstaff, Arizona Fresno, California Minneapolis, Minnesota Salt Lake City, Utah San Antonio, Texas Washington, D.C. Wichita, Kansas Surface ? 3 Area (feet ) Volume (feet ) 8.28 x 106 7.66 x 107 3.31 x 107 6.13 x 108 1.16 x 108 4.04 x 109 2.07 x 108 9.58 x 109 8.28 x 108 7.66 x 1010 Mean Hydraulic Residence Time Wind Mixing* Days 10 30 75 250 High Low *See Appendix E. 10 ------- Table V-2 shows the climatological conditions used to represent the geographic locales listed in Table V-l. For details of the simulation technique, see Appendix E. 5.2.2.1 Using the Thermal Plots Application of the plots to assess stratification characteristics begins with determining reasonable values for the various parameters listed in Table V-l. For geographic locale, the user should determine whether the impoundment of interest is near one of the ten areas for which thermal plots have been generated. If so, then the set of plots for that area should be used. If the impoundment is not near one of the ten areas, then the user may obtain data for the parameters listed in Table V-2 (climatologic data) and then select the modeled locale which best matches the region of interest. Next, the user must obtain geometric data for the impoundment. Again, if the impoundment of interest is like one for which plots have been generated, then that set should be used. If not, the user should bracket the studied impoundment. As an example, if the studied impoundment is 55 feet deep (maximum), with a surface area of about 4xl07 feet2, then the 40 and 75 foot deep impoundment plots should be used. Mean hydraulic residence time (T , years) may be estimated using the mean total inflow rate (Q, mVyear) and the impoundment volume (V,m3): TW = V/Q (V-l) Again, the sets of plots bracketing the value of T should be examined. Where residence times are greater than 200 days, the residence time has little influence on stratification (as may be verified in Appendix D) and either the 200 day or infinite time plots may be used. Finally, the wind mixing coefficient was used to generate plots for windy areas (high wind) and for very well protected areas (low wind). The 11 ------- TABLE V-2 TEMPERATURE, CLOUD COVER, AND DEW POINT DATA FOR THE TEN GEOGRAPHIC LOCALES USED TO DEVEOP THERMAL STRATIFICATION PLOTS ( APPENDIX D). SEE FOOT OF TABLE FOR NOTES, Temperature (°F) Max. Mean January February March April May June July August September October November December January February March April May June July August September October November December Atlanta 54 57 63 72 81 87 88 88 83 74 62 53 killings 27 32 38 51 60 68 79 78 67 55 38 32 (Lat: 45 47 52 61 70 77 79 78 73 63 51 44 (Lat 18 22 27 38 47 54 63 61 52 42 29 22 Mm. 33.8°N, 36 37 41 50 57 66 69 68 63 52 40 35 :45.8°N, 9 12 16 26 34 40 46 45 37 30 20 14 Dew 0 C" Point (°F) F Long:84.4°W) 34 34 39 48 57 65 68 67 62 51 40 34 Long:108.5°W) 11 16 20 28 38 46 48 46 38 31 22 15 loud Cover Wind raction (MPH) .63 .62 .61 .55 .55 ."58 .63 .57 .53 .45 .51 .62 .68 .68 .71 .70 .64 .60 .40 .42 .54 .56 .66 .66 11 12 12 11 9 8 8 8 8 9 10 10 13 12 12 12 11 11 10 10 10 11 13 13 12 ------- TABLE V-2 - CONT. Temperature ( F) Max. Mean Burlington (Lat:44 January February March April May June July August September October November December January February March April May June July August September October November December 27 29 38 53 67 54 82 80 71 59 44 31 Fl 40 43 50 59 68 77 81 79 75 63 51 44 18 19 29 43 56 66 71 68 60 49 38 23 agstaff (Lat:35 27 30 36 43 51 60 66 64 59 47 36 30 Min. .5°N, 9 10 20 33 44 77 59 57 49 39 29 15 .2°N, 14 17 22 28 34 42 50 49 42 31 21 17 Dew Cloud Cover Wind Point (°F) Fraction (MPH) Lat:73.2°W) 12 12 20 32 43 54 59 58 51 40 30 17 Long:111.3°W) 14 16 17 20 22 25 43 43 35 25 20 15 .72 .69 .66 .67 .67 .61 .58 .57 .60 .65 .79 .78 .59 .49 .50 .49 .41 .24 .54 .53 .29 .31 .34 .44 10 10 10 10 9 9 8 8 8 9 10 10 8 9 11 12 11 11 9 9 8 8 8 7 13 ------- TABLE V-2 CONT. Temperature ( F) Max. Mean Min. Dew Cloud Cover Wind Point (°F) Fraction (MPH) Fresno (Lat:36.7°N, Long:119.8°W) January February March April May June July August September October November December January February March April May June July August September October November December 55 61 68 76 85 92 100 98 92 81 68 57 Minneapol 22 26 37 56 70 79 85 82 72 60 40 27 46 51 55 61 68 75 81 79 74 65 54 47 is (Lat: 12 16 28 45 58 67 76 71 61 48 31 18 37 40 42 46 52 57 63 61 56 49 40 38 45.0°N, 3 5 18 33 46 56 61 59 49 37 21 9 38 41 41 44 45 48 51 52 51 46 42 40 Long:93.3°W) 6 10 20 32 43 55 60 59 50 40 25 13 .67 .61 .53 .44 .34 .19 .11 Ml " .15 .28 .44 .70 .65 .62 .67 .65 .64 .60 .49 .51 .51 .54 .69 .69 6 6 7 7 8 8 7 6 6 5 5 5 11 11 12 13 12 11 9 9 10 11 12 11 14 ------- TABLE V-2 CONT. Temperature ( F) January February March April May June July August September October November December Max. Salt Lake 37 42 51 62 72 82 92 90 80 66 49 40 Mean Min. City (Lat:40. 27 33 40 50 58 67 76 75 65 53 38 23 8°N, 18 23 30 37 45 52 61 59 50 39 28 32 San Antonio (Lat:29.4°N, January February March April May June July August September October November December 62 66 72 79 85 92 94 94 89 82 70 65 52 55 61 68 75 82 84 84 79 71 59 42 42 45 50 58 65 72 74 73 69 60 49 54 Dew Cloud Cover Wind / O v * * Point ( F) Fraction . , Long:111.9°W) 20 23 26 31 36 40 44 45 38 34 28 24 Long:98.5°W) 39 42 45 55 64 68 68 67 65 56 46 41 .69 .70 .65 .61 .54 .42 '.35 .34 .34 ,43 .56 .69 .64 .65 .63 .64 .62 .54 .50 .46 .49 .46 .54 .57 (MPH) 7 8 9 9 10 9 9 10 9 9 8 7 9 10 10 11 10 10 10 8 8 8 9 9 15 ------- TABLE V-2 CONT. Temperature ( Max. Mean Washington, D.C. January February March April May June July August September October November December January February March April May June July August September October November December 44 46 54 60 76 83 87 85 79 68 57 46 Wichita 42 47 56 68 77 88 92 93 84 72 34 45 37 38 45 56 66 74 78 77 70 59 48 43 (Lat:37. 32 36 45 57 66 77 81 81 71 60 55 36 F ) Dew Min. Point ( (Lat:38.9°N, 30 29 36 46 56 65 69 68 61 50 39 31 7°N, Long:97. 22 26 33 45 55 65 69 69 59 48 44 27 Long: 25 25 29 40 52 61 65 64 59 48 36 26 3°W) 21 25 30 41 53 62 65 53 55 43 33 25 Cloud Cover Wind F) Fraction - (MPH) 77.0°W) .61 .56 .56 .54 .54 .51 . .51 .51 .48 .47 .54 .58 .50 .51 .52 .53 .53 .46 .39 .38 .39 .40 .44 .50 11 11 12 11 10 10 9 8 9 9 10 10 12 13 15 15 13 13 12 11 12 12 13 12 16 ------- TABLE V-2 CONT. Notes: Mean: Max.: Min.: Wind: Dew Point: Normal daily average Normal daily maximum Normal daily minimum Mean wind speed, MPH Mean dew point temper temperature, temperature, temperature, •ature, °F. °F. °F. °F. *Complete data were not available for Billings. Tabulated data are actually a synthesis of available data for Billings, Montana and Yellowstone, Wyoming. All data taken from Climatic Atlas of the U.S., 1974. 17 ------- user must judge where his studied impoundment falls and interpolate in the plots accordingly (See Appendix D). EXAMPLE V-l Thermal Stratification Suppose one wants to know the likelihood that hypothetical Limpid Lake is stratified during June. The first step is to compile the physical conditions for the lake in terms of the variables listed in Table V-l. Table V-3 shows how this might be done. Next, refer to the indexes provided in Appendix D to locate the plot set for conditions most similar to those of the studied impoundment. In this case, the Wichita plots for a 200-foot deep impoundment with no inflow and high mixing rate would be chosen (see Table V-3). Figure V-4 is a reproduction of the appropriate page from Appendix D. TABLE V-3 LIMPID LAKE CHARACTERISTICS 1 ten Limpid Lake Available Plot Location Depth, ft (maximum) Volume, ft3 Mean residence time (Tw) i-'i xi na Manhattan, Kansas 180 6xl010 500 days high (windy) Wichita, Kansas 200 7.66 x 1010 -=> (no inflow) high coefficient According to the plots, Limpid Lake is likely to be strongly stratified in June. Distinct strata form in May and overturn probably occurs in December. During June, the epilimnion should extend down to a depth of about eight or ten feet, and the thenr,ocline should extend down to ------- 0 20 zz i: 0 20- 5: 0_ a 40- 0 20- r: :c Q_ LU 040 60 JUL <^ I'D 2'0 3 TEMP. C NQV D 1 10 20 3 TEMP. C 60c 0 20 z: i — Q_ 40 o 60c 0 20 sr = Q_ UJ C3 40 60 0 DTK 10 20 3 TEMP, C PUG (^ 3 I'D 20 3 TEMP. C DEC / 0 20 zr i: Q_ CD 40- 60 0 C 0 20- sr 01 Q_ 40 o 60 nf>i ^ 10 20 3 TEMP, C SEP / D 10 20 : TEMP. C NICHITF 0 20 3: i — Q_ SO 0 C 0 20- sr 01 t— Q_ C3 40 60 0 1 . K JUN ^ 10 20 30 TEMP. C OC1 / Q 10 20 30 TEMP. C RN5R5 200' INITIRL MflXIMUM DEPTH INFINITE HYOR. RES- TIME MflXIMUM MIXING D 10 20 30 TEMP. C FIGURE V-4 THERMAL PROFILE PLOTS "SED IN EXAMPLE V-l 19 ------- about 30 feet. The gradient in the thermocline should be about 1 C per meter. END OF EXAMPLE V-l •EXAMPLE V-2 Thermal Stratification What are the stratification characteristics of Lake Smith? The hypothetical lake is located east of Carthage, Texas, and Table V-4 shows its characteristics along with appropriate values for the thermal plots. TABLE V-4 PHYSICAL CHARACTERISTICS OF LAKE SMITH Item Lake Smith Plot Values Location Depth, ft (maximum) Volume, ft Mean residence time Mixing 15 miles east of Carthage Texas 23 3 x 108 250 days low (low wind) 20 1.66 x 10 8 low mixing coefficient From the available data for Lake Smith, it appears that plots for a 20-foot deep impoundment with no inflow and low mixing coefficient should give a good indication of the degree of summertime stratification. The one remaining problem is climate. Data for nearby Shreveport, Louisiana compare well with those of Atlanta (Table V-5), for v.'hich plots are provided in Appendix D, and latitudes are similar. Shreveport is so.-ewhat warmer and insolation is higher, but this is a relatively uniform difference over the 20 ------- TABLE V-5 COMPARISON OF MONTHLY CLIMATOLOGIC DATA FOR SHREVEPORT, LOUISIANA AND ATLANTA, GEORGIA DATA ARE PRESENTED AS SHREVEPORT/ATLANTA (CLIMATIC ATLAS OF THE U.S., 1974) Temperature, January February March April May June July August September October November December Max. 57/54 60/57 67/63 75/72 83/81 91/87 92/88 94/88 88/83 79/74 66/62 59/53 Mean 48/45 50/47 57/52 65/61 73/70 81/77 82/79 83/78 78/73 67/63 55/51 50/44 °F Min. 38/36 41/37 47/41 55/50 63/57 71/66 72/69 73/68 67/63 55/52 45/40 40/35 Dew Point, °F 38/34 40/34 44/39 54/48 62/57 69/65 71/68 70/67 65/62 55/51 45/40 39/34 Cloud Cover, Fraction .60/".63 .5S/.62 .54/.61 .50/.55 .48/.5S .44/.5S .46/.6S .40/.57 .40/.53 .3S/.45 .46/.51 .5S/.62 Wind, MPH 9/11 9/12 10/12 9/11 9/9 8/8 7/8 7/8 7/8 7/9 8/10 9/10 Shreveport Lat:32.5°N, Long:94°W Atlanta Lat:33.8°N, Long:84.4°W, 21 ------- year. The net effect should be to shift the thermal plots to a slightly higher temperature but to influence the shape of the plots and the timing of stratification little. As a result, the plots for Atlanta may be used, bearing in mind that the temperatures are likely to be biased uniformly low. Figure V-5 (reproduced from Appendix D) shows thermal plots for a 20-foot deep Atlanta area impoundment having no significant inflow and low wind stress. From the figure, it is clear that the lake is likely to stratify from April or May through September, the epilimnion will be very shallow, and the thermocline will extend down to a depth of about 7 feet. The thermal gradient is in the range of about 7 C per meter, as an upper limit, during June. Bottom water warms slowly during the summer until the impoundment becomes fully mixed in October. •END OF EXAMPLE V-2 22 ------- 0 2 • z: x 0. LU CD 6 0 2 • H x Q_ LU 4 • 6c D 2 SI X CL (.1 f a 4 6 nnit 10 20 3 TEMP, C JUL / ) 10 2'0 3 TEMP. C NQV D 10 TEMP 0 2 • ZI x: a_ LU CD D 0 0 2 • SI x: LU C3 0 C 0 2 - sr x: Q_ 4 HP* 10 20 3 TEMP, C DUC / ) I'D 2'0 3 TEMP. C DEC 0 2 • ZI x: Q_ LU a 4 • 6 0 C 0 2 - 2C x: LU C3 4 - o 6 nf 11 / i 10 TEMP, SEP / 20 3 C / 3 10 20 : TEMP. C RTLRNTF 20 ' INF MIN 0 2 zr x: Q_ LU C3 6 0 C 0 2 - 31 X Q_ LU O 4 o 6 1. G JUN / / 10 20 30 TEMP, C OC1 3 10 2'0 30 TEMP. C EDRGIR NITIRL MRXIMUM DEPTH INITE HYDR- RES. TIME IMUM MIXING 20 3D 0 10 20 30 . C TEMP. C FIGURE V-5 THERMAL PROFILE PLOTS APPROPRIATE FOR !'SE IN FXAMPLE v-2 23 ------- 5.3 SEDIMENT ACCUMULATION 5.3.1 Introduction Reservoirs, lakes, and other impoundments are usually more quiescent than tributary streams, and thus act as large settling basins for suspended particulate matter. Sediment deposition in impoundments gradually diminishes water storage capacity to the point where lakes fill in and reservoirs become useless. In some cases, sediment accumulation may reduce the useful life of a reservoir to as little as ten to twenty years (Marsh, et al_., 1975). Just how much suspended matter settles out as water passes through an impoundment, as well as the grain size distribution of matter which remains suspended, is of interest to the planner for several reasons. Suspended sediment within an impoundment may significantly reduce light penetration thus limiting algal and bottom-rooted plant (macrophyte) growth. This, in turn, can adversely affect food availability for indigenous fauna, or may slow plant succession, as part of the natural aging process of lakes. Settling of suspended matter may eliminate harborage on impoundment bottoms thus reducing populations of desirable animal species. More directly, suspended particulates impinging on the gills of fish may cause disease or death. Some minerals, particularly clays, are excellent adsorbents. As a result, farm chemicals and pesticides applied to the land find their way to an impoundment bottom and into its food chain. The sediment which settles is likely to have a substantial component of organic matter which can exert an oxygen demand, and under conditions of thermal stratification, anoxic conditions on the impoundment bottom (in the hypolimnion) can result in generation of toxic gases. Indigenous biota may be harmed or even killed as a result. Knowing the rate of sediment transport and the deposition within an impoundment allows for effective planning to be initiated. If sedimentation rates are unacceptable, then the planner can begin to determine where 24 ------- sediments originate, and how to alleviate the problem. For example, densely planted belts may be established between highly erodible fields and transporting waterways, farming and crop management practices may be changed, or zoning may be modified to prevent a worsening of conditions. These considerations, along with others relating to sediment carriage and deposition in downstream waterways, make estimates of sedimentation rates of interest here. Impoundment sediment computation methods discussed in this section will permit the planner to estimate annual impoundment sediment accumulation as well as short term accumulation (assuming constant hydraulic conditions). Application of the methods will permit the planner to estimate the amount of sediment removed from transport in a river system due to water passage through any number of impoundments. 5.3.2 Annual Sediment Accumulation Three different techniques are used to estimate annual sediment accumulation, available data, sediment rating curves, and a three step procedure to determine short-term sedimentation rates. As discussed under each technique, caution should be used in selecting one method or another. If data are not available, it may not be feasible to use one or more techniques. The uncertainty in the results should be considered in drawing conclusions based on whichever analysis that is selected. 5.3.2.1 Use of Available Data Data provided in Appendix F permit estimation of annual sediment accumulation in acre-feet for a large number of impoundments in the U.S. The data and other materials presented provide some basic impoundment statistics useful to the planner in addition to annual sediment accumulation rates. To use Appendix F, first determine which impoundments within the study area are of interest in terms of annual sediment accumulation. Refer to the U.S. map included in the appendix and find the index numbers of the region 25 ------- within which the impoundment is located. The data tabulation in the appendix, total annual sediment accumulation in acre feet is given by multiplying acerage annual sediment accumulation in acre feet per square mile of net drainage area ("Annual Sediment Accum.") by the net drainage area ("Area") in square miles: Total Accumulation = Annual Sediment Accum. x Area (V-2) To convert to average annual loss of capacity expressed as a percent, divide total annual accumulation by storage capacity (from Appendix F), and multiply by 100. Note that this approach, as well as those presented later, do not account for packing of the sediment under its own weight. This results in an overestimate in loss of capacity. Note also that other data in Appendix F may be of interest in terms of drainage area estimates for determining river sediment loading and assessment of storm water sediment transport on an annual basis. 5.3.2.2 Trap Efficiency and the Ratio of Capacity to Inflow Where data are not available in Appendix F for a specific impoundment, the following method will permit estimation of annual or short-term sediment accumulation rates. The method is only useful, however, for normal ponded reservoirs. To use this approach, a suspended sediment rating curve should be obtained for tributaries to the impoundment. An example of a sediment rating curve is provided in Figure V-6. 26 ------- 10.000 u 100,000 SUSPENDED SEDIMENT DISCHARGE, S: (tons/day) FIGURE V-6 SEDIMENT RATING CURVE SHOWING SUSPENDED SEDIMENT DISCHARGE AS A FUNCTION OF FLOW (AFTER LINSLEY, KOHLER, AND PAULHUS, 1958) 27 ------- On the basis of such a curve, one can estimate the mean sediment mass transport rate (S.) 1n mass per unit time for tributaries. If neither rating curve nor data are available, one may estimate sediment transport rates on a basis of data from nearby channels, compensating for differences by using mean velocities. To a first approximation, it would be expected that: (V-3) where Si = sediment transport rate to be determined in tributary "i" in mass per unit time, • S. = known transport rate for comparable tributary J (j) in same units as S., V- = mean velocity for tributary i over the time period, and V. = mean velocity in tributary j over the same J time period as Vn- Once average transport rates over the time period of interest have been determined, the proportion, and accordingly the weight of sediment settling out in the impoundment may be estimated. Figure V-7 is a graph showing the relationship between percent of sediment trapped in an impoundment versus the ratio of capacity to inflow rate. The implicit relationship is: (V-4) 28 ------- UD Median Curve for Normal Ponded Reservoirs Envelope Curves for Normal Ponded Reservoirs 0.001 0.003 0.007 0.03 0.07 0.2 0.3 0.5 Ratio of Capacity to Inflow 5 7 10 FIGURE V-7 PELATIONSHIP BETWEEN THE PERCENTAGE OF INFLOW-TRANSPORTED SEDIMFNT RETAINED WITHIN AN IMPOUNDMENT AMD PATIO OF TAPACITY TO INFLOW (LlNSLEY, KOHLER, AND PAULHUS, 1958) ------- wh'jre P = percent of inflowing sediment trapped V = capacity of the impoundment in acre-feet, and Q- = water inflow rate in acre-feet per year Data used for development of the curves in Figure V-7 included 41 impoundments of various sizes throughout the U.S. (Linsley, Kohler, and Paulhus, 1958). To estimate the amount of suspended sediment trapped within an impoundment using this method, the capacity of the impoundment in acre-feet must first be determined. Next, average annual inflow, or better, average flow for the time period of interest is estimated. Then, St = S^P (V-5) where S. = weight of sediment trapped per time period t P = trap efficiency (expressed as a decimal) from Figure V-7 A word of caution is in order here. The above described techniques for -evaluating sediment deposition in impoundments are capable of providing reasonable estimates, but only where substantial periods of time are involved - perhaps 6 months or longer. The methods may be used for shorter study periods, but results must then be taken only as very rough estimates, perhaps order-of-magnitude. 5.3.3 Short-Term Sedimentation Rates The three-step procedure presented below provides a means to make short-term sediment accumulation rate estimates for storm-event analysis and to estimate amounts of different grain-size fractions 30 ------- passing through an impoundment. The steps are: • Determine terminal fall velocities for the grain size distribution • Estimate hydraulic residence time • Compute trap (sedimentation) rate 5.3.3.1 Fall Velocity Computation When a particle is released in standing water, it will remain roughly stationary if its density equals that of the water. If the two densities differ, however, the particle will begin to rise or fall relative to the water. It will then tend to accelerate until the drag force imposed by the water exactly counterbalances the force accelerating the particle. Beyond this point, velocity is essentially constant, and the particle has reached terminal velocity. For spheres of specific gravity greater than 1, Stokes1 law expresses the relationship between fall velocity (terminal velocity) and several other physical parameters of water and the particle. where V = terminal velocity of the spherical particle (ft see" ) max _2 g = acceleration due to gravity (32.2 ft sec ) p = mass density of the particle (slugs ft ) _ o p = mass density of water (slugs ft ) w d = particle diameter (ft) _2 u = absolute viscosity of the water (Ib sec-ft ) D = weight density of particle (Ib ft ) 31 ------- DW = weight density of water (Ib ft" ) Stokes1 law is satisfactory for Reynolds numbers between 1x10~4 and 0.5 (Camp, 1968). Reynolds number is given by: D vd * - ~ (V-7) where R = Reynolds number v = particle velocity v = kinematic viscosity of water Generally, for particles of diameter less than 3 x 10 inches (0.7 mm) this criterion is met. For large particles, how far conditions deviate from this may be observed using the following approach (Camp, 1968). According to Newton's law for drag, drag force on a particle is given by: Fd = CAPwv2/2 (V-8) where F . = the drag force C = unitless drag coefficient A = projected area of the particle in the direction of motion Equating the drag force to the gravitational (driving) force for the special case of a spherical particle, velocity is given by: 32 ------- Vmax = 4g (pp - pw)d (V-9) All variables in the expression for V (Equation V-9) may be easily Illu^ estimated except C, since C is dependent upon Reynold's number. Accord- ing to Equation (V-7), Reynolds number is a function of v. Thus a "trial and error" or iterative procedure would ordinarily be necessary to estimate C. However, a somewhat simpler approach is available to evaluate the drag coefficient and Reynolds number. First, estimate O CR using the expression (Camp, 1968): CR2 = 4pw (Pp - pw) gd3/3u2 (V Then, using the plot in Figure V-8, estimate R and then C. For R>0.1 use of Equation (V-9) will give better estimates of V ,v than will max Equation (V-6). Generally, one of the two approaches for spherical particles will give good estimates of particle fall velocity in an effectively laminar flow field (in impoundments). Occasionally, however, it may prove desirable to compensate for nonsphericity of particles. Figure V-9, which shows the effect of particle shape on the drag coefficient C, may be used to do this. Note that for R<1, shape of particle does not materially affect C, and no correction is necessary. A second problem in application of the Newton/Stokes approach described above is that it does not account for what is called hindrance Hindrance occurs when the region of fluid surrounding a falling particle is disrupted (by the particle motion) and the velocity of other nearby particles is thereby decreased. Figure V-10 shows this effect schematically. 33 ------- 10 Values of R = FIGURE V-8 PLOT OF C./R AND rp2 VERSUS R (CAMP, 19B8) 34 ------- Drag Coefficient, C CD c: I '£> > -D ^3 a -H m — ' Tl o -n '•TI o OO Tl T; -2 > -H ~O rn ^-v -,o o en H oo •— ^-^ o o Tl m -< ^y o m :o O - a> »< 3 o _ O ro 1—TT o o> n r O O OJ I I I O O ------- Particles which velocity is affected by vertical velocity field Region of disruption, upward fluid motion Settling sphere Water column containing settling particles FIGURE v-10 SCHEMATIC REPRESENTATION OF HINDERED SETTLING OF PARTICLES IN FLUID COLUMN 36 ------- A very limited amount of research has been done to determine the effect of particle concentration on fall velocity.(Camp, 1968). Some data have been collected however, and Figure V-ll is a plot of a velocity correction factor, v'/Y>as a function of volumetric cancentration. Volumetric concentration is given by: C , = wt w (V-ll) vol p u iu where C , = volumetric concentration vol C . = weight concentration wt 3 As an approximation, the curve for sand may be used to correct v as a function of C ,. EXAMPLE V-3 Settling Velocity Assume that a swiftly moving tributary to a large reservoir receives a heavy loading of sediment which is mostly clay particles. The particles tend to clump somewhat, and average diameters are on the order of 2 microns. The clumps have a specific gravity of 2.2. Applying Stokes1 law for 20°C water, Vmax = lk (PP • Pw} d2 2 V = - — - r x (2. 2x62. 4/32. 2-62. 4/32. 2)x(6.56xlO"6) max (18x2. IxlO'5) = 8.53x1O"6 ft sec"1 = .03 ft hr"1 Thus the particles of clay might be expected to fall about 9 inches per day in the reservoir. It should be noted that for such a low 37 ------- Correction Factor m r~ o o c— > o m o •H o —I o a m •TO m a CO C 3 n> o — O o 3 O CD a -4- o UD CJ1 00 ------- settling rate, turbulence in the water can cause very significant errors. In fact, the estimate is useful only in still waters having a very uniform flow lacking substantial vertical components. END OF EXAMPLE V-3 EXAMPLE V-4 — Settling., Velocity, for a Sand and Clay Suppose a river is transporting a substantial sediment load which is mainly sand and clay. The clay tends to clump to form particles of 10 micron diameter while the sand is of 0.2 mm diameter. The sand particles are very irregular in shape tending toward a somewhat flattened plate form. The specific gravity of the clay is about 1.8 while that of the sand is near 2.8. Given that the water tempera- ture is about 5°C, the terminal velocity of the clay may be estimated as in Example V-3: Vmax = Ts (pp ' pw} v = , - §2^2 - x (0.8x62. 4/32. 2)x(3.28xlO"5) max 18x3.17x10 = 9.4 xlO"5 ft sec"1 = 8 ft day"1 For the sand, apply Equation (V-10) CR2 = 4pw (pp - pw) gd3/3y2 62-4 v 1-8x62.4 3.2.2 x (6.56xlO"4) 32.2 x 32.2 x ; - IF"? - 3x(3. 17x10 V CR2 = 82 39 ------- Referring to Figure V-8, a value of CR2 equal to 82 represents R^2.8 and C*10.3. From Figure V-9, the corrected drag coefficient for discs is close to 10.3 (no correction really necessary). Then, using Equation (V-9) as an approximation, ^ (Pn - Pw) d ii -. ^i 2 w max i 3Cp W V _ 14x32.2x(l.8x62.4/32.2)x6.56xlO"4 max "^3x10.3x62.4/32.7 Vmax = °'07 ft "c"1 = 252 ft hr'1 Thus the clay will settle about 8 feet per day while the sand will settle about 6048 feet per day (252 feet per hour). END OF EXAMPLE V-4 5.3.4 Impoundment Hydraulic Residence Time Once settling velocities have been estimated for selected grain sizes, the final preparatory step in estimating sediment deposi- tion rates is to compute hydraulic residence time. Hydraulic residence time represents the mean time a particle of water resides within an impoundment. It is not, as is sometimes thought, the time required to displace all water in the impoundment with new. In some impoundments, inflowing water may be conceptualized as moving in a vertical plane from inflow to discharge. This is called plug flow. In long, narrow, shallow impoundments with high inflow velocities, this is often a good assumption. As discussed later, however, adoption of this model leads to another problem, namely, is water within the plug.uniform or does sediment concentration vary over depth within the plug? 40 ------- A second model assumes that water flowing into an impoundment instantaneously mixes laterally with the entire receiving layer. The layer may or may not represent the entire impoundment depth. This simpli- fication is often a good one in large surfaced, exposed impoundments having many small inflows. Regardless of the model assumed for the process by which water traverses an impoundment from inflow to discharge, hydraulic residence time is computed as in Equation (V-l). That is, T = V/Q w x The only important qualification is that to be meaningful, V must be computed taking account of stagnant areas, whether these are regions of the impoundment isolated from the main flow by a sand spit or" promontory, or whether they are isolated by a density gradient, as in the thermo- cline and hypolimnion. Ignoring stagnant areas may result in a very substantial overestimate of T , and in sediment trap computations, an overestimate in trap efficiency. Actually T computed in this way is an adjusted hydraulic residence time. All references to hydraulic residence time in the remainder of Section 5.3 refer to adjusted T . Hydraulic residence time is directly influenced by such physical variables as impoundment depth, shape, side slope, and shoaling, as well as hydraulic characteristics such as degree of mixing, stratifi- cation, and flow velocity distributions. The concepts involved in evaluating many of these factors are elementary. The evaluation itself is complicated, however, by irregularities in impoundment shape and data inadequacies. Commonly, an impoundment cannot be represented well by a simple 3-dimensional figure, and shoaling and other factors may restrict flow to a laterally narrow swath through the water body. ------- In most cases, hydraulic residence time may be estimated, although it is clear that certain circumstances tend to make the computation error-prone. The first step in the estimation process is to obtain impoundment inflow, discharge, and thermal regime data as well as topographic/bathymetric maps of the system. Since a number of configu- ration types are possible, the methods are perhaps best explained using examples. EXAMPLE V-5 Hydraulic Residence Time in Unstratified Impoundments The first step in estimating hydraulic residence time for purposes of sedimentation analysis is to determine whether there are signifi- cant stagnant areas. These would include not only regions cut off from the main flow through the body, but also layers isolated by dense strata. Consequently, it must be determined whether or not the im- poundment stratifies. Consider Upper Lake located on the Carmans River, Long Island,, New York. The lake and surrounding region are shown in Figure V-12, and hypothetical geometry data are presented in Table V-6. Based upon Upper Lake's shallowness, its long, narrow geometry, and high tributary inflows, it is safe to assume that Upper Lake is normally unstratified. Also, because of turbulence likely at the high flows, one can assume that the small sac northeast of the discharge is not stagnant and that Upper Lake represents a slow movinq river reach. With these assumptions, the computation of hydraulic residence time is as shown in Table V-6. 42 ------- FIGURE V-12 UPPER AND LOWER LAKES AND ENVIRONS, LONG ISLAND, NEW YORK 43 ------- TABLE V-6 HYPOTHETICAL PHYSICAL CHARACTERISTICS OF UPPER LAKE, BROOKHAVEN, SUFFOLK COUNTY, NEW YORK Distance from Miles 0.05 0. 10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 Downstream Inflow (feet) (264) (528) (792) (1,056) (1,320) (1,534) (1,848) (2,112) (2,376) (2,640) D Average Depth ft. 3 4 6 7 7 8 7 8 7 10 W Average Width ft. 63 no 236 315 340 315 550 550 354 350 CSA Cross-secti Area,_D x ft2 189 440 1,416 2,205 2,380 2,520 • 3,850 4,400 2,478 3,500 onal W Total length = 0.5 mi. (2,640 ft.) Inflow from upstream = 380 cfs Outflow to downstream = 380 cfs (steady-state) mean CSA = 2,338 ft' Computation Volume (Vol) = Total length x mean cross-sectional area Vol = 2,640 ft. x 2,338 ft2 = 6.17 x 106 ft3 Residence time (T ) = Vol/flow W -r = 6.17 x 105 ft3/(380 ft3/sec) = 1.62 x 104 sec (4.5 hr) w Velocity (Vel) = length/-^ Vel = 2,640 ft/1.62 x 104 sec = .163 ft/sec 44 ------- Also shown in Figure V-12 is Lower Lake. According to the hypothetical data presented in Table V-7, Lower Lake is much deeper than Upper Lake. Its volume is significantly greater also, but the inflow rate is similar. In this case, particularly during the summer, it should be determined if the lake stratifies. For this example, however, we will assume that the time of the year makes stratification very un- likely, and that Lower Lake is a slow moving river reach. We then compute hydraulic residence time as shown in Table V-7. Figure V-13 in particular diagram 1, shows what these assumptions mean in terms of a flow pattern for both lakes. END OF EXAMPLE V-5 EXAMPLE V-6 Assume for this example that Lower Lake is stratified during the period of interest. This significantly changes the computation of res- idence time. To a first approximation, one can merely revise the effective depth of the impoundment to be from the surface to the upper limit of the thermocline rather than to the bottom. Figure V-13 shows schematically what this simple model suggests for Lower Lake as a stratified impoundment (diagram 2 or possibly 3). The figure also shows wind-driven shallow, and deep impoundments. To the right of each diagram is a plot of the temperature profile over depth. Actually, the profile could represent a salinity gradient as well as a thermal gradient. Table V-8 shows the procedure to estimate travel time for strati- fied Lower Lake. The upper boundary of the thermocline is assumed to be at a depth of 10 feet. For all later computations of sediment accumulation, this same 10 foot depth would be adopted. Such an assump- tion is valid presuming that the thermocline and hypo!imnion are relatively quiescent. Thus once a particle enters the thermocline it can only settle, and can not leave the impoundment. END OF EXAMPLE V-6 45 ------- TABLE V-7 HYPOTHETICAL PHYSICAL CHARACTERISTICS OF LOWER LAKE, BROOKHAVEN, SUFFOLK COUNTY, NEW YORK Distance Downstream from Inflow Miles (feet) 0.075 ( 396) 0.150 ( 792) 0.225 (1,188) 0.300 (1,584) 0.375 (1,980) 0.450 (2,376) 0.525 (2,772) 0.600 (3,163) 0.675 (3,564) 0.750 (3,960) 0.825 (4,356) 0.900 (4,752) 0.975 (5,148) 1.050 (5,544) 1.125 (5,940) Total length = 1 .125 Inflow from upstream D Average Depth ft. 15 20 20 25 35 30 35 35 40 42 41 51 42 40 37 mi (5,940 ft. 400 cfs ) > ( Outflow to downstream 390 cfs I W Average Width ft. 157 165 173 197 197 228 232 197 220 315 433 591 551 433 323 ) surface rising) j / CSA Cross-sectional Area,0D x W ft2 2,355 3,300 3,460 4,925 6,895 6,840 8,120 6,895 8,800 13,230 17,753 30,141 23,142 17,320 11,951 mean CSA = 11 ,008 Average flow = 395 cfs Computation Volume (Vol ) - Total length x mean cross-sectional area Vol - 5,940 ft. x 11,008 ft2 = 6.54 x 107 ft3 Residence Time (T ) = Vol/flow TW = 6.54 x 107/(395 ft3/sec) = 1.65 x 105 sec (46 hr) Velocity (Vel) = length/Tw Vel = 5,940 ft/1.65 x 105 sec = .036 ft/sec 46 ------- I.AIM>C tuttrAcro, >»»i- MOWN* IMPOUW>«1 NT ICIWWI _j _ "* *"•""'•''•* ^SSfffffifff: $«<<•>«»' i "i" :v:v.v'.v.:x:x:'''' 'V-HWW^vAVAVAv.v.v.vX-H'X*.* • • Thermoclme (EtlcAtiolly Stagnonr) L*R6E SU»F*CfO, UOOERATEtr SHALLOW j iMPOUNOMtNT, VERY LOW VELOCITIES Hypoltmnion l d*tr««H\ i Millrtf i Itt 4«pth with I ) dtcr*o*«4 t-I'X':v.'.vv.v.v.v.v.v.vX-X: ' 1C ...I1)1 1 d«cr*a*«tf mtxiMi -S (3) i ""«« «'« SHALLOW, WIND MIXED (TURBULENT) IMPOUNDMENT S«4lm«ni Laye Ort(", SUPERFICIALLY TURBULENT STRATIFIED IMPOUNDMENT Rtcfiving CMnntl °l FIGURE V-13 IMPOUNDMENT CONFIGURATIONS AFFECTING SEDIMENTATI ON 47 ------- TABLE V-8 HYPOTHETICAL PHYSICAL CHARACTERISTICS OF LOWER LAKE, BROOKHAVEN, SUFFOLK COUNTY, NEW YORK (ASSUMING AN EPILIMNION DEPTH OF 10 FEET) Distance Downstream from Inflow Miles (feet) 0.075 0.150 0.225 0.300 0.375 0.450 0.525 0.600 0.675 0.750 0.825 0.900 0.975 1.050 1.125 D Average Depth ft. 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 W Average Width ft. 160 170 175 200 198 230 233 200 222 316 435 590 552 435 325 CSA Cross-sectional Area , 0D x W ft2 1,600 1 ,700 1,750 2,000 1,980 2,300 2,330 2,000 2,220 3,160 ' • 4,350 - 5,900 5,520 4,350 3,250 Total length = 1.125 mi (5,940 ft.) Inflow from upstream 397 cfs Outflow to downstream 393 cfs Average flow - 395 cfs mean CSA = 2,961 ft' (steady-state surface, difference due to loss to water table) Computation Volume (Vol) = Total length x mean cross-sectional area Vol = 5,940 ft. x 2,961 ft2 = 1.76 x 107 Residence Time (T ) = Vol/flow TW = 1.76 x 107/(395 ft3/sec) = 4.46 x 104 sec (12.3 hr) Velocity (Vel) = length/T w Vel = 5,940 ft/4.46 x 10^ sec = 0.133 ft/sec 48 ------- EXAMPLE V-7 Large, Irregular Surface Impoundment Figure V-14 shows Kellis Pond and surrounding topography. This- small pond is located near Bridgehampton, New York and has a surface area of about 36 acres. From the surface shape of the pond, it is clear that it cannot be considered as a stream reach. Figure V-15 shows a set of hypothetical depth profiles for the pond. From the profiles, it is evident that considerable shoaling has resulted in the formation of a relatively well defined flow channel through the pond. Peripheral stagnant areas have also formed. Hypothetical velocity vectors for the pond are presented in Figure V-16. Based upon them, it is reasonable to consider the pond as being essentially the hatched area in Figure V-15. To estimate travel times, the hatched area may be handled in the same way as for the Upper Lake example presented above. It should be noted, however, that this approach will almost certainly result in underestimation of sediment'deposition in later computations. This is true for two reasons. First, estimated travel time will be smaller than the true value since impoundment volume is underestimated. Second, since the approach ignores the low flow velocities to either side of the central channel and nonuniform velocities within it, heavier sedimentation than computed is likely. 49 ------- SOUTHAMPTON BRIDGEHAMPTON KELLIS POND WEST MECOX VILLAGE MILES FIGURE V-14 KELLIS POND AND SURROUNDING REGION, LONG ISLAND, NEW YORK 50 ------- FIGURE V-15 HYPOTHETICAL DEPTH PROFILES FOR KELLIS POND 51 ------- •STAGNANT STAGNANT- FIGURE V-16 HYPOTHETICAL FLOW PATTERN IN KELLIS POND Still more difficult to evaluate is the situation where shoaling and scour have not resulted in formation of a distinct central channel. Figure V-17 shows hypothetical depth profiles for Kellis Pond for such a case. Here, velocity distribution data should be obtained, particu- 0 larly if the impoundment is of much importance. If such data are not available but it is deemed worthwhile to do field studies, methods available for evaluating flow patterns include dye tracing and drogue floats. A simple but adequate method (at least to evalu- ate the surface velocity distribution) is to pour a large number of citrus fruits (oranges, grapefruit) which float just below the surface, into the impoundment, and to monitor both their paths and velocities. Although it is true that surface velocities may be greater than the velocity averaged over depth, this will permit estimation of hydraulic residence time directly or generation of data to use in the prescribed method. In the latter case, the data might be used to define the major flow path through an impoundment of a form like Kellis Pond. END OF EXAMPLE V-7 EXAMPLE V-8 Comb!ex Geometries The final hydraulic residence time example shows the degree of complexity that sediment deposition problems may entail. Although it is possible to make rough estimates of sediment accumulation, it 52 ------- PLAN VIEW Ns, V TRANSECTS A B D FIGURE V-17 HYPOTHETICAL DEPTH PROFILES FOR KELLIS POND NOT SHOWING SIGNIFICANT SHOALING 53 ------- is recommended that for such impoundments more rigorous methods be used - mathematical modeling and/or detailed field investigations. Figure V-18 shows Lake Owyhee in eastern Oregon. This impound- ment is well outside the ranpo of complexity of rr.ter bodies which can be evaluated using these calculation methods. Because of geometry, the number of tributaries, and size, it isn't feasible to conceptually reduce the impoundment in such a way as to estimate travel times. Flow patterns are likely to be very complex, and sediment deposition is dif- ficult to predict both in terms of quantity and location. In contrast, Figure V-19 shows New Millpond near Islip, New York and surrounding features. Although this water body does not have a simple surface geometry, it can be reduced to three relatively simple components as shown in the figure. Bearing in mind the limita- tions imposed by wind mixing, stratification, and the presence of stagnant regions described in earlier examples, deposition might nevertheless be estimated in arms A, B, and C. Because of the diffi- culty of predicting velocities and turbulence in section D, estimates of sedimentation cannot be reliably made there. However, it is likely that much of inflowing sediments will have settled out by the time water flows through the arms and into section D. END OF EXAMPLE V-8 5.3.5 Estimation of Sediment Accumulation Estimation of quantities of sediment retained in an impoundment follows directly from the computations of settling velocity and travel time, although the computation depends upon whether the adopted model is plug flow, or a fully mixed layer or impoundment. In the case of plug flow, one of two subordinate assumptions is made: that the plug is fully mixed as in turbulent flow, or that 1t moves in a "laminar" flow through the impoundment. In terms of sediment accumulation estimates, the fully mixed plug assumption is 54 ------- LAKE OWYHEE SCALED 12345 FIGURE V-1% IAKE OWYHEE AND ENVIRONS 55 ------- NEWMILLPOND FIGURE V-19 NEW MILLPOND AND FNVIRONS, HEW MILLPOND is SUBDIVIDED FOR PURPOSES OF FSTIMATING SFDI- MENTATION IN REGIONS A, B, AND P., 56 ------- handled in the same way as the fully mixed impoundment model. Thus we have two kinds of computations: Cases^ A • Plug flow with the plug not mixed vertically versus t Plug flow assuming a vertically mixed plug, or • A fully mixed impoundment or stratum Equation (V-12) is pertinent to both cases A and B. It defines the mass of sediment trapped as a function of trap efficiency and inflowing sediment mass. Equation (V-13) should be used for case A, and Equation (V-14) for case B. St = SjP (V-12) P = ((TWV) + D" -Dj/D" (V-13) P »^w D1 (V-14) where P = mean proportion of S. trapped$t = mass of sediment trapped per unit time S. = mass of sediment in inflows per unit time v = particle settling velocity 0 = discharge channel depth D1 = flowing layer depth D" = inflow channel depth 57 ------- Figure V-20 shows the significance of the various depth measures D, D1, and D" , and the assumed sedimentation pattern. In case B, in the absence cf substantial erratic turbulence and unpredicted vertical velocity components, and within the constraints of available data, it is clear that this approach can give reasonable estimates of trap efficiencies. In case A, however, small changes in D or D" can strongly affect trap efficiencies. It is important to remember in applying case A that P is a mean, preferably used over a period of time. It is also important to recognize that conditions within an impoundment leading to selection of case A or B are subject to change, thus affecting estimates. For convenience, Figure V-21 is included to provide estimates °f Vm3 f°r spherical particles of 2.7 specific gravity. The data max are presented as a function of particle diameter and temperature. Figure V-22 is a nomograph relating trap efficiency, P (in percent) to depth D1, V , , and T . The nomograph is useful only for case B (TtG X W assumptions. EXAMPLE V-9 Sedimentation in Upper and Lower Lakes Using the data from Table V-6 and settling velocities for the clay and sand of Example V-4, for case A, 4 T = 1.6x10 sec w Vmax for clay = 8 ft day"1 Vmav for sand = 252 ft hour" max 58 ------- PLUG FLOW, PLUG NOT MIXED VERTICALLY Thermocl ine Hypolimnion Sediment Layer ;.; IMPOUNDMENT - D J_ CASE A Flow PLUG FLOW, VERTICALLY MIXED PLUG D" : .: ••• -::: t \ v.v.^ '••:• c 1 )' IvX'XvX'X'Sediment Layer >XvX'X->X* DOUNDME /:•:•: >%'t"."."." '•'•' •' : .'.':'".\ D S^. " T CASE B Flow FULLY MIXED IMPOUNDMENT OR STRATUM ;Sediment Layer vX-X IMPOUNDMENT — CASE B FIGURE 20 SIGNIFICANCE OF DEPTH MEASURES D, D , AND D , AND THE ASSUMED SEDIMENTATION PATTERN 59 ------- 0 10 15 20 25 30 35 -2-- -3-- u '•£ -4 k_ o Q. 0) -6 - o» o -8 - — -9 .001 mm .00075 mm .0005 mm 00025 mm I x 10 mm FIGURE V-21 SETTLING VELOCITY FOR SPHERICAL PARTICLES 60 ------- 10 -7. IQ-0-- 10 -s:: 10 -4 IO"3-- 10 -2J1 10°-- Tu) io5- --10 10' 10 St/Sj 10 -6 10 -4 IO°-3=l.99°/< \ \ \ \ \ \ \ \ \ X V : Settling velocity in feet/ second T : Hydraulic residence time in seconds D': Flowing layer depth S.: Mass of sediment trapped S.: Mass of sediment entering 1 impoundment L : Pivot axis 10 D' 4- I03" IQ2-- 10'-- 10° |0I.699=50 FIGURE V-22 NOMOGRAPH FOR ESTIMATING SEDIMENT TRAP EFFICIENCY 61 ------- Although it is not specified in Table 7-6, the inflow channel depth at the entrance to Upper Lake is 3 feet. The discharge channel depth is 10 feet. Assuming "laminar" flow with minimal vertical components, for clay: [(Tw x v) + D" - D] TW " DTi P = [(1.6xl04x9.3xlO"5) +3-10] P = -5.5 The negative value implies that the proportion settling out is virtually zero. Thus the clay will to a large extent pass through Upper Lake. However, x for this examole is very small (4.5 hours) w Many impoundments will have substantially larger values. For the sand, p [(1.6x104x7xlO"2) +3-10] 3 P = 371 All of the sand will clearly be retained. Note that a clay or very 4 1 fine silt of vmax = 5x10 ft sec would be only partially trapped. p [Q.6x1Q4x5x10"4) +3-10] 3 P = 0.33 62 ------- Thus about one-third of this sediment loading would be retained. Note that if D is large, trap efficiency drops using this algorithm. For the silt, a discharge channel depth (at the outflow from Upper Lake) of 11 feet rather than 10 would give [Q.6xlQ4x5xlO"4) + 3-11] n - 3 u Thus with D=ll, all silt exits the impoundment. If D is only 9 feet, then p = [Q.6x104x5xlQ"4) +3-9] = o Two-thirds of the silt is retained. Remember that P represents a mean value. Clearly during some periods none of the silt will be retained (due to turbulence, higher velocities) while during other periods, all of the silt will be trapped. The key here is the word "mean." If the impoundment is assumed to be vertically mixed (case B), compute the mean depth D n D = z D./n where n = the number of cross-sections Di = depth at the ith cross-section For Upper Lake, D = 6.7 = D1 63 ------- Then V T P- D' For the clay, 9.3x10"5x1.6x104 About one-fourth of the clay is retained. For the sand, „ 7x10"2xl.6x104 p = _ All of the sand will be trapped within about 1/167 times the length of the lake. If the daily influent loading of sand is one ton, while the loading of clay is fifteen tons, then the daily accumulation will be one ton of sand and 0.22 x 15 = 3.3 tons of clay. Finally, as an example of use of Figures V-21 and V-22, assume that the sediment loading consists primarily of silt particles in the size range of .002mm diameter, and that the water temperature is 5°C. Further, assume T has been estimated as 2.77 days (10 seconds), and that D'=50 feet. From Figure V-21, the settling velocity is about -4 1x10 feet per second. -4 d In Figure V-22, draw a line from 10 on the V axis to 10 on the T axis. The point of intersection with axis L.is L'. Next, compute Iog1050=1.699. Draw a line from this point on the D' axis to !_' . Where this line crosses the S./S. (%) axis gives the log of the percent of the sediment trapped. This is 10 '=1.99=2%. END OF EXAMPLE V-9 64 ------- 5.4 EUTROPHICATION AND CONTROL 5.4.1 Introduction The presence of nutrients in an impoundment generally favors plant growth. Depending upon antecedent conditions, the relative abundance of nitrogen, phosphorus, light, and heat, and the status of a number of other physical and chemical variables, the predominant forms may be diatoms, other microscopic or macroscopic algae, or bottom-rooted or free-floating macrophytes. The quantity of plant matter present in an impoundment is important for several reasons. First, plant cells produce oxygen during photosynthesis, thereby providing an important source of dissolved oxygen to the water column. During the sunlight hours plant cells also consume oxygen through the process of respiration. Respiration occurs along with photosynthesis during the day, but also occurs at night. Oxygen consumed at night may be considerable, not only because it serves to sustain the plant cells, but because the cells actively perform various vital metabolic functions in the dark. Plant growth within an impoundment is also important because plant biomass is a major source of nutrition for indigenous fauna, and the growth of plants constitutes what is called "primary production." The stored energy and nutrients provide food for various grazers higher in the food chain, either through direct consumption of living plant tissue by fishes and zooplankton or through consumption of detritus by fishes, microorganisms, and zooplankton. The grazers, in turn, provide food for predatory fishes, mammals, insects, and other higher forms. Finally, plant development in impoundments is important because it tends to accelerate impoundment aging. As plants grow, organic matter and sediment accumulate. As the impoundment fills with rock fragments, soil, and plant detritus, an excellent substrate forms upon which more suspended matter may be trapped and which may ultimately support the growth of higher plants and trees. The gradual filling in of an impoundment in this way reduces its usefulness, and may finally eliminate the impoundment completely. 65 ------- 5.4.2 Nutrients, Eutrophy, and Algal Growth Eutrophy means literally a state of good nutrition. Plants require a number of nutrients, but to vastly different degrees. Some nutrients, such as carbon, nitrogen, potassium, and phosphorus, are needed in large quantity. These are termed macronutrients. The micronutrients, e.g. iron, cobalt, manganese, zinc, and copper, are needed in very small amounts. In nature, the micronutrients, carbon, and potassium are usually in adequate supply (although not always), while nitrogen and phosphorus are commonly growth limiting. Nitrogen, particularly as nitrate and ammonium ions, is available to water-borne plant cells to be used in synthesis of proteins, chlorophyll _a, and plant hormones. Each of these substances is vital for plant survival. Phosphorus, an element found in a number of metabolic cofactors, is also necessary for plant nutrition. The biosynthesis and functioning of various biochemical cofactors rely on the availability of phosphorus, and these cofactors lie at the very foundation of plant cell metabolism. Without adequate phosphorus, plant cells cannot grow. Since nitrogen and phosphorus are commonly in limited supply, many impoundments tend inherently to be clear and essentially free of clogging algae and vascular plants. Because of society's ever-increasing size and need for food, chemical sources of nitrogen and phosphorus are synthesized and spread over vast tracts of farmland. Stormwater washes off these nutrients, which then flow through streams and into natural and artificial impoundments. Also, excessive nutrients occur in wastewaters from municipalities and industry. Due to the fact that many impoundments have very low flow velocities, impoundments represent excellent bioloaical culturinq vessels, and often become choked with plant life when nutrients increase. Since a plant cell has at any point in time a specific need for nitrogen and for phosphorus, one or the other or both may limit cell growth or replication. Where nitrogen is the nutrient that restricts the rate of plant growth, that is, where all other nutrients and factors are present in 66 ------- excess, we say that nitroqen is growth limiting. In general, N:P ratios in the range of 5 to 10 by mass are usually associated with plant growth being neither nitroaen nor phosphorus limited. However, in this range, plant growth may well be limited by N and P collectively. Where the ratio is greater than 10, phosphorus tends to be 1'miting, and for ratios below 5, nitrogen tends to be limiting (Chiaudani, _et _al_., 1974). In addition to nitroqen and phosphorus, any necessary nutrient or physical condition may limit plant growth. For example, in highly nutritious (eutrophic) waters, algal biomass may increase until light cannot penetrate, and light is then limiting. At such a point, a dynamic equilibrium exists in which algal cells are consumed, settle or lyse (break) at the same rate as new cells are produced. To summarize, the process of eutrophication (or fertilization) is enrichment of a lake with nutrients, particularly nitrogen and phosphorus. However, the problem of eutrophication resulting from increased plant biomass caused by enrichment will be discussed. Some of the problems of predicting algae and the screening method will be developed for screening purposes, a nutrient approach will be taken so that control measures can be evaluated and then, plant biomass (algal blooms and macrophytes), will be estimated to provide a relationship with the problem of eutrophication. 5.4.3 Predicting Algal Concentrations Predicting algal blooms or predominance of macrophytes using a mechanistic approach can be a very complex problem, and most methods are not suited to a simple hand calculation technique. Some relationships regarding algal productivity have been derived, however, which permit an evaluation of the eutrophic state of an impoundment. Because the methods permit algal biomass to be estimated with relatively little, easily obtained data, and because algae are very important in assessing impoundment water quality, these techniques are useful here. The methods presented below are based upon the fact that in most cases (perhaps 60 percent) phosphorus is the biomass limiting nutrient (EPA, 1975). One such approach has been developed by Vollenweider (Vollenweider, 1976; Lorenzen, 1976). It may be used to 67 ------- predict the degree of impoundment eutrophication as a function of areal phosphorus loading. It does not, however, permit direct estimates of algal biomass to be made. Before considering application of any of the methods to assess eutrophication, it is important to examine the nitrogen to phosphorus ratio. This indicates whether any of the methods presented below is "likely to give realistic results. ( ',^N 5.4.3.1 Nutrient Limitation .^xt .^ -• ^ )L^ /$*X '" {>C|0'> Generally, an average algal cell has an elemental composition for the macronutrients of Cioe Nie Pi. With 16 atoms of nitrogen for each atom of phosphorus, the average composition bv weight is 6.3 percent nitrogen and 0.87 percent phosphorus or an N/P ratio of 7.2/1. For N/P ratios greater than 7.?, phosphorus would be less available for growth ("limiting") and less than 7.2, nitrogen would be limiting. In practice, values of less than 5 are considered nitrogen limiting, greater than 10 are phosphorus limitinq, and between 5 and 10, both are limiting. In many cases of eutrophic lakes, nitrogen is not limiting because of the process of nitrogen fixation. Some blue-green algae, a particularly noxious type of algae, have enzymatic processes for the biochemical conversion of dissolved elemental nitrogen into reduced nitrogen (amine groups) suitable for growth and metabolism. Special cells called heterocysts perform this process and only appear when nitrogen is limiting. It can be argued that in general nitrogen is not limiting and a "worst case" analysis can be made for a screening approach using phosphorus. However, the chlorophyll produced is affected by the N/P ratio as are the algal species. 68 ------- 5.4.3.2 Nutrient Availability Availability of nutrients is also important. Participate nitrogen and phosphorus in the inflowing tributaries generally settle and can therefore be considered unavailable. Few estimates of bioavailable nutrients have been made and only for phosphorus. Cowen and Lee (1976) indicated that 30 percent or less of urban runoff phosphorus was available to algae while Dorich et aj_. (1980) found a value of 20 to 30 percent for sediment bound phosphorus (as would occur in rural runoff). It appears that a fraction of 0.3 would provide a conservative estimate of bioavailable phosphorus in the absence of actual measurements. 5.4.4 Mass Balance of Phosphorus A material entering a lake or impoundment will partition between the aqueous and solid phases. The solid phase can settle and become bottom sediment or outflow can remove suspended and aqueous phase material. A diagramatic presentation of this concept is shown in Figure V-23. The concentration of the material can be calculated very simply after making several assumptions: the lake is completely mixed, the lake is at steady state and inflowing water equals outflow, and the annual average rates are constant. Although these assumptions are not met entirely for phosphorus, they are satisfied well enough to meet requirements for a screening analysis of eutrophication. Based on its historical development the eutrophication screening methods are termed the "Vollenweider Relationship." As shown in Figure V-23, any of three different forms of the steady state equation can be used to predict phosphorus concentrations in lakes. Each form may be more or less suitable for a specific data set. The important variables are the hydraulic flushing or dilution rate (Q/V, inverse of residence time), lake volume to area ratio (V/A, equals mean depth), phosphorus in the influent (PI), and the net rate of removal (K). The variables Q, V, A must be determined from other data. The influent phosphorus can be based on measurements or estimated from calculations performed as in Chapter 3 and including any municipal and industrial 69 ------- QI = INFLOW XI CONCENTRATION OF POLLUTANT A = AREA WATER Y OUTFLOW = Q SEDIMENTS V = VOLUME X = CONCENTRATION IN LAKE For Example - Phosphorus, P = X LOADING Lp = QI • PI / A, mg/m2 year MASS BALANCE Assumptions Definitions completely mixed, steady state, Q = QI , annual average rates are constant Mean depth, Z = V/A; hydraulic flushing or dilution rate, D = Q/V; hydraulic loading, q = Q/A; M = QI • PI; K = net rate of solid phase removal and release (proportional to P), typically negative when averaged over the annual cycle. . KP , Solving for P, D • PI P = P = D + K M / 1D + K p = __ (Mass Balance Form) (Mass Inflow Form) (Loading Form) FIGURE V-23 FORMULATIONS FOR EVALUATING MANAGEMENT OPTIONS FOR POLLUTANTS IN LAKES AND RESERVOIRS 70 ------- effluents. Generally, effluents are considered totally available for growth. Nonpoint sources should be assessed as 100 percent available and as 30 percent available to provide limits for screening purposes. Estimation of the net rate of removal (K) is not as clear. Jones & Bachmann (1976) estimated that K=0.65 by least squares fitting of data for 143 lakes. Vollenweider (1976) and Larsen and Mercier (1976) independently estimated the net rate of removal as a function of dilution rate: This approach is best used for screening. Also the value of K can be estimated from the ratio (R) of the measured mass phosphorus retained (in-out) and the mass inflow: QI-PI - Q.-_P. = PI-JL " ._. QI-PI " PI P-Z To assess the placement of a specific lake relative to a set of lakes, phosphorus loading (PL) is graphed as a function of hydraulic loading (q ) (Figure V-24). The data for 34 U.S. surface waters are shown. (Some lakes occur more than once because of multi-year studies.) -EXAMPLE V-10 Big Reservoir and The Voilen wej_c!er _Re_l_at,ionship To use the Vollenweider relationship for phosphorus loading, data on long-term phosphorus loading rates must be available. It is also important that the rates represent average loading conditions over time because transient phosphorus loading pulses will give misleading results. Big Reservoir is a squarish reservoir end has the follc.-.ing characteristics: 71 ------- fj 001 ™TT; .6 JJ 10 i 1 i—i : ; ; 11; ——i 1—i—i—TTTT] ;r 35 O « 29 16 128 / EUTROPHIC • * /EXCESSIVE ? 8 4 / / «n* o' °5° ° / /PERMISSIBLE ^ |- °14 «46 X X 47 22 «3' 30 49 / / II ° °2 • • / / 9 54 X / O C 3 13® 39«» *!,, / ^X 25 43 7 «" ./ *5I X « «44 -^ ^ INVESTIGATOR-INDICATED - O "" — ~~ ' TROPHIC STATE : ^ , 53 23-B ^^ O -EUTROPHIC o: "" o o CL to O X a. 24-A _9-*^ A-MESOTROPHIC O24-B O -OLIGOTROPHIC 012 o 35 I9 002I '0 OLIGOTROPHIC o \ I _, I 1 I I I M) I I I I _1 ,1 I l! I ' 1 I I Mil 1 . I .. .' 1 . 1 .M I Ol I 10 100 1000 MEAN DEPTH Z/HYDRAULIC RESIDENCE TIME . T^ ( m /yr ) FIGURE V-24 US OECD DATA APPLIED TO VOLLENWEIDER (1976) PHOSPHORUS LOADING AND MEAN DEPTH/HYDRAULIC RESIDENCE TIME RELATIONSHIP (TAKEN FROM RAST AND LEE, 1973) 72 ------- Big Reservoir Available Data (all values are means): Length 2.0 mi = 3.22 km Width 5. mi = .805 km Depth (Z) 200 ft - 20 m Inflow (Q) 50 cfs = 1.42 cms Total phosphorus concentration in water column 0.482 ppm Total nitrogen concentration in water column 2.2 ppm Total phosphorus concentration in the inflow 1.0 ppm In order to apply the plot in Figure V-24, the first step is to make as certain as possible that algal growth is phosphorus limited. In this case, the weight to weight N:P ratio is 2.2/.4S = 4.6. Presumably, algal growth in Big Reservoir is not phosphorus limited, and the Vollenweider relationship for phosphorus is not a good one to use. In this case a rigorous model should be used. If nitrogen fixation is observed to occur (heterocystous blue-green algae), an estimate of the potential problem can be obtained by assuming phosphorus to be limiting: V - 3220m • 805m • 20m = 51.8 million m3 1.42 m3 86400 sec 365 day .865 D = - — — - • - * - - sec 51.8Mm3 day yr yr T =1.16 years K = VD = 0.93 P = PI = 0.482 mg/1 D + K 2 Lp - Q • PI/A = 17.3 g/m2 yr q = Q/A = Z/TW = 20/1.16 = 17.2 m/yr 73 ------- Plotting Lp and q on Figure V-24 shows that the reservoir could be extremely eutrophic. — -END OF EXAMPLE V-10 •EXAMPLE V-ll Bigger Reservoir and The Voile nwe i d er Re1 at i on ship The physical characteristics of Bigger Reservoir are: Bigger Reservoir Available Data (all values are means): Length 20 mi = 32.2 km Width 10 mi - 16.1 km Depth (Z) 200 ft = 61 m Inflow (Q) 500 cfs Total phosphorus concentration in inflow 0.8 ppm Total nitrogen concentration in inflow 10.6 ppm As in the preceding example, first determine whether phosphorus is likely to be growth limiting. Since data are available only for influent water, and since no additional data are available on impoundment water quality, N:P for influent water will be used. \ r>/? '- 7 ^ -JxSvXj-^^- i ' N:P = 10.6/0.8 = 13.25 Thus algal growth in Bigger Reservoir is probably phosphorus limited. Compute the approximate surface area, volume and the hydraulic residence time. Volume (V) = 20 mi x 10 mi x 200 ft x 52802 = 1.12 x 1012ft3 = 3.16 x 1010m3 74 ------- Hydraulic residence time ( TW) = V/Q = 1.12 x 1012ft3/500 ft'sec"1 = 2.24 x 109sec = 71 yr Surface area (A) = 20 mi x 10 mi x 52802 = 5.57 x 109ft2 = 5.18 x 10V Next, compute q "s • q = 61 m/71 yr = 0.86 m yr'1 Compute annual inflow, Q J Q = Q x 3.15 x 107' sec yr"1 y Qy = 1.58 x 1010ft3 yr"1 Phosphorus concentration in the inflow is 0.8 ppm or 0.8 mg/1. Loading (Lp) in grams per square meter per year is computed from the phosphorus concentration, in mg/1: Lp , 28.3U x _LJL x O.Smg x - 1 - x 1>58xloio ft ft3 lOOOmg * 5.18xlOBM2 yr -? -1 Lp = 0.70 gm yr Now, referring to the plot in Figure V-23, we would expect that Bigger Reservoir is eutrophic, possibly with severe summer algal blooms. -END OF EXAMPLE V-ll" 75 ------- •EXAMPLE V-12 The Vollenweider Relationship Using Monthly Inflow Quality Data Is Frog Lake eutrophic? Frog Lake's physical characteristics are as shown below: Frog Lake Available Data: Mean length 2 mi Mean width 1/2 mi Mean depth 25 ft Available Inflow Water Quality Data: Q (monthly mean, cfs) Total P (mg/1) Inorganic N (mg/1) Month October November December January February March April May June July August September 1972 50 80 40 - - 60 80 75 40 - 38 38 1974 65 90 40 - - 58 80 76 70 25 20 25 1972 0.1 0.02 0.03 - - 0.01 0.01 0.04 0.03 - 0.09 0.06 1974 0.08 0.02 0.04 - - 0.02 0.01 0.05 0.08 0.11 0.04 0.05 1972 7.2 6.3 3.1 - - . 2.0 2.3 0.55 1.20 - 3.50 2.80 1974 6.0 2.4 1.5 - - 1.9 0.50 0.52 1.35 2.01 1.29 1.00 76 ------- First, estimate the mean annual flow and the hydraulic residence time. To compute mean annual flow, y ni y Q - ( Z Z Q )/ Z n. where Q. . = the individual flow measurements i >J y = the number of years of data n. = the number of observations per year Q = 1050/19 = 55.3 cfs = 1.75 x 109 ft3/yr Now estimate the volume, surface area, hydraulic residence time, and qs V = 2 mi x 1/2 mi x 25 ft x 52802 = 6.97 x 108ft3 = 1.98 x 10V A = 2 mi x 1/2 mi x 52802 = 2.79 x 107ft2 = 2.59 x 106m2 T = V/Q = 6.97 x 108ft3/55.3 cfs = 1.26 x 107sec = 0.4 yr w q = 25/0.4 = 62.5 Next, calculate the weighted mean inflow phosphorus and nitrogen concentrations P and N as follows: n. n. P (or N) = ( Z Z Q. x C. .)/( Z Z Q ) 1=1 j-1 lfj lfj i=l j=l 1>J P = 43.86/1050 = 0.042 ppm N = 2671.902/1050 = 2.54 ppm The N:P ratio in the inflows is 60. Therefore if one of the two is growth limiting, it is probably phosphorus. Compute the phosphorus loading, Lp. 77 ------- L = j^-iAlJt x —-—y — x y^—^-^ x • - - x ^--i-^jy_LL_ P ft3 1000 mg £ 2.59xl06m2 yr Lp = 0.80 Now, referring to the plot in Fiqure V- 23 with Lp = 0.80 and a = 62.5, the impoundment is well into the oligotrophic region. END OF EXAMPLE V-12 5.4.5 Phosphorus Levels in Predicting Algal Productivity and Biomass Another technique, which is also based upon phosphorus loading, may be even more useful than the Vollenweider relationship because it permits summer chlorophyll _a concentrations to be estimated rather than general impoundment trophic status. The method has been advanced by several researchers including Sakamoto (1966), Lund (1971), Dillon (1974), and Dillon and Rigler (1975). Briefly, the method relates mean summer chlorophyll _a concentrations to spring mean total phosphorus. As shown in Figure V-25, the relationship is highly correlated, and a regression of the log of summer mean chlorophyll _a on the log of spring mean phosphorus is linear. Using a least squares method gives the equation of the line as (Lorenzen, 1978): log (chl _a) = 1.5 log (P)-l.l (V-15) or chl a = O.OS(P)1-5 P------- 1000- fO :ioo- Q. o or 3 X O a: UJ 10- 1.0- CO UJ o.i- • Japanese Lakes a Other Lakes a 10 100 1000 SPRING MEAN TOTAL PHOSPHORUS MG/M3 FIGURE V-25 RELATIONSHIP BETWEEN SUMMER CHLOROPHYLL AND SPRING PHOSPHORUS (FROM LORENZEN, I'NPUBLISHED) 79 ------- CO o 500 0 K 0.05 0.10 P04= (as P, mg/l) 0.15 FIGURE V-26 MAXIMAL PRIMARY PRODUCTIVITY AS A FUNCTION OF PHOSPHATE CONCENTRATION (AFTER CHIAUDANI, EIAL,, 1974) ------- carbon productivity, as in the plot in Figure V-26, may be converted to total algal biomass. Since approximate analysis of dried algae has been determined as (Stumm and Morgan, 1970): 1 0 6 2 6 s 1 1 1 6° the gravimetric factor is ywr - 2.8. Thus, maximal carbon productivity may be multiplied by 2.8 to give a rough estimate of maximal algal biomass productivity. The user should bear in mind that applying this technique can only lead to rough estimates. If it is desired to predict biomass or productivity with accuracy, more sophisticated approaches may be necessary. EXAMPLE V-13 Spring Phosphorus and Summer Chlorophyll a _3 Lake Sara mean spring total phosphorus concentration = .03 mg/1 = 30 mg/m chl a^ = O.OS(P)1-5 chl a_ = 13.1 mg/m3 algal dry biomass = 13.1 x 33 = 430 mg/m3 Maximal carbon productivity in the impoundment may be estimated from the _p _i curve in Figure V-26 to be about 1950 mgCm day or about 5460 mg dry algal O 1 biomass m'^day . Observe that the two methods may lead to contradictions. In this case, if Lake Sara is 5 meters deep, the concentration is 5460/5 = 1092 mg/m3. This does not compare well with the 430 mg/m3 value just computed, and the discrepancy reflects one inadequacy in usage of the Chiaudani curve, namely, that it really does not permit estimates of concentration to be made. The 81 ------- discrepancy also reaffirms the importance of applying good judgment in evaluating estimates and in using more than one technique. END OF EXAMPLE V-13 In the absence of measured data, the in-lake concentration (P) can be computed based on the various point and nonpoint loadings (n): n Lp = £ Q..PI, 1=1 Z (D+K) Then chlorophyll _a can be estimated as shown in the previous paragraphs. 5.4.6 Restoration Measures Control of eutrophication in lakes can be evaluated by a variety of approaches (Table V-9). Some methods are directed at external sources (PI) and others at in-lake sources (K). Changes in volume (V) and inflow (0) obviously will affect predicted results. For example, dredging will decrease the return of phosphorus for the sediments (i.e. increase K) and increase the volume (i.e. decrease D). If the input concentration (PI) is the initial variable, then source controls should be investigated. If internal sources are involved, then in-lake controls should be evaluated. In many lakes, both source and in-lake controls will be needed. Problem treatment is directed at the productivity directly. These controls are often the only alternative for many lake situations. These methods are evaluated only in a qualitative way. 82 ------- TABLE V-9 CLASSIFICATION OF LAKE RESTORATION TECHNIQUES I. Source Controls A. Treatment of inflows B. Diversion of inflows C. Watershed management (land uses, practices, nonpoint source control, regulations and/or treatments). D. Lake riparian regulation or modification E. Product modification or regulation II. In-Lake Controls A. Dredging B. Volume changes other than by dredging or compaction of sediments C. Nutrient inactivation D. Dilution/Flushing E. Flow adjustment , F. Sediment exposure and dessication G. Lake bottom sealing H. In-lake sediment leaching I. Shoreline modification J. Riparian treatment of lake water K. Selective discharge III. Problem Treatment (directed at biological consequences of lake condition) A. Physical techniques (harvesting, water level fluctutations, habitat manipulations) B. Chemical (algicides, herbicides, pesticides) C. Biological (predator-prey manipulations, pathological reactions). D. Mixing (aeration, mechanical pumps, lake bottom modification) E. Aeration (add DO; e.g. hypolimnetic aeration) 83 ------- 5.4.7 Water Column Phosphorus Concentrations The relationships described in 5.4.5 for predicting algal biomass are predicated on phosphorus levels within the impoundment. A more precise mechanism for estimating phosphorus lake concentrations based on interactions between bottom sediments and overlying water has been developed. Lorenzen, e_t al. (1976) developed a phosphorus budget model (Figure V-27) which may be used to estimate water column and sediment bound phosphorus in a fully mixed system. A mass balance on both sediment and water column phosphorus concentrations yields the coupled differential equations: dC , M K AC K, AC C Q __ dt dt C = average annual total phosphorus concentration in water w column (g/m3) C = total exchangeable phosphorus concentration in the sediments (g/m3) total annual phosphorus loading (g/yr) lake volume (m3) V = sediment volume (m3) A = lake surface area (m2) - sediment area (m2) Q = annual outflow (m3/yr) KL = specific rate of phosphorus transfer to the sediments (m/yr) K2 = specific rate of phosphorus transfer from the sediments (m/yr) K3 = fraction of total phosphorus input to sediment that is unavailable for the exchange process 84 ------- C(w) Q(o) CO cn Sediir.ent FIGURE V-27 CONCEPTUALIZATION OF PHOSPHORUS BUDGET MODELING (LORENZEN ET AL,, 1976) ------- When the differential equations relating water column phosphorus to the various controlling phenomena are solved analytically, the following equation results for steady-state water column phosphorus concentration: (V-19) " Cv N rt I + * 3 Q or r - M (V-20) Cw- Q + K^H where C = steady-state water column phosphorus concentration in ppm w C. = steady-state influent phosphorus concentration in ppm in The steady-state sediment phosphorus concentration is then given by: C = - _ K2(l + (K-iKsA/QjT It is important to observe that these relationships are valid only for steady-state conditions. Where phosphorus loading is changing with time, where sediment deposition or physical characteristics are changing, or where there are long-term changes in physical conditions, the steady-state solutions are not applicable. Lorenzen applied the model to Lake Washington data and obtained very good results. With their data set, the most satisfactory coefficients had the following values: Kj = 43 m/yr K2 = 0.0014 m/yr K3 = 0.5 It should be recognized, however, that this model is relatively untested and that coefficient values for other impoundments will vary from those cited here. 86 ------- _ f/75ft3 0.15 mg\ /22ft?- x .07 mg\ / 5ft3 .21 m M - 3ec~x i+ -seT~x £ + \ sic~ x £ 28.3U y 1 g 3.16x107sec ft 1000 mg x yr M = 1.24x10 7 gP yr 7.J (75+22+5)ff3 3.16x107sec _ 3.22xlQ9ft3 _ 9.13x107m: - sec yr " yr yr 'm^yr" ' 95-6 ^s = 168/95.6 » 1.76 m yr"1 Compute phosphorus loading: 1 24x107 n vr -? -1 Lp = i.^xiu g yr = Q>24 gm ^yr l 5.2xl07 m2 Referring to Figure V-24 with q = 1.76 and Lp = 0.24, one can see that this lake may have eutrophication problems under pre-diversion conditions. After the diversion, T = 8.73x109m3 = 125 yr w ~6.98xl07m3/yr Assuming the lake depth is not materially changed over the short term, qs - 168/125 = 1.34 ^ For the new conditions, M = 8.33 x 106 gP yr"1 89 ------- Lp = g.33xl06 5.2xl07 m2 Now, according to the Vollenweider plot (Figure V-24), this is in the region between "dangerous" and "permissible" - the mesotrophic region. Under the new circumstances, algal blooms are less likely than before the flow diversions were established, but blooms are by no means to be ruled out. Turning now to an estimate of algal biomass under pre-diversion conditions, we must calculate the inlake concentration (P). First, D = I/TW = 1/125 = 0.008; K = VD = 0.09 Since our data are already in the loading form: P = ' Z \168/ \07008+0.09 Based on chlorophyll a, chl A = chl A = 0.08 (15)1'5 - 4.6 mg/m3 Dry algal biomass - 4.6x33 = 150 mg/m3 Under post-diversion conditions, p = (isr) (ooskof) = 10 chl a = 0.08 (10)1'5 = 2.5 mg/m3 Dry algal biomass = 2.5x33 = 83 mg/m 90 ------- Note that these low levels of chlorophyll ------- 5.5 IMPOUNDMENT DISSOLVED OXYGEN Organic substances introduced into an impoundment with inflowing water, falling onto its surface, or generated in the water column itself through photosynthesis, may be oxidized by indigenous biota. The process consumes oxygen which may, in turn, be replenished through surface reaeration, photosynthetic activity, or dissolved oxygen in inflowing water. The dynamic balance between DO consumption and replenishment determines the net DO concentration at any point in time and at any location within the water column. These processes result in characteristic dissolved oxygen (DO) concentrations in the water columns of stratified lakes and reservoirs (Figure V-28). During stratification, typically during summer months, the DO is highest on the surface due to photosynthesis and reaeration. It decreases through the thermocline and then, in the hypolimnion, the DO decreases to zero in those lakes that have high organic matter concentrations. During spring, after turnover, when lakes are not stratified, the DO is essentially uniform. However, in highly organic lakes benthic processes can already begin to deplete oxygen from lower depths, as shown in Figure V-28. Essentially, the patterns result from processes that are restricted due to incomplete mixing. The overall effects of such patterns as shown in Figure V-28, are to restrict fishery habitat and create water quality problems for downstream users, especially for deep water discharge. 92 ------- o •- 10 CO Dissolved Oxygen, mg/1 FIGURE V-28 TYPICAL PATTERNS OF DISSOLVED OXYGEN (DO) IN HYRUM RESERVOIR (DRURY, EI AL,^ 1975) ------- BOD exertion is not the only sink for DO. Some important sources and sinks of impoundment dissolved oxyqen are listed below: SOURCES AND SINKS OF IMPOUNDMENT DISSOLVED OXYGEN Sources Sinks Photosynthesis Atmospheric reaeration Inflowing water Rainwater Water Column BOD Benthic BOD Chemical oxidation Deoxygenation at surface Plant and animal respiration Many of the processes listed above have a complex nature. For example, the atmospheric reaeration rate is dependent in part upon the near-surface velocity gradient over depth. The gradient, in turn, is influenced by the magnitude, direction, and duration of wind, as well as the depth and geometry of the impoundment. Photosynthetic rates are affected by climatological conditions, types of cells photosynthesizing, temperature, and a number of biochemical and biological factors. Exertion of BOD is dependent upon the kind of substrate, temperature, dissolved oxygen concentration, presence of toxicants, and dosing rate. Despite this degree of complexity, a number of excellent models of varying degrees of sophistication have been developed which include simulation of impoundment dissolved oxygen. 5.5.1 Simulating Impoundment Dissolved Oxygen Because an unstratified impoundment generally may be considered as 94 ------- a slow-moving stream reach, only stratified impoundments are of interest here. For estimating DO in unstratified impoundments, one should refer to the methods described in Chapter 4. To understand the phenomena affecting dissolved oxygen in a strati' fied impoundment and to gain an appreciation of both the utility and limitations of the approach presented later, it is useful to briefly examine a typical dissolved oxygen model. Figure V-29 shows a geo- metric representation of a stratified impoundment. As indicated in the diagram, the model segments the impoundment into horizontal layers. Each horizontal layer is considered fully mixed at any point in time, and the model advects and diffuses mass vertically into and out of each layer. The constituents and interrelationships modeled are shown schematically in Figure V-30. The phenomena usually taken into account in an impoundment DO model include: • Vertical advection • Vertical diffusion • Correction for element volume change • Surface replenishment (reaeration) • BOD exertion utilizing oxygen • Oxidation of ammonia • Oxidation of nitrite • Oxidation of detritus • Zooplankton respiration • Algal growth (photosynthesis) and respiration f DO contribution from inflowing water • DO removal due to withdrawals Many of the processes,are. complex and calculations in detailed models involve simultaneous solution of many cumbersome equations. 95 ------- tributary inflow evaporation tributar inflow vertical advection control slice outflow FIGURE V-29 GEOMETRIC REPRESENTATION OF A STRATIFIED IMPOUNDMENT (FROM HEC, 1974) 96 ------- A Aeration B Bacterial Decay C Chemical Equiforium E Excreta G Growth M Mortality P Photosynthesis R Respiration S Settling H Harvest FIGURE V-30 QUALITY AND ECOLOGIC RELATIONSHIPS (FROM NEC, 1974) 97 ------- Among the processes simulated are zooplankton-phytoplankton interactions, the nitrogen cycle, and advection-diffusion. Thus it is clear that a model which is comprehensive and potentially capable of simulating DO in impoundments with good accuracy is not appropriate for hand calcu- lations. A large amount of data (coefficients, concentrations) are needed to apply such a model, and solution is most easily done by computer, Furthermore, some of the terms in the model equation of state do not improve prediction under some circumstances. This is true, for example, where there are no withdrawals or in an oligotrophic impoundment where chlorophyll a_ concentrations are very low. Hand calculations must be based upon a greatly simplified model to be practical. Since some DO-determining phenomena are more important than others arid if some assumptions are made about the impoundment itself, it is feasible to develop such a model, 5.5.2 A Simp1 if ied Impoundment_DijsoJ ved_ ^xy^en__ModeT_ For purposes of developing a model for hand calculations, the following assumptions are made: * The only condition where DO levels may become dangerously low is in an impoundment hypolimnion and during warm weather. » Prior to stratification, the impoundment is mixed. After strata form, the epilimnion and hypolimnion are each fully mixed. • Dissolved oxygen in the hypolimnion is depleted essentially through BOD exertion. Significant BOD sources and sinks to the water column prior to stratification are algal mortality, BOD settling, and outflows. A minor source is influent BOD. Following formation of strata, sources and sinks of BOD are BOD settling out onto the bottom, water column BOD at the time 98 ------- of stratification, and benthic BOD. • Photosynthesis is unimportant in the hypo! imn ion as a source of DO. * Once stratification occurs (a tnermocline gradient of 1°C or greater per meter of depth) no mixing of thermo- cline and hypolimnion waters occurs. • BOD loading to the unstratified impoundment and to the hypolimnion are in steady-state for the computation period. 5.5.2.1 Estimating a Steady-State BOD Load to the Impoundment - Equation V-25 is an expression to describe the rate of change of BOD concentration as a function of time: — - ' k k r - k C - ^- (V- dt " a kSC 1 V { where C = the concentration of BOD in the water column in mgl" k = the mean rate of BOD loading from all sources in mgl" day" 3 k = the mean rate of BOD settling out onto the impoundment 5 _T bottom in day k, = the mean rate of decay of water column BOD in day" 0 = mean export flow rate in liters day V = impoundment volume in liters 99 ------- Integrating Equation V-25 gives: (k + k c }^kh> \t a kbVe. b - ka (V-26) kb where C, = concentration of BOD at time t CQ = initial concentration of BOD kb = -ks-kr v To estimate the steady-state loading of BOD, we set dc/dt = 0 and obtain Css = - k^ (V-27) where GSS = steady-state water column BOD Thus Equation (V-27) may be used to estimate a steady-state water column BOD concentration and Equation (V-26) may be used to compute BOD as a function of time, initial concentration of BOD, and the various rates. 5.5.2.2 Rates of Carbonaceous and Nitrogenous Demands The rate of exertion of BOD and therefore the value of k, is dependent upon a number of physical, chemical, and biological factors. Among these are temperature, numbers and kinds of microorganisms, dissolved oxygen concentration, and the kind of organic substance in- volved. Nearly all of the biochemical oxygen demand in impoundments is related to decaying plant and animal matter. All such material consists essentially of carbohydrates, fats, and proteins along with a vast number of minor constituents. Some of these are rapidly utilized by bacteria, for example, the simple sugars, while some, such as the celluloses, are metabolized slowly. Much of the decaying matter in impoundments is carbonaceous. 100 ------- ns Carbohydrates (celluloses, sugars, starches) and fats are essentially devoid of nitrogen. Proteins, on the Qther hand, are high in nitrogen (weight of carbon/weight of nitrogen - 6) and protein: therefore represent both carbonaceous and nitrogenous demands. The rate of exertion of carbonaceous and nitrogenous demands differ. Figure V-31, which shows the difference graphically and as a function of time and temperature, may be considered to represent the system response to a slug dose of mixed carbonaceous and nitrogenous demands. In each two-section curve, especially where concentrated carbonaceous wastes are present, the carbonaceous demand is exerted first, and this represents the first stage of deoxygenation. Then nitrifiers increase in numbers and ammonia is oxidized through nitrite and ultimately to nitrate. This later phase is called the second phase of deoxygenation. BOD decay (either nitrogenous or carbonaceous alone) may be repre- sented by first order kinetics. That is, the rate of oxidation is directly proportional to the amount of material remaining at time t. dC . .r (V-28) dt ' "KU The rate constant, k, is a function of temperature, bacterial types and numbers, composition and structure of the substrate, presence of nutrients and toxicants, and a number of other factors. The value of the first stage constant k, was first determined by Phelps in 1909 for sewage filter samples. The value was 0.1 (Camp, 1968). More recent data show that at 20°C, the value can range from 0.01 for slowly metabolized industrial waste organics to 0.3 for relatively fresh sewage (Camp, 1968). The typical effect of temperature on organic reactions is to double reaction rates for each temperature rise of 15°C. The relationship for correcting k-, for temperature is: 101 ------- 201 CD cr 70 rn OO CO ^3 H X > > O H CD s m m •—< co z o CD TI m dd CD ~n m — • x TO m CO PD > o z 2: a > CVO H m o C3 o •— a m m m o -z. X H CD -H m m H m •— xj o > Z H m CO Oxygen Used up Parts per Million ------- = kl,(20°C) where T = the temperature of reaction 8 = correction constant = 1.047 However, Thereault has used a value for fl of 1.02, while Moore calculated values of 1.045 and 1.065 for two sewages and 1.025 for river water (Camp, 1968). Streeter has determined the rate of the nitrification or second deoxygenation stage in polluted streams. At 20°C, k-j for nitrification is about 0.03 (Camp, 1968). Mobre found the value to be .06 at 20°C and .035 at 10°C (Camp, 1968). For purposes of this analysis, BOD exertion will be characterized as simple first order decay using a single rate constant. Benthic demand, which is important in later computations, may vary over a wide range because in addition to the variability due to the chemical nature of the benthic matter, rates of oxidation are limited by upward diffusion rates of oxidizable substances through pores in the benthos. Since the nature of the sediment is highly variable, benthic oxygen demand rates vary more than values for k, in the water column. In a study using sludges through which oxygenated water was passed, initial rates of demand ranged from 1.02 g/nr day 2 (see Table V-10) for a sludge depth of 1.42 cm up to 4.65 g/m day for a sludge depth of 10.2 cm (Camp, 1968). In that study, the values found were for initial demand since the sludge was not replenished. The rate per centimeter of sludge depth, then, can vary from a low of 2 ? 0.46 g/m day for 10.2 centimeter depth sludge up to 0.76 g/m day for 1.42 centimeter depth sludge. 103 ------- TABLE V-10 OXYGEN DEMAND OF BOTTOM DEPOSITS (AFTER CAMP, 1968) Benthic Depth (mean) cm 10.2 4.75 2.55 1.42 1.42 Initial Vol ume of _~ Solids, kqm 3.77 1.38 0.513 0.188 0.188 Initial Area Demand L (gin"2) 739 426 227 142 134 initial Derr.and -2 -1 am day 4.65 3.09 1.70 1.08 1.02 day'1 k4(20°C) .0027 .0031 .0032 .0033 .0033 The constant loading rate (k ) used in Equation (V-25) is best esti- a mated from historical data. Alternatively, inflow loading (see Chapter IV) and algal productivity estimates (this chapter) may be used. In the latter case, a value must be adopted for the proportion of algal biomass ultimately exerted as BOD. To a first approximation, k may a be estimated using this value and adopting some percentage of maximal primary productivity (see Figure V-25). Thus, where ka(algae) = SMP x 10"3/D (V-30) ka(algae) = algal contribution to BOD loading rate S = stoichiometric conversion from algal biomass as carbon to BOD = 2.67 M = Proportion of algal biomass expressed as an oxygen demand (unit!ess) -2 1 P = Primary production in mgCm day 104 ------- The difference between algal biomass and the parameter M repre- senting the proportion of algal bio-mass exerted as BOD may be conceptu- alized as accounting for such phenomena as incorporation of algal bio- mass into fish tissue which either leaves the impoundment or is harvested, , loss of carbon to the atmosphere as CH., and loss due to outflows. The settling rate coefficient, k in Equation (V-25) must be esti- mated for the individual case. It represents the rate at which dead plant and animal matter (detritus) settles out of the water column prior to oxidation. Clearly, this coefficient is sensitive to the composition and physical characteristics of suspended matter and the turbulence of the system. Quiescence and large particle sizes in the organic fraction will tend to give high values for k while turbulence and small organic fraction particle sizes will give small values for k . 5.5.2-3 Estimating aPre-Stratification Steady-State Dissolved Oxygen Level Prior to stratification, the impoundment is assumed to be fully mixed. One of the important factors leading to this condition is wind stress, which also serves to reaerate the water. As a ru.le, unless an impoundment acts as a receiving body for large amounts of nutrients and/or organic loading, dissolved oxygen levels are likely to be near saturation during this period (D.J. Smith, pers. comm., November, 1976). Table V-ll shows saturation dissolved oxygen levels for fresh water as a function of temperature, and DO levels may be estimated accordingly. The hypolimnetic saturation dissolved oxygen concentration is determined by using the average (or median) temperature for the hypolimnion as determined during the period of interest throughout the depth of the hypolimnion. Information on the hypolimnion are obtained using the procedures described in Section 5.2. For example, hypolimnetic water at the onset of stratification might be 4-5°C and during the critical summer months be 10 C. The value 10°C should be used having a saturation DO of 11.3 mg/1. 105 ------- TABLE V-ll SOLUBILITY OF OXYGEN IN WATER (STANDARD METHODS, 1971) Chloride Concentration Temp. in °C 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 0 5,000 10,000 in Water - mg/1 15,000 Sea Water Difference per 100 mg Chloride Dissolved Oxygen - mg/1 14.6 13.8 14.2 13.4 13.8 13.1 13.5 12.7 13.1 12.4 12.8 12.1 12.5 11.8 12.2 11.5 11.9 11.2 11.6 11.0 11.3 10.7 11.1 10.5 10.8 10.3 10.6 10.1 10.4 9.9 10.2 9.7 10.0 9.5 9.7 9.3 9.5 9.1 9.4 8.9 9.2 8.7 9.0 8.6 8.8 8.4 8.7 8.3 8.5 8.1 8.4 8.0 8.2 7.8 8.1 7.7 7.9 7.5 7.8 7.4 7.6 7.3 7.5 7.4 7.3 7.2 7.1 13.0 12.6 12.3 12.0 11.7 11.4 11.1 10.9 10.6 10.4 10.1 9.9 9.7 9.5 9.3 9.1 9.0 8.8 8.6 8.5 8.3 8.1 8.0 7.9 7.7 7.6 7.4 7.3 7.1 7.0 6.9 12.1 11.8 11.5 11.2 11.0 10.7 10.5 10.2 10.0 9.8 9.6 9.4 9.2 9.0 8.8 8.6 8.5 8.3 8.2 8.0 7.9 7.7 7.6 7.4 7.3 7.2 7.0 6.9 6.8 6.6 6.5 11.3 11.0 10.8 10.5 10.3 10.0 9.8 9.6 9.4 9.2 9.0 8.8 8.6 8.5 8.3 8.1 8.0 7.8 7.7 7.6 7.4 7.3 7.1 7.0 6.9 6.7 6.6 6.5 6.4 6.3 6.1 0.017 0.016 0.015 0.015 0.014 0.014 0.014 0.013 0.013 0.012 0.012 0.011 0.011 0.011 0.010 0.010 0.010 0.010 0.009 0.009 0.009 0.009 0.008 0.008 0.008 0.008 0.008 0.008 0.008 0.008 0.008 106 ------- Most lakes are near sea level (<2000 ft elevation) and are relatively fresh (<2000 mg TDS/1). For lakes that do not meet these criteria, corrections for atmospheric pressure differences and salting out due to salinity might be needed. Pressure effects can be approximated by using a ratio of barometric pressure (B) for the elevation of interest and sea level (BSTP) as follows: e.g. B at 4600 ft elevation, . in mm Hg. = 0.84 DOsat at 10°C = 0.84 x 11.3 =9.5 mg/1 . Chloride is an estimator of dilutions of sea water in fresh water where 20000 mg Chloride/1 is equivalent to 35000 mg salt (TDS/1, that is, typical ocean water. 5.5.2,4 Estimating Hypolimnion DO Levels The final step in use of this model is preparation of a DO- versus-time plot for the hypolimnion (or at least estimation of DO at incipient overturn) and estimation of BOD and phosphorus loadings which result in acceptable hypolimnion DO levels. An equation to compute DO at any point in time during the period of stratification is dt T where 0 = dissolved oxygen in ppm -1 k. = benthic decay rate in day' L = area! BOD 1 D = depth in m _2 L = area! BOD load in gm The second term in the equation requires that an estimate be made of the magnitude of BOD loading in benthic deposits. To do this within the present framework, it is assumed that BOD settles out ... 107 ------- throughout the period of stratification. Although many different assumptions have been made concerning benthic BOD decay, it was assumed that benthic demand was a function of BOD settling and the rate of benthic BOD decay. This BOD includes that generated in the system by algal growth and that which enters in tributaries and waste discharges. Based upon the rate of settling used earlier in estimating a steady-state BOD concentration (Equation (V-25)) and rate of decay for conditions prior to stratification, the rate of benthic matter accumulation is: dT = ksCssD-k4L where C = concentration of BOD in the water column in gm at steady-state The assumption of steady-state BOD concentration reduces Equation (V-32) to the same form as Equation (V-25) and integration gives: , . For steady-state deposition (dL/dt = 0, Dkscss= constant), ksCssD Lss » -VS- (V-34) where _2 L = steady-state benthic BOD load in gm Application of Equation (V-34) with k and k. appropriately chosen for the month or two preceding stratification will give an estimate of the benthic BOD load upon stratification. Application 108 ------- of Equation (V-33) gives the response of L to different water column BOD (steady-state) loading rates and changes in rate^ coefficients. After strata form, benthic matter decays while hypolimnion water column BOD decays and settles. The change in L over the period of stratification is HF = -k4L * Dksc (V-35) Since dC and Ct = Co e"(l<1 + ^^ (v-37) ^= -k4L + DksCQ e-(kl + ksH (V-38) Water column BOD in the hypolimnion is given by Equation (V-36) and the integrated form is Equation (V-37). Note that k , the settling coefficient is equal to v /D where o o v is the settling velocity of the BOD, and D is the depth of the hypolimnion (or when the impoundment is unstratified, D is the depth of the entire impoundment). Also note that we usually assume that the DO is at saturation at the onset of stratification. Thus we can ignore the assumptions and calculations (Equation V-32 to V-34) done for periods prior to onset. 109 ------- The equation presented earlier (Equation V-31) for hypo limn ion DO was: HT = -k!C -k4L/D Equation (V-31) is not integrable in its present form, but since L and C are defined as functions of t (Equations (V-39) and (V-37) respectively), it is possible to determine dissolved oxygen in the water column. The equation for oxygen at time t is: °t = °o " AOL " A0c where 0 = dissolved oxygen at time t 0 = dissolved oxygen at time t = 0 AO, = dissolved oxygen decrease due to benthic demand AOC = dissolved oxygen decrease due to hypolimnion BOD From Equation (V-39), and using L as L and C as C , (V-4T) and from Equation (V-37), (V-42) Solution of Equation (V-40) gives an estimated DO concentration in the hypolimnion as a function of time. 110 ------- To compute equation (V-40), a simpler form of equation (V-41) can be derived by substituting as follows: since k C D _ ss ss , "ss AO. To simplify computations, the following stepwise solutions can be made: A = ksCss ks+krk4 Then, B - C = E = r _ " kl Css kl+ks L = A ( AO = B - c - A0 - E - F 111 ------- 5.5.3 Temper ;atu re Correct ions All reactions are computed on the basis of the optimum temperature, but the environment is often at different temperatures. Some rate coefficients for chemical and biological reactions vary with temperature. A simple correction for such rate coefficients to 20°C is as follows: K = K x 1 047 (T - 20°C) T T20 X 1'U4/ For example, if a rate at 20 C = 0.01 and the lake is at 10°C, then K = 0.01 x 1.047 (10 - 2°) KT = 0.00632 Generally the following optima are used: ki - first order decay rate for water column BOD, use 20°C. ki» - benthic BOD decay, use 20°C. P - productivity rate, use 30° C. In the screening methods we do not have to correct for temperature except in the oxygen calculation for the rate coefficients, Kj , K4, P and in the toxics section (5.6) for the biodegradation rate coefficients. 112 ------- EXAMPLE V-15 Quiet Lake (Comprehens i ve Examp1e) Quiet Lake is located a few miles south of Colton, New York. The lake is roughly circular in plan view (Figure V-32) and receives inflows from three tributaries. There is one natural outlet from the lake and one withdrawal used for quarrying purposes. The first step in evaluation of lake hypolimnion DO levels is physical and water quality data collection. Table V-12 shows characteristics of Quiet Lake, Table V-13 shows tributary discharge data along with withdrawal and outflow levels, and Table V-14 provides precipitation and runoff information. In order to evaluate hypolimnion DO as a function of time, the' very first question to be answered is, does the impoundment stratify? If so, what are the beginning and ending dates of the stratified period, how deep is the upper surface of the hypolimnion, and what is its volume, and what is the distribution of hypblimnion mean temperatures during the period? To answer these questions, either use field observation data, or apply some computation technique such as that presented earlier in this section. Assuming that methods presented earlier are used, the selection of appropriate thermal profile curves hinges around three factors. These are • Climate and location • Hydraulic residence time, and • Impoundment geometry 113 ------- SUUSVILLE QUIETOWN Ol PUMP HOUSE [-1 STREAM QUALITY "—' AND FLOW STATION RUNOFF QUALITY SAMPLING STATION SAMPLES TAKEN FROM SMALL EROSION CHANNELS NEAR LAKE FIGURE V-32 OUIET LAKE AND FNVIRONS 114 ------- TABLE V-12 CHARACTERISTICS OF QUIET LAKE Length (in di Width Mean Depth Maximum Depth Water Column Quiet Lake rection of flow) P TABLE V-13 3.5 miles 4.0 miles 22 ft. 27 ft. = 18,480 ft. = 21,120 ft. 0.014------- TABLE V-13 (Continued) Month October November December January February March April May June July August September Month October November December January February March April May June July August September First Creek ( Mean Flow, cfs 5 3 2 2 3 4 6 8 10 8 6 4 Second Cree Mean Clow, cfs 14.0 13.0 12.5 5.0 1.2 2.0 2.5 4.0 8.0 12.0 8.0 5.5 Station 5) Total N 1.0 2.0 0.5 1.2 1.3 2.3 2.0 1.8 1.6 1.4 1.5 0.8 k (Station 4) Total N 15 16 10 9 12 13 8 6 5 7 6 8 Total P ppm .01 .01 .02 .01 .02 .01 .01 .02 .01 .01 .00 .00 Total P ppm .15 .08 .20 .15 .12 .10 .11 .07 .08 .20 .22 .25 BOD 0.5 1.0 1.5 1.0 0.8 0.6 0.5 0.6 0.8 0.8 1.0 1.2 BOD 7 8 10 7 7 6 7 9 12 3 4 8 116 ------- TABLE V-13 (Continued) Swift River (Stations 2 and 3) and Pumped Withdrawal Month October November December January February March April May June July August September Pumped Withdrawal, cfs 22.6 22.0 3.5 1.2 0.8 0.4 12.0 24.0 30.7 89.5 29.8 43.9 Mean Monthly Station 2 69.5 50.0 20.0 7.5 1.2 9.1 44.5 63.2 100.0 168.5 80.6 91.3 Flow, cfs Station 3 77.0 55.0 '2.0 9.0 1.4 10.1 48.75 69.5 110.0 184.8 88.5 100.25 Notes: All three tributaries have their headwaters within the shed. The net inflow-outflow to the groundwater is known to be close to zero in the two creeks. Swift River is usually about 10% effluent over its entire length (10% of flow comes into the river from the groundwater table). 117 ------- TABLE V-14 PRECIPITATION AND RUNOFF DATA FOR QUIET LAKE WATERSHED VALUES ARE MEANS OF DATA COLLECTED FROM BOTH STATIONS (SEE FIGURE V-31). THE WATERSHED HAS AN AREA OF 55 SQUARE MILES INCLUDING THAT OF THE LAKE Mean Total Monthly Precipi _Month tation, inches October November December January February March April May June July August September Total 3.0 2.4 1.0 0.5 0.3 0.6 2.0 2.8 4.2 7.6 3.5 4.2 32.1 Runoff Qual ity Total N 6.0 6.5 4.0 3.0 1.0 1.5 2.5 3.2 3.6 7.0 7.8 9.2 Total P ppm 0.1 0.2 0.1 0.008 0.07 0.1 0.15 0.25 0.20 0.40 0.60 0.80 BOD 27 37 46 34 33 30 40 50 40 37 45 50 Note: Infiltration to the water table on a monthly basis accounts for roughly 30% of precipitation volume. In terms of climate and location, the Quiet Lake area is similar to Burlington, Vermont. Examination of the Burlington plots from Appendix D reveals that a 20-foot maximum depth impoundment can stratify in an area shielded from the wind. The area surrounding Quiet Lake does pro- vide good shielding, so the next task is to estimate the hydraulic residence time to select a specific set of plots. 118 ------- Inspection of all Burlington plots indicates that stratification is likely to .occur at most from May to August. Accordingly, for pur- poses of plot selection, we are most interested in a mean hydraulic resi- dence time based on flows in the period from about March to August. Since hydraulic residence time (T ) is given by T = V/Q, we compute mean Q (Q). Q represents the average of tributary inflows during this period, computed as follows: * 8+40+55+85+150+70 4+6^+10+8*-6 . 2+2.5+4•»8+12+8 Q = _ + _ , fi (Swift River) (First Creek) (Second Creek) Q = 68+7+6.08 = 81.1 cfs However, in order to fully account for mass transport as well .as properly estimate hydraulic residence time, one more factor should be considered. This is non-point inflow. At this point, we have enough information to estimate the stormwater contribution directly to Quiet Lake. In view of the available data, the computation is as follows: QS= APK(l-L)- where Q = stormwater or non-point inflow in cfs (excluding rivers and creeks) A = area of shed in square miles n = number of tributaries Q. = monthly mean pickup (in cfs) in the ith tributary P = monthly total precipitation, in inches per month I. = percent (expressed as a decimal) of flow contributed by exfiltration (from the water table into thr channel) 119 ------- L = the proportion of precipitation lost by infiltration into the soil (expressed as a decimal) K = unit correction = 0.895 ft mo mi"2in"1sec"1 As an example, the computation for October is: Q = 55 mi2 x 3.0 -J£ x 0.896 -|^-°— x (1-0.3) - nri in sec (54(1-0. l)+5(l-0.0)+14(l-0.0) + (77-69. 5)(l-0.1)j - 29.1 cfs Now, since we know the pumped withdrawal rates as well as the difference between flows at stations 2 and the sum of 1 , 4, and 5, and that the im- poundment surface is at steady-state over the mouth, we also can estimate the net infiltration rate from the lake into the groundwater. The infil- tration rate is (again, for October): Net efflux = Q(sta U4+5) -Q2+QS-QW = 73.0 - 69.5 + 29.1 - 22.6 = 10.0 cfs Note that the pickup in each channel above Quiet Lake is equal to the flow at the pertinent sampling station. This is the case because the three channels have their headwaters within the watershed. If one were concerned about a subshed with tributary headwaters above the subshed boundary, the difference in Q between each of stations 1, 4, and 5 and the respective flows at the upstream subshed boundary would be used. To estimate hydraulic residence time add the mean stormwater con- tribution over the months of interest to that of the tributaries, as computed earlier. The individual stormwater computations are not shown. The method is as just described. Q -81.1+ 120 ------- Then the hydraulic residence time is given by: = V/Q ~ Trr2D/Q v* « x 5280 where L = length of the lake in mi. W = width of the lake in mi. D = mean depth in ft. r = radius in ft. r i2 T = 3.14 x 3.5+4 5280 x 22/119 w [4 J = 5.69xl07 sec = 658 days Accordingly, the infinite hydraulic residence time plots for a 20-foot deep, wind-protected, Burlington, Vermont, impoundment should suffice. Note that the entire impoundment volume was used in the above computation. Strictly, one should use the epilimnion volume during stratification. In this case, such a change would not alter selection of the plots because T,, would still be greater than 200 days. A reproduction of the W appropriate plot from Appendix D is presented in Figure V-33., As indi- cated, Quiet Lake is likely to be weakly stratified from May to August inclusive, with a thermocline temperature gradient of about l°ft" . The hypolimnion should extend downward to the bottom from a depth of about 3-1/2 meters, giving a mean hypolimnion depth of 22 ft - 3.5 m = 3.2 meters -- " 3.28 ft nf ' 121 ------- 0 2 jr x Q_ UJ a 6c »r« nn, 2 zr x: a. CD 6 JUL n r •• 2 • x: x t— Q. UJ a 4 • g 0 To TEMP / / / / 20 . C NQV 3 C 0 2 x; X a. UJ Q 4 • 6o ) 10 20 3 TEMP, C sue / / I'D 2'0 3 TEMP. C 2 X 0_ Q G 0 C 0 2 • sr x Q_ UJ a 4 . 6o / / 1 I 10 20 3 TEMP, C SEP 10 20 3( TEMP. C 2 zr x a. LU O 4 • o c c 0 2 X a_ 4 - . 6o / / / 1 ) 10 20 30 TEMP, C OCl 10 20 30 TEMP. C DEC 10 TEMP 20 . C 2 X Q_ a 4 1 BURLINGTON, VERMONT 20* INITIRL MRXIMUM DEPTH INFINITE HYDR. RES- TIME MINIMUM MIXING 30 0 10 20 30 TEMP. C FIGURE V-33 THERMAL PROFILE PLOTS FOR USE IN QUIET LAKE EXAMPLE 122 ------- The approximate hypolimnion volume, then, is v«= i x VTotai x 1.9X1011*, = 9.2xl010S< Over the period of interest, the hypolimnion mean temperature dis- tribution is: Mean Month March 2.0 April 5.5 . . May 9.5 June 12.5 July 14.0 August 15.5 The next step in use of the DO model is to determine a steady- state or mean water column BOD loading (k ) and DO level prior to stratifi a cation. This is a multi-step process because of the several BOD sources. The sources are tributaries, runoff, and primary productivity. First, we estimate algal productivity using methods of this chapter (or better, field data). Using the curve in Figure V-26 and phosphorus data from Table V-13, the maximal primary productivity should be in the range 1,400 mg -2 -1 -2-1 11 Cm day to 1,900 mgCm day . To convert to loading in mgl day , divide by (1000 1m x 6.7m). This gives the loading as 0.21 to 0.28 mgl" day" . 123 ------- Now assuming that maximal productivity occurs at about 30°C and that productivity rates obey the same temperature rule as BOD decay, temperature-adjusted estimates of productivity rates can be made. Using the maximal rate range of 0.21 to 0.28 mgl" day" , the adjusted rates are: Productivity = (0.21, 0.28) x 1 .04?(3-75-30) = (.06, .08) mgl"1 day"1 Then, according to Equation (V-30) and assuming M = 1 , k, due to algae a is estimated by: k (algae) = 2.67 x (.06, .08) = (.16, .21) mgl^day"1 a The next contributor to water column BOD is BOD leading of inflow- ing waters. The value to be computed is the loading in milligrams per liter of impoundment water per day. / " LI \ /" Daily BOD loading rate = \ I I d-Q- . C. . I / VZ d, \i = l j=l 1 1)J 1>J/ / k=l k where n' = the number of time periods of measurement V = volume of impoundment in liters d = the number of days per time period L = the number of inflows For all inflows, the value is therefore approximately: ka(Trib) = (2185 + 48'3 + 643'9 + 14240) x 2'45xl°6 x 117 = °'22 (Swift (First (Second (Storm (Units (Impound- River) Creek) Creek) water Conversion) ment Runoff) Volume) Now, summing the two contributions: ka = ka(algae) + ka(Trib) k = (.16, .21) + .22 = (.38, .43) mgl^day"1 a 124 ------- The value of k, will be assumed as 0.1 at 20°C with 9 in Equation (V-29) equal to 1.047. Then at 3.75°C, kl(3.75°C)=kl(20°C) xl = .1 x 1.047(~16'25) = 0.047 Now Q( discharge) (mean for March and April) and V are known, with Q(discharge) = 26'8 (Sw1ft River' Stat1on 2> + 6.2 (pumped withdrawal) x 28'^2A = 935£ sec"1 ftj V = 1.9 x TO11*, Then C = _ -38' -43 _ = 4 94 5 58 55 (.03+.047+(935/1.9xl011)) For further computations, C = 5.25 will be assumed. Since k has been defined as .03, a steady-state areal concentra- tion of benthic BOD prior to stratification can be estimated. If k4(20°C) = '°03 and Css = 5<25' usin9 Equation (V-34), ksCssD -ss " k 4(3.75°C) k4(3 75°C) = -003x1. 047(3'75"20) = -0014 i .03x5.25x6.7 7,. -2 Lss= - - = 754 The next step in evaluating hypolimnion DO depression is to estimate pre-stratification DO levels. If we assume saturation at the mean temperature in April (5.5°C), the dissolved oxygen concentration at onset of strata should be about 12.7 (from Table V-ll). 125 ------- Now-we have all values needed to plot hypolimnion DO versus time using Equations (V-40) through (V-42). Using L0 = LS$ Co = Css k, = O.lxl.047(9'5~20) = .062, (T = 9.5°C for May) ks = 0.03, k4 = .003x1. 047(9<5~20) = .002, and t = 5 days , and applying Equation (V-42), AH 0.062x5.25 , -(0. 062+0. 03)5 A0c " 0.062x0.03 Then, according to Equation (V-41 ) , L kC kC k4 /754 . 0.03x5.25 \ /, -0.002x5 \ / 0.03x5.25 \ L= I 372 0.03+0.062-0.002 H / ^0.03+0.062-0.002J I 0.002 \ L -(0.062+0.03)5)= 2.35 (0.062+0.03 I l'"e / Then from Equation (V-40) °t = °o - 0, = 12.7 - ^- - 1.94 = 10.26 0 D . / Solving the same equations with increasing t gives the data in Table V-15. 126 ------- If it has been necessary to develop more data for the remainder of the stratified period, appropriately updated coefficients might be used starting at the beginning of each month. TABLE V-15 DO SAG CURVE FOR QUIET LAKE HYPOLIMNION Date t = 0 5/5 5/10 5/15 5/20 5/25 AOL 0 2.35 4.68 6.99 9.22 11.54 AOC 0 1.30 2.13 2.65 2.98 3.18 °t 0 9.05 5.89 3.06 0.50 0.00 Finally, if it is desired to evaluate the impact of altered BOD or phosphorus loadings, the user must go back to the appropriate step in the evaluation process and properly modify the loadings. END OF EXAMPLE V-15 ' 127 ------- 5.6 TOXIC CHEMICAL SUBSTANCES Although reasonably accurate and precise methods have been prepared for screening only a few of the many priority pollutants (Hudson and Porcella, 1981), a reasonable approach for assessing priority pollutants in lakes based on the methods presented in Chapter 2 can be made if certain assumptions are made: • The major processes affecting the fate and transport of toxicants in aquatic ecosystems are known. • That reasonable safety factors are incorporated by making reasonable most case analyses. t Because it is a screening approach, prioritization can be done to identify significant constituents, lakes where human health or ecological problems can realistically be expected, and processes which might require detailed study. The major processes affecting toxicants are listed in Table V-16. The primary measure of the impact of a toxic chemical in a lake depends on its concentration in the water column. Thus, these screening methods are primarily directed at fate and transport of toxic chemicals. A secondary target is the concentration in aquatic biota, principally fish. Because of the complexity of various routes of exposure and bioaccumulation processes, the approach of bioconcentration is used to identify compounds likely to accumulate in fish. These can be applied to lakes using the following method: t A fate model is used that incorporates sediment transport, sorption, partitioning, and sedimentation. • Significant processes include the kinetic effects of sedimentation, volatilization and biodegradation. 128 ------- TABLE V-16 SIGNIFICANT PROCESSES AFFECTING TOXIC SUBSTANCES IN AQUATIC ECOSYSTEMS Physical-Chemical Processes Rate Coefficient Symbol, time -1 Sorption and sedimentation Volatilization Hydrolysis Photolysis Oxidation Precipitation SED not assessed not assessed Biological Processes Biodegradation Bioconcentration B BCF (unitless) 129 ------- • Significant biochemical processes can affect the fate of a toxic chemical as well as affect biota, such, as, bioaccumulation, biodegradation, and toxicity. • In keeping with the conservative approach of the toxics screening methodology, some important processes are neglected for simplicity; for example, lake stratification, photolysis, oxidation, hydrolysis, coagulation-flocculation, and precipitation are neglected. Also, it is assumed that the organic matter is associated with inorganic particles and therefore organic matter settles with the inorganic particles. Generally the toxic chemical concentrations are calculated conservatively, that is, higher concentrations are calculated than would occur in nature because of the assumptions that are made. The water column concentrations are calculated as the primary focus of the screening method. Then bioconcentration is estimated, based on water concentration. To determine concentration and bioaccumulation, point and nonpoint source loadings of the chemicals being studied are needed. Other data (hydrology, sediments, morphology) are obtained from the problems previously done in earlier chapters or sections of this chapter. The person doing the screening would have to compile or calculate such data. Occasionally, such information must be estimated based on production, use, and discharge data. Information on chemical and physical properties is important to determine the significance of these estimates. 5.6.1 Overall Processes Several processes affecting distribution of toxic chemicals are more significant than others. Equilibrium aquatic processes include suspended sediment sorption of chemicals. Organics in sediments can have a significant effect on chemical sorption. Hydrolysis and acid-base equilibria can alter sorption equilibria. Volatilization is an equilibrium process that tends to remove toxic chemicals from aquatic ecosystems. Removal processes include settling of toxics sorbed on sediments, 130 ------- volatilization, and biodegradation. Chemical reactions for hydrolysis and photolysis are included and precipitation and redox reactions could be included if refinement of the method were desired. Generally, bioaccumulation will be neglected as a removal process. These removal processes are treated as first-order reactions that are simply combined for a toxicant (C,mg/l) to give: dC/dt = - K x C (V-44) where K = SED + B + ky + k + kh SED = sedimentation rate, toxicant at equilibrium with sediments. volatiliza' B = biodegradation rate. k = photolysis rate. kh = hydrolysis rate. k = volatilization rate. This equation is analogous to the BOD decay rate equation used in the hypolimnetic DO screening method. The input of toxic chemical substances is computed simply (refer to Figure V-23): dt = V x Cin " f (V-45) w where C. is the concentration in the inflow (tributary or discharge) and flow (Q), volume of reservoir (V) and time (t) are as defined previously. At steady state, accounting for inflow (Q-C. ) and outflow (Q-C), and using Q/V = I/TW, dT= ? (Cin - 0 - K x C = 0 (V-46) w 131 ------- and solving, C = W^1 + Tw x K> ( To determine the concentration at any time during a non-steady state condition (assuming C is a constant): C C = -^ (I - e-ft) + CQ e-ft (V-48) where f = 1 + T x K w C = reservoir concentration at t = 0. o 5.6.1.1 Sorption and Sedimentation Suspended sediment sorption is treated as an equilibrium reaction which includes partitioning between water (Cw) and the sediment organic phases (C ). The concentration sorbed on sediment can be computed as follows: Cs. = a x K x S (V-49) where C = the total concentration (Cw + Cs), mg/1 S = input suspended organic sediment = OC x So, mg/1 OC = fraction of organic carbon. So = input of suspended sediment, mg/1 K = distribution coefficient between organic sediment and water a = fraction of pollutant in solution = 1/(1 + (Kpx S) If K is large, essentially all of the compound will be sorbed onto the sediments. Note that S and C must be estimated or otherwise obtained. The organic matter content of suspended sediment and the lipid solubility of the compound are important factors for certain organic chemicals. Other sorption can be ignored for screening. A simple linear 132 ------- expression can be used to calculate the sediment partition coefficient (K ) based on the organic sediment carbon concentration (OC) and the octanol-water coefficient (kow) for the chemical: K = 0.63 (kow) (OC) P The sedimentation rate (SED) of a toxic chemical is computed as follows: SED = a x D x K (V-50) P where D = P x S x Q/V, sedimentation rate constant P = sediment trapping efficiency Q/V = I/T 5.6.1.2 Biodegradation The biodegradation rate (B) is obtained from the literature or is computed as follows: B - - Modification to the rate can be made for nutrient limitation using phosphorus (Cp) as the limiting nutrient: B (0.0277)C (v-52) Temperature correction can be performed using the following equation: B(T) = 6(20^) x 1.072(T"20) (V-53) Previous exposure to the pollutant is important for most toxic organic compounds. Higher rates of degradation occur in environments with frequent or longterm loading (discharges, nonpoint sources, frequent spills) than 133 ------- infrequent loadings (one-time spills). In pristine areas, rates of one to two orders of magnitude less should be used. It is assumed that the suspended sediment decay rate is the same as aqueous phase decay. Also benthic decay is disregarded because bottom sediment release may be negligible. 5.6.1.3 Volatilization Many organics are not volatile so this process is applied only to those which are. It is assumed that the mass flux of volatile organics is directly proportional to the concentration difference between the actual concentration and the concentration at equilibrium with the atmosphere. The latter can be neglected in lakes. Also, only the most volatile are assessed. Thus, - - ky x C (V-54) where kv = volatilization rate constant, hr The rate coefficient is derived from the 2 resistance model for the liquid-gas interface, but it can be estimated using correlation with the oxygen reaeration coefficient (based on Zison _et _al_., 1978): k = Ka (Dw/Do) (V-55) and estimate (Dw/Do) = and the surface film thickness, SFT = (200-60 - \/w~) x 10"6 and Kal = Do/SFT Ka = Kal/ZB where Ka = reaeration rate, hr~ Dw = pollutant diffusivity in water 134 ------- -9 o Do = diffusivity of oxygen in water (2.1 x 10 m2/sec, 20 C) mw - pollutant molecular weight W = wind speed, m/sec Z = mean depth, m The volatilization rate coefficient (k , hr~ ) is determined by ky = Ka x k where k is obtained from literature values or computed as above (V&w/Do)• The rate should be corrected for temperature (k .) even though temperature has only a relatively small effect: k = k x 1.024 vt v (T-20) (V-56) 5.6.1.4 Hydrolysis Not all compounds hydrolyze and those that do can be divided into three groups: acid catalyzed, neutral, and base catalyzed reactants. A pseudo first-order hydrolysis constant (k ) is estimated for the hydrolysis of the compound: d (V-57) The rate constant (k ) is pH dependent and varies as discussed in Chapter 2. The typical pH of the lake for the appropriate season should be obtained for the necessary calculations. Generally, the pH is a common measurement and is available for most lakes. If not, pH values for most open lakes lie between 6-9 and can be estimated based on the following empirical values based on Hutchinson, (1957): Hardness (or Alkalinity) pH acid lakes neutral lakes hard water lakes eutrophic and alkaline lakes <25 25 - 75 75 - 200 0 - 300 6 - 6.5 6.5 - 7.5 7.5 - 8.5 8.0 - 10.0 135 ------- Median values on a range of values can be used to evaluate the significance of hydrolysis as a factor affecting the fate of compounds. 5.6.1.5 Photolysis Generally, photolysis is a reaction between ultraviolet light (UV, 260 to 380 nm is most important) and photosensitive chemicals. Not all compounds are subject to photolysis nor does UV light penetrate significantly in turbid lakes. In the absence of turbidity data, light transmission can be estimated by seasonally averaged Secchi disk readings according to the following equation: In (ISD/Io) = -ke(SD) * In 0.1 = -2.3 ke = 2.3/SD where ke is the extinction coefficient and SD is the Secchi depth in meters. (ISD/Io = 0.1) is the relative intensity based on Hutchinson (1957). Photolysis for appropriate chemicals (discussed in detail in Chapter 2) depends on a first order rate constant (k ) incorporating environmental variables (solar iradiance, lo) and chemical variables (quantum yield, 4>, and absorbance, E). Turbidity effects are included as estimated as above since turbidity data are generally not available. These values are incorporated into the rate constant and the concentration reduced as follows (details described in Chapter 2): 31 = - V (v-58> where kr = f (lo, cf>, E, ke, Z) and ko - kr KP - ke-Z 136 ------- -9 o Do = diffusivity of oxygen in water (2.1 x 10 m2/sec, 20 C) mw = pollutant molecular weight W = wind speed, m/sec Z = mean depth, m The volatilization rate coefficient (kv> hr" ) is determined by ky = Ka x k where k is obtained from literature values or computed as above (Vfjw/Do). The rate should be corrected for temperature (k .) even though temperature has only a relatively small effect: k = k x 1.024 vt v (T-20) (V-56) 5.6.1.4 Hydrolysis Not all compounds hydrolyze and those that do can be divided into three groups: acid catalyzed, neutral, and base catalyzed reactants. A pseudo first-order hydrolysis constant (k ) is estimated for the hydrolysis of the compound: dt (V-57) The rate constant (k ) is pH dependent and varies as discussed in Chapter 2. The typical pH of the lake for the appropriate season should be obtained for the necessary calculations. Generally, the pH is a common measurement and is available for most lakes. If not, pH values for most open lakes lie between 6-9 and can be estimated based on the following empirical values based on Hutchinson, (1957): acid lakes neutral lakes hard water lakes eutrophic and alkaline lakes Hardness (or A1kalinity) pH <25 6 - 6.5 25 - 75 6.5 - 7.5 75 - 200 7.5 - 8.5 0 - 300 8.0 - 10.0 135 ------- Median values on a range of values can be used to evaluate the significance of hydrolysis as a factor affecting the fate of compounds. 5.6.1.5 Photolysis Generally, photolysis is a reaction between ultraviolet light (UV, 260 to 380 nm is most important) and photosensitive chemicals. Not all compounds are subject to photolysis nor does UV light penetrate significantly in turbid lakes. In the absence of turbidity data, light transmission can be estimated by seasonally averaged Secchi disk readings according to the following equation: In (ISD/Io) = -ke(SD) * In 0.1 - -2.3 ke = 2.3/SD where ke is the extinction coefficient and SD is the Secchi depth in meters. (ISD/Io = 0.1) is the relative intensity based on Hutchinson (1957). Photolysis for appropriate chemicals (discussed in detail in Chapter 2) depends on a first order rate constant (k ) incorporating environmental variables (solar iradiance, lo) and chemical variables (quantum yield, , and absorbance, E). Turbidity effects are included as estimated as above since turbidity data are generally not available. These values are incorporated into the rate constant and the concentration reduced as follows (details described in Chapter 2): dt where kr = f (lo, cj>, E, ke, Z) and ke-Z • - kc 136 ------- Do = diffusivity of oxygen in water (2.1 x 10" m2/sec, 20 C) mw = pollutant molecular weight W = wind speed, m/sec Z = mean depth, m The volatilization rate coefficient (k , hr" ) is determined by ky = Ka x k where k is obtained from literature values or computed as above (vt)w/Do). The rate should be corrected for temperature (k ,) even though temperature has only a relatively small effect: k = k x 1.024 vt v (T-20) (V-56) 5.6.1.4 Hydrolysis Not all compounds hydrolyze and those that do can be divided into three groups: acid catalyzed, neutral, and base catalyzed reactants. A pseudo first-order hydrolysis constant (k ) is estimated for the hydrolysis of the compound: dC dt (V-57) The rate constant (k ) is pH dependent and varies as discussed in Chapter 2. The typical pH of the lake for the appropriate season should be obtained for the necessary calculations. Generally, the pH is a common measurement and is available for most lakes. If not, pH values for most open lakes lie between 6-9 and can be estimated based on the following empirical values based on Hutchinson, (1957): Hardness (or Alkalinity) pH acid lakes neutral lakes hard water lakes eutrophic and alkaline lakes <25 25 - 75 75 - 200 0 - 300 6 - 6.5 6.5 - 7.5 7.5 - 8.5 8.0 - 10.0 135 ------- Median values on a range of values can be used to evaluate the significance of hydrolysis as a factor affecting the fate of compounds. 5.6.1.5 Photolysis Generally, photolysis is a reaction between ultraviolet light (UV, 260 to 380 nm is most important) and photosensitive chemicals. Not all compounds are subject to photolysis nor does UV light penetrate significantly in turbid lakes. In the absence of turbidity data, light transmission can be estimated by seasonally averaged Secchi disk readings according to the following equation: In (ISD/Io) = -ke(SD) * In 0.1 = -2.3 ke = 2.3/SD where ke is the extinction coefficient and SD is the Secchi depth in meters. (ISD/Io = 0.1) is the relative intensity based on Hutchinson (1957). Photolysis for appropriate chemicals (discussed in detail in Chapter 2) depends on a first order rate constant (k ) incorporating environmental P variables (solar iradiance, lo) and chemical variables (quantum yield, 4>, and absorbance, E). Turbidity effects are included as estimated as above since turbidity data are generally not available. These values are incorporated into the rate constant and the concentration reduced as follows (details described in Chapter 2): 4r = - k C (V-58) dt p where kr = f (lo, 4>, E, ke, Z) and ke-Z 136 ------- -9 o Do = diffusivity of oxygen in water (2.1 x 10" m2/sec, 20 C) mw = pollutant molecular weight W = wind speed, m/sec Z = mean depth, m The volatilization rate coefficient (k , hr" ) is determined by ky = Ka x k where k is obtained from literature values or computed as above (Vbw/Do). The rate should be corrected for temperature (k ,) even though temperature has only a relatively small effect: k = k x 1.024 vt v (T-20) (V-56) 5.6.1.4 Hydrolysis Not all compounds hydrolyze and those that do can be divided into three groups: acid catalyzed, neutral, and base catalyzed reactants. A pseudo first-order hydrolysis constant (k ) is estimated for the hydrolysis of the compound: _dC_ dt (V-57) The rate constant (k ) is pH dependent and varies as discussed in Chapter 2. The typical pH of the lake for the appropriate season should be obtained for the necessary calculations. Generally, the pH is a common measurement and is available for most lakes. If not, pH values for most open lakes lie between 6-9 and can be estimated based on the following empirical values based on Hutchinson, (1957): Hardness (or Alkalinity) pH acid lakes neutral lakes hard water lakes eutrophic and alkaline lakes <25 25 - 75 75 - 200 0 - 300 6 - 6.5 6.5 - 7.5 7.5 - 8.5 8.0 - 10.0 135 ------- Median values on a range of values can be used to evaluate the significance of hydrolysis as a factor affecting the fate of compounds. 5.6.1.5 Photolysis Generally, photolysis is a reaction between ultraviolet light (UV, 260 to 380 nm is most important) and photosensitive chemicals. Not all compounds are subject to photolysis nor does UV light penetrate significantly in turbid lakes. In the absence of turbidity data, light transmission can be estimated by seasonally averaged Secchi disk readings according to the following equation: In (ISD/Io) = -ke(SD) * In 0.1 = -2.3 ke = 2.3/SD where ke is the extinction coefficient and SD is the Secchi depth in meters. (ISD/Io = 0.1) is the relative intensity based on Hutchinson (1957). Photolysis for appropriate chemicals (discussed in detail in Chapter 2) depends on a first order rate constant (k ) incorporating environmental variables (solar iradiance, lo) and chemical variables (quantum yield, $, and absorbance, E). Turbidity effects are included as estimated as above since turbidity data are generally not available. These values are incorporated into the rate constant and the concentration reduced as follows (details described in Chapter 2): 4r = - k C (V-58) at p where kr = f (lo,$, E, ke, Z) and kr kp = ke-Z 136 ------- where k is the photolysis rate constant uncorrected for depth and turbidity of the lake. Depth (Z) is generally applied only to the photic zone and mean depth (7) is an appropriate measure since it approximates the mixed depth and the photic zone. 5.6.1.6 Biocqncentration Bioconcentration is a complex subject that depends on many variables. The simplest approach has been developed for organic compounds using the octanol-water coefficient (kow) to calculate tissue concentrations (Y): Y = BCF x C, g/kg fresh weight of fish flesh. (V-59) where BCF = Bioconcentration factor and log BCF = 0.75 log kow - 0.23, (The coefficients for the equation (0.75, - 0.23) are median estimates obtained from correlation equations and are default values for occasions where no other data are available.) 5.6.2 Guide 1jjT_es_f_g.r Toxics Screening Generally metals do not biodegrade nor volatilize. However, pH, hardness, alkalinity and other ions are very important and can cause their removal by precipitation. The conservative approach is taken here and metals are calculated without removal (K = 0). Organics may have variable sorption, volatilization, and biodegradation rates. If data are available in the literature, these should be used. Otherwise, a conservative approach should be used and calculations made without removal (K = 0). For chlorinated (and other halogens) compounds or refractory compounds, biodegradation should be assumed to be zero. 137 ------- EXAMPLE V-16 Estimating Trichloroethylene and Pyrene Concentrations in an Impoundment An impoundment with a single tributary is located in a windy valley. The following conditions are known for E.G. Lake: Mean tributary flow rate = 3.6 x 101* m3 /hour Total volume = 1.1 x 108 m3 Mean depth = 11 m Tributary average sediment load = 200 mg/1 Sediment average organic carbon content = .05 Inlet average pyrene concentration = 50 ug/1 Inlet average trichloroethylene concentration = 100 ug/1 Lake average phosphorus concentration = 50 ug/1 Mean water temperature = 15°C Mean wind speed = 6 m/sec (35 mph) Secchi depth = 1 m Determine the steady state concentration of pyrene and trichloroethylene in _. k\ the lake, assuming V max for the sediment (mostly clay) is 3.2 x 10 feet/second. The trapping efficiency is obtained from Figure V-33. Other data Pyrene Trichloroethylene kow 148000 190 B IxlO"4 k - 0.45xKa v The processes of photolysis and hydrolysis can be neglected because turbidity prevents photolysis (SD = 1 meter) and these compounds have negligible hydrolysis (see Chapter 2). We use the summary equation (V-47) for the analysis: C - C1n/(l + TW-K) 138 ------- The hydraulic residence time of E.G. Lake is: T - 1.1 x 108 m3/(3.6 x lOTnVhr) = 3048 hours = 127 days = .349 year = 1.1 x 105 seconds Sedimentation First, the suspended sediment concentration in E.G. Lake must be estimated. The trapping efficiency of the impoundment is estimated from Figure V-34. Data: log 10 V max = 5 x 10"6 fps -5.30 T = 1.1 x 106 sec 6.04 D1 = 11 m = 36.1 ft 1.56 A value of 101-95 is obtained which yields P = 90 = 0.9 In the inflowing stream, the toxicants are assumed to be at equilibrium with the organic matter. Thus, S = OC x So - .05 x 200 x 10"6 = 1 x 10"5 kg/1 Therefore, for pyrene K = 0.63 x 148000 x 0.05 = 4660 P + 4660 x 1 x 10"5) - 0.955 139 ------- IO''-1- 10 -&:'. \c-='-i- ::\ IO-^TA 10 -3. 10 0 L To) L 10 3llo-6 St/Sj "\ 0- 4No \ X \N N V : Settling velocity in feet/ second T : Hydraulic residence time in seconds D': Flowing layer depth S : Mass of sediment trapped S.: Mass of sediment entering impound.r:ent L : Pivot axis D .699- = 50 10 I_L FIGURE V - 54 NCXCGRAPH FOR ESTIMATING SEDIMENT TRAP EFFICIENCY 140 ------- - = 0.955 x 4660 x 1 x 10"5 = 0.044 and SED - a x D x K P D = P x S x Q/V D = 0.9 x 200 x 10'6 x - hours -8 D = 5.91 x 10 hour SED = .955 x 5.91 x 10"8 x 4660 SED = 2.63 x 10"4 hr"1 For tr ich• 1oroethylene K = .63 x 190 x 1 x .05 = 6 P 1 + 6 x 1 x 10 ) = 1 = 1 x 6 x 1 x 10"5 = 6 x 10"5 = 0 and SED = 1 x 5.91 x 10 x 6 SED = 3.54 x 10"7 hr"1 B i_qd e q radati q_n Assume that the presence of trichloroethylene does not affect the biodearadation of pyrene. Trichloroethylene does not biodegrade. The 141 ------- temperature corrected and nutrient limited rate constant for microbial decay of pyrene are: Bo = 1. x 10"4 hr"1 B = .0277 x 50/ (1 + .0277 x 50) = .58 8(15) = .58x 1. x 10"4x 1.072 (15 = 4.1 x 10"5 hr"1 Volatilization The reaeration coefficient for E.G. Lake will be estimated for trichloroethylene only, because pyrene does not volatilize: Kal = 2.1 x 10"9 / (200 - 60 x 6^ 10~6 = 3.96 x 10"5 m/sec = .143 m/hr Ka = (.143 m/hr) / 11 m = .013 hr"1 For trichloroethylene (TCE): kv = [MW(TCE)/MW(02)f2 • Ka = .45 x .013 = .0058 hr'1 When adjusted for temperature: (15"20) "1 kv = . 0058 x 1.024 - .0052 hr 142 ------- Volatilization for pyrene may be neglected. Pollutant Mass Balance The overall decay rate constants are: K = SED + B + k Pyrene: K = 2.63 x 10"4 + 4.1 x 10"5 = .000304 hr"1 Trichloroethylene: K = 3.54 x 10" + 0 + 0.0051 = .0052 hr"1 Using the steady state equation: v C = Cin/(l+TwK) For Pyrene C - 50 yg/1 / ( 1 + 3048 hr x .000304 hr'1) C = 27 yg/1 Note: WQC for human health is 0.0028 yg/1 at 10"6 Risk (FR: 11/28/80 p. 79339). For Trichloroethylene C = 100 yg/1 / (1 + 3048 hr x .0052 hr"1) = 5.9 yg/1 Note: WQC for human health is 2.7 yg/1 at 10"6 Risk (FR: 11/28/80 p. 79341) 143 ------- Tissue burdens (Y) can be calculated: Y = BCF x C where log BCF = .75 log kow - 0.23 For Pyrene Y = 4330 x 27 = 120000 yg/kg fish flesh For Tri ch1oroethy1ene Y = 30 x 6 = 180 yg/kg fish flesh Comments Several conclusions are apparent from this analysis t Certain processes dominate the overall fate for a specific toxic chemical so that, practically speaking, errors in estimating coefficients are negligible except for the important processes. After identifying the important processes, the coefficients can be varied to determine the range of concentrations. For example, sedimentation of trichloroethylene can be ignored; however, volatilization should be studied. i The more stringent Water Quality Criteria are for toxicants that have significant bioconcentration; e.g. compare pyrene to trichloroethylene. • Volatilization of trichloroethylene would be investigated in detail since this process might not be significant in this lake because of its depth. Also, the physical properties are important; e.g. trichloroethylene has a specific gravity of 144 ------- about 1.5. Thus, it may accumulate on the bottom of the reservoir and remain there unless it is completely dispersed, • Based on this analysis, sources of pyrene would be assessed first, then trichloroethylene. • What other observations can you draw from this analysis? -END OF EXAMPLE V-16 145 ------- 5-7 ^iJCATIp_N OF METHODS AND EXAMPLE PROBLEM This chapter has presented several approaches to evaluation of five impoundment problem areas. These are thermal stratification, sediment accumulation, eutrophication, hypo!imnion DO/BOD, and toxic chemicals. Figure V-35 shows how the different approaches are linked together with their data needs. In studying any or all of the potential problem areas in an impoundment, the user should first define the potential problems as clearly as he can. Often the nature of a problem will change entirely when its various facets are carefully described and examined en masse. Once the decision is made that an aspect of impoundment water quality should be evaluated and the problem is clearly stated, the user should examine available solution techniques presented both in this document and elsewhere. The examination should address the questions of applicability, degree of accuracy, and need for data. The user will generally know what funds are available for data collection as well as the likelihood of procuring the needed data from previously developed bases. Also, the decision concerning needed accuracy rests with the user, and he should make decisions based upon the way in which his results will be used. Once appropriate methods have been selected, the next task is to set down the data and to manipulate it according to computational requirements. Data are best displayed first in tabular form and then plotted in some meaningful way. Careful tabulation of data and graphing can themselves sometimes provide a solution to a problem, negating need for further analysis. To illustrate these steps, a comprehensive application to a river basin system was performed in this section. .7.1 THE OCCOQUAN RESERVOIR The Occoquan River basin in Virginia was used to demonstrate the screening approach. A basin map is shown in Figure V-36. Because the Occoquan Reservoir is a public drinking water supply downstream from metropolitan areas, v/ater quality data were available to compare to the screening method's outputs. 146 ------- PROCEDURES APPLIED INPUT DAT* FOR RESERVOIRS AND LAKES VOLUME, AREA, MAX DEPTH INFLCH(S) - HIGH, LOU, AND AVERAGE CONDITIONS HI 110 SHIELDING* MEAN WIND VELOCITY* NEAREST CITY* PREDICT SEDIMENT FILLING OF RESERVOIR ^ ' PREDICT EUTROPH1CATION LEVEL ^ P- <„ AND STRATIFICATION SEDIMENT TRAPPING EFFICIENCY t, I * J \ r SEDIMENT LOADS (MEASURED CALCULATED) SEDIMENT DELIVERY RATIO* SEDIMENT TYPE AND PARTICLE SIZE* NUTRIENT LOADS (MEASURED OR CALCULATED) SETTLING VELOCITY* BOD CECAY RATE* BENTHIC OXYGEN CONSUMPTION RATE* TRIBUTARY BOD LOAD SATURATION DO* TOXICANT TYPE SEDIMENTATION RATE REAERATION RATE ACATiON RATE BlOACCUMULATION OBTAINED FROM SCREENING MANUAL. FIGURE V-35 GENERALIZED SCHEMATIC OF LAKE COMPUTATIONS 147 ------- Dulles Airport PRINC WILLIAM COUNTY 0 12345 ccoouan Dam FIGURE V-36 THE OCCOQUAN RIVER BASIN 148 ------- 5.7.2 Stratification Occoquan Reservoir is about 32 km southwest of Washington, D.C. and has the following morphometric characteristics: Volume, m3 = 3.71 x 107 Surface area, m2 = 7.01 x 105 Maximum depth, m = 7.1 (Occoquan Dam) Mean depth, m = 5.29 Based upon the above geometry and the thermal plots, determine whether the lake will stratify, the thickness of the epilimnion and the hypolimnion, the depth to the thermocline, and the interval and starting and ending date of stratification. Also note the temperature of the hypolimnion at the onset of stratification. Predicting the extent of shielding from the wind requires use of topographic maps. The reservoir is situated among hills that rise 25 meters or more above the lake surface within 200 meters of the shore. The relief provides little access for wind to the lake surface. Average annual wind speeds are 15.6 km/hr in Washington, D.C. and 12.6 km/hr in Richmond, VA. Inflow comes essentially from two creeks, the Occoquan River and Bull Run River (Figure V-36). First, determine needed information and then do metric/English conversions as necessary. The first step in assessing impoundment water quality is to determine whether the impoundment thermally stratifies. This requires knowledge of local climate, impoundment geometry, and inflow rates. Using this information, thermal plots likely to reflect conditions in the prototype are selected from Appendix D. 149 ------- For the thermal plots to realistically describe the thermal behavior of the prototype, the plots must be selected for a locale climatically similar to that of the area under study. Because the Occoquan Reservoir is within 32 kilometers of Washington, D.C., the Washington thermal plots (Appendix D) should best reflect the climatic conditions of the Occoquan watershed. The second criterion for selecting a set of thermal plots is the degree of wind stress on the reservoir. This is determined by evaluating the amount of protection from wind afforded the reservoir and estimating the intensity of the local winds. Table V-2 shows annual wind speed frequency distribution for Washington, D.C. and Richmond, Virginia. The data suggest that winds in the Occoquan area are of moderate intensity. Predicting the extent of shielding from the wind requires use of topographic maps. The reservoir is situated among hills that rise 25 meters or more above the lake surface within 200 meters of the shore. The relief provides little access for wind to the lake surface. The combinatiuon of shielding and moderate winds implies that low wind stress plots are appropriate. The geometry of the reservoir is the third criterion used in the selection of thermal plots. Geometric data for the Occoquan Reservoir are summarized in the problem. The volume, surface area, and maximum depth are all nearly midway between the parameter values used in the 40-foot and 75-foot maximum-depth plots. However, the mean depth is much closer to the mean depth of the 40-foot plot. The mean depth represents the ratio of the volume of the impoundment to its surface area. Because the volume and surface area are proportional to the thermal capacity and heat transfer rates respectively, the mean depth should be useful in characterizing the thermal response of the impoundment. It follows that the 40-foot thermal profiles should match the temperatures in the Occoquan Reservoir more closely than the 75-foot profiles. However, it is desirable to use both plots in order to bracket the actual temperature. 150 ------- Flow data provide the final information needed to determine which thermal plots should be used. The inflow from the two tributaries adds up to be 20.09 mVsec. The hydraulic residence time can be estimated by using the expression , V . 3.71 x 10' .' 20.09 x 86400 - . 21-4 days Since the residence time is midway between the thermal plot parameter values of 10 and 30 days, both should be used to bracket the mean hydraulic residence time in the prototype. It should be noted that these flow estimates do not include runoff from the area immediately around the lake. However, the upstream Occoquan watershed is large enough relative to the immediate runoff and direct precipitation to justify the assumption that the contribution of the immediate area is not significant. The likelihood that the Occoquan Reservoir thermally stratifies can now be evaluated. For a hydraulic residence time of ten days, the thermal plots show that stratification is not likely for maximum depths of 40 to 75 feet. In the case of a 30-day hydraulic residence time, the profiles suggest that the reservoir develops a thermal gradient between 1°C m and 3°C nf * for either value of maximum impoundment depth. The 40-foot plots (Figure V-37) indicate stratification occurs from May to August at 5-7 meters depth. However, the 75-foot plots predict that the impoundment will have a thermal gradient greater than 1°C m"1 only at depths greater than 17 meters. Since the Occoquan Reservoir is 17.1 meters deep at the deepest station, this suggests that the impoundment does not stratify. The mean hydraulic residence time can be computed using either the average annual flow rate or the flow rate just prior to stratification. In order to use the latter method, the flow rate during the months of March and April should be computed. The flow rate for this period, 25.4 m3 sec"1, reduces the hydraulic retention time to 17 days. Since the model predicts no stratification for a ten-day residence time, the judgment as to whether stratification occurs becomes difficult. 151 ------- 4 • 4 • CL UJ o Q_ UJ ° Q- UJ o a. U-l o 0 10 20 3D TEnr. c t? X t— a. 17 x t— O_ LLJ O 1? 0 10 20 3D TEnr. C BUt 0 10 20 30 TEnr. c 0 10 20 30 TEMP. C o 10 ;o 30 TFf.P. C 12 0 10 20 30 TEMP. C DEC o 10 ^o 30 TEMP. C 0- LU o 0 10 20 30 TEMP. C 12 10 20 30 TEMP. C OC1 0 10 20 33 TEMP. C WASHINGTON, B.C. 40 ' INI T IRL MRXIMUM DEPTH 30 DOT HTDR- RES. TIME MINIMUM MIXING FIGURE V-37 THERMAL PROFILE PLOTS FOR OCCOQUAN RESERVOIR 152 ------- Because lower flows occur during the summer, the 30-day residence time, 40 foot depth and minimum mixing should be used. In borderline cases such as this, the reservoir will almost certainly stratify during some part of the summer. The temperatures predicted by the thermal plots match those actually measured in the reservoir quite closely. A comparison of predicted and observed monthly mean temperatures (1974-1976) in both the epilimnion and hypolimnion can be made using observed data (Table V-17) and the plot of the 40 foot, 30 day residence time, minimum mixing (Figure V-37). The difference between the two epilimnion temperatures averages 1.0°C and varies between 0.2 and 1.8 C. The difference in the hypolimnion temperatures averages 1.0°C and ranges from 0.2 to 2.7°C. The close agreement of the predicted and observed impoundment temperatures probably results from the relatively long hydraulic residence times observed in two of the three years on which the averages are based. In 1974, 1975, and 1976, the mean hydraulic residence times were 31, 18, and 25 days, respectively. The 30-day thermal plots should predict results relatively close to the two low-flow years. The differences expected for 1975 would be less pronounced when averaged with the other two. In conclusion, Occoquan Reservoir does apparently stratify, the depth to the thermocline or the epilimnion approximates the mean depth (5.29), the hypolimnion has a depth of 11.8 m (17.1-5.3), and the interval of stratification approximates May 1 to mid September or 138 days. The hypolimnetic temperature is about 11 degrees C, typically. 5.7.3 Sedimentation To evaluate potential sedimentation problems, Appendix F is examined to see if any data exist on the upstream reservoir (Jackson) or Occoquan Reservoir (Figure V-36). Some data exist for Jackson but not for Occoquan Reservoir (Figure V-38 taken from Appendix F). Thus, we can determine the trapping of sediment in Jackson Reservoir but trapping must be calculated 153 ------- TABLE V-17 COMPARISON OF MODELED THERMAL PROFILES TO OBSERVED TEMPERATURES IN OCCOQUAN RESERVOIR Month March April May June July August September October November December Hean EpU imnion 40-foot Plot (°C)J; 7 13.5 19 24 26 26 22 17 11 7 Temp. Observed 8.4 12.6 20.5 24.8 26.6 26.5 23.8 17.2 12.2 6.2 Hean llypol imnion 40-foot Plot ("C)b) 6 10 15 18 20 21 20 16 10 7 Temp. Observedc 6.3 9.2 14.4 . 17.2 21.2 23.7 20.2 15.8 11.6 5.8 Epil Imnion Depth (m) 40-foot P)ott; -- -- 4.5 5.0 6.5 7 -- -- -- -- *J(lean temperatures In ep1l1mn1on from thermal plots with T » 30 days and a maximum depth of 40 feet. temperatures 1n therrrocline and hypolimnion from thermal plots with T • 30 days and a maximum depth of 40 feet. c>Means of observed temperatures 1n "upper" and "lower" layers of Occoquan Reservoir for 1974-1976, at Sandy Run. Source: northern Virginia Planning District Commission, January , 1979. ------- DATA SHEET NUMBER | RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL [ NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG ANN INFLOW (ACRE-FT. PER AUHfc-Kll SPECIFIC WEIGHT (DRY) LB. PER CU. FT.) AVG. ANN SEDIMENT ACCUMULATION PEB S(J. MI. OF NET DB. AREA FOR PERIOD SHOWN AC.-FT. | TONS AGENCY SUPPLYING DATA POIOMC, UPFAIUIIKXX, TOM, UK JAWS HID BASIK5 tn tn 5-3 5-3 5-4b 5-6 5-7b 5-8 5-10 5-13 5-13 6-1 6-3 6-3 6-4 n hit Tt*"rt *" d 5ta t ** •o ion Triadelphia L. (Brignton D. )- rt .° . *° '*rt r South Rl»«r, Site 26 > l * ** * Laki Ap^ic — — — — Frankllnton- Oreensboro (L. Brandt) High Point to If. h. Br, AncoovtU River- t rib. o ndlui r rt 'rv.» .IfKlMrl "" rto _ _ ^° 0. PatttJtent RiYfP- Inch B v ^ ««C Ll . t « aturent allU lanoy Craoic F e oj r »dged in 1937-1939. Oroooee, T*. Silw Spring, Md. hi t »M reen el , do Sta ton T . ' ^ Hk 7 *' fiV-f«tit° nVt d ' do ° •1 fftnn >M 5"*"* W^n.rtoro, V. *' CHCW4N, ROANDKE, TAfi, High ftiint, N. C 33.21 27.0 337 •1.4 60 105.0 132.8 2.7 1.8» NEUSE, AND CA! 4.0 1.13 62.8 " & 33.07 25 336.4 to.y 59.6 104.44 50.14 2.7 1.S5 >E F£AH Rl 4.0 1.12 73.4 62.3 Kevls.d 1 9 .cr»-r. F*. 1938 *««. 1957 F*. 1907 F*. 1938 */ 1930 lUr. 1938 Julj 1936 F*. 1938 A««. 1957 Jmm 1968 DM. 1925 J*Q. 1940 Jan* 1957 July 1930 Au». 1937 Jui. 1942 Oct. 1950 S«pt. 1958 Aug. 1964 S^rt. 1913 Apr. 1940 M.r. 1932 Apr. 1940 ««r. 1952 Kir. 1956 ttor. 1954 Aug. 1964 H*J 1956 Hoi. 1970 S.pt. 1966 Aug. 1968 Aug. 1969 VER BASINS — 1925 June 1941 J«n. 1925 *J 1938 F«b. 1923 Aug. 1934 Jui. 1928 Aug. 1934 Apr. 1939 968. •t c*lned br dr< 23.1 17.5 31 1.6 19.5 14 17.5 7.2 8.3 7.9 5.9 26.6 8.1 4.0 10.4 14.5 1.9 1.0 16 13.3 11.5 ~6.5 3.75 jA*762 i'e6o 1.72J 181 95 1% 186 151 UA47 373 350 4,500 4,158 20J089 19,633 19,045 3,129 3,004 7,312 7,394 20,300 20,020 21,390 20,789 6X0.4 607.0 196.97 170.99 163.72 106 94 34.7 27.3 2,870 2,610 4,354 4,135 4,038 .134 .161 •.312 •.596 •.240 .234 _ .327 .324 .317 .308 .172 .169 .28 .28 .140 .122 .117 — •60 •60 •60 •60 •60 •60 •50 •50 61.1 •60 67 •60 •60 •60 67 •60 50.6 .257 .728 .134 .408 7.91 10 2.27 2 1.52 1 .034 .053 .141 .20 .72 1.25 1 U/.090 .036 ~.643 1.15 1 .087 12/7.3916/11 3.93 5 .19 .509 .308 .541 .416 336 950 533 ,337 ,970 .945 184 218 784 ,663 r'a ,678 110 ,278 .133 743 402 596 458 SCS SC3 SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS scs s:s SCS 2/ Partial vurv«r covering e«gn«nta 1-11 In 3ton«y Brook Am Onlj. \jj Net Mdlaent contributing area was 299.4 mq. ml. until 1933 "ban Prtttyboy Daa M*B oomplet*d. this ar*a was uo«d In tha I9iJ calculations. */ Rr*ia»d aft«r 1961 flttrr«y. 6/ Conaarwtlon or »»din«nt pool only. 2/ Mot datamlnod - aaauned equal to that d»t*rmin«d in 1963. fl/ 6a*«d on origin*! •pillvsj oreat alrratlon 20^ f««t a. B. 1. O/ tafu*4 nn (tpillwi* rront •l«ratl'>n 210 fo«t n. ". 1. and natlnwtM eamolty nf 2,WO acr^-f**! Revieed due to movable control gat^s. Koon Lake, upstream, was built In 1932. Baaerl on total sediment in both Gordon Lake and Koon Lake. Does not include U.JU acre-feet dredged. Include* U.3U acre-feet dredge4 In early spring I960. FIGURE V-38 SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 ------- for the Occoquan. To refine the analysis, calculations on Jackson Reservoir will also be made and the results calibrated. To apply the Stokes1 law approach to a reservoir, we need to know the loading first. The necessary sediment loading estimates for the tributaries were provided by the methods in Chapter 3 and are listed in Table V-18 (Dean e_t aj_., 1980) Before they are used in further computations, a delivery factor must be applied to these values. This factor (the sediment delivery ratio or SDR) accounts for the fact that not all the sediment removed from the land surface actually reaches the watershed outlet. Nonpoint loads from urban sources are presumed to enter the reservoir through Bull Run River since most of the urbanized portion of the watershed lies in this sub-basin. Computing the annual sediment load into Occoquan Reservoir is complicated by the presence of Lake Jackson immediately upstream from the reservoir. The trap efficiency must be computed for Lake Jackson as well in order to determine the amount of sediment entering the Occoquan Reservoir from Lake Jackson. The steps involved are to compute the sediment delivered (Table V-19), the size range, the fraction trapped for each size range and the total amount trapped. A table has been devised to simplify these steps (Table V-20). Soil types provide an indication of the particle sizes in the basin under study. Soils in the Occoquan basin are predominately silt loams. Particle size data on the principal variety, Penn silt loam, are given in Table V-21. These data and all calculations are transcribed into Table V-22. Some effort can be conserved by first calculating the smallest particle size that will be completely trapped in the impoundment. To do so, P, the trap efficiency, must first be computed. Because both reservoirs are long and narrow and have relatively small residence times, the flow will be assumed to approximate vertically mixed plug flow (Case Bl). In this case, P is found from the expression: 156 ------- TABLE V-18 ANNUAL SEDIMENT AND POLLUTANT LOADS IN OCCOQUAN WATERSHED IN METRIC TONS PER en Type of Load Total Nitrogen Available Nitrogen Total Phosphorus Available Phosphorus BOD,. D Rainfall Nitrogen 'Kettle Run 46,898 164.46 16.45 39.01 2.18 328.92 0.72 Cedar Run 396,312 1,457.42 145.74 341.95 14.95 2,925.63 5.50 Broad Run 142,241 518.91 51.89 114.22 5.57 1,042.45 2.00 Bull Run 232,103 789.24 78.92 202.71 12.50 1,578.47 3.92 Occoquan River 139,685 469.46 46.05 119.42 8.43 925.85 2.48 Urban Runoff 12,699 12.88 5.38 2.59 1.27 77 .47 - a) Estimates provided by Midwest Research Institutes Nonpoint Source Calculator. These values have not yet had a sediment delivery ratio (SDR) applied to them. We will use 0.1 and 0.2 as lower and upper bounds. The SDR does not apply to rainfall nitrogen. Note: A large number of significant figures have been retained in these values to ensure the accuracy of later calculations. ------- TABLE V-19 SEDIMENT TRIBUTARIES TO LAKE JACKSON KETTLE RUN CEDAR RUN BROAD RUN TOTAL LOADED INTO LAKE JACKSON, 1,000 KG/YEAR AVAILABLE SEDIMENT 46,898 396,312 142,241 SEDIMENT LAKE CASE I (SDR=0,1) 4,690 39,630 14,220 58,540 DELIVERED To JACKSON CASE II (SDR=0,2) 9,380 79,260 28,440 117,080 158 ------- TABLE V-20 CALCULATION FORMAT FOR DETERMINING SEDIMENT ACCUMULATION IN RESERVOIRS (NOTE UNITS) Size Fraction Percent Composition Density Absolute Bulk Mean Particle Diameter vmax Fraction Trapped (P) A B Test Case Incoming Sediment • Trapped Sediment en ------- TABLE V-21 PARTICLE SIZES IN PENN SILT LOAM Particle Size * of Particles Smaller Than (imp (By Weight) 4.76 100 2.00 99 0.42 93 0.074 84 0.05 78 0.02 50 0.005 26 0.002 16 160 ------- TABLE V-22 CALCULATION FORMAT FOR DETERMINING SEDIMENT ACCUMULATION IN RESERVOIRS (NOTE UNITS) Size Fraction cin .000514 .00050 .00035 .00020 >. 000518 Percent Composition 0.3 5 5 16 73.7 Example Calculation Density Absolute 2.66 2.66 2.66 2.66 2.66 SDR = C Vol = 2 Vol of (75 yrs Bulk 2.24 2.24 2.24 1.28 2.33 average' .115 4750 m3/ Jackson lifetim Mean Particle Diameter N/A N/A N/A N/A N/A /r Reservoir e) Vpiax m/day 1.90 1.79 0.88 0.29 - Totals Trapped ast per y Fraction Trapped (P) A N/A N/A N/A N/A N/A >a Y* ~~ -. 1 B 1.00 0.94 0.46 0.15 1.00 24750 593000 Test Case I II I II I II I II I II I mtons/y II mtons/y I m3/yr II m3/yr n3/yr _ -, r/ n3 m tc Incoming Sediment 176 352 2927 5854 2927 5854 9366 18732 43144 86288 - 48822 - 97644 21523 43046 'year n/yr Trapped Sediment m3/yr 176 79 352 158 2751 1228 5502 1356 601 2582 1209 1405 1098 2810 2196 43144 19000 86288 37000 ------- max T_w P = D' where D1 = mean flowing layer depth, m. To calculate the smallest particle that is trapped in the impoundment, P is set equal to unity and the above equation is solved for V max V vmax w This expression for V is then substituted into the fall velocity equation max (Stokes1 law), which in turn is solved for d. .4-8 x 1Q6 (DP - DW) d2 = rr %ax " p T The resulting expression is: d» °' y 6 v 4.8 x 10" /D - D ^ • T ^ p w^ w The trap efficiency of Lake Jackson is calculated first. The data required for these calculations are: V = 1.893 x 106 m3 Q = 12.47 m3 sec"1 D = 3.34 m p = 1.11 (Assuming T = 16°C as in Occoquan Reservoir) and Tw=l= 1.893 x 106 m3 .- 1.76 days Q 12.47 m3 • sec • 86400 sec • day"1 The minimum particle size for 100 percent trapping is computed as: d = /3-34m x 1'11 = 5.14 x 10-4 cm V 4.8 x 106 (2.66 - 1.0) • 1.76 162 ------- The amount trapped of each size fraction is computed separately for Case B-l from the equation p _ max Tw D1 For example, for size fraction 0.00035 cm, p . loBm . 0.46 A composite trapping efficiency can be obtained by determining the total percent trapped (48822/58540 = 0.83). The sediment accumulated in Lake Jackson for each size range is determined from the expression: S = P • S \ i where P = trap efficiency S. = sediment load from tributary i S = sediment trapped For the two cases (I, II): St = (0.1, 0.1) x 0.83 [46898 + 132241] metric tons/year = (48822, 97644) metric tons/year. Data obtained from Appendix F of the screening manual show that the estimated rate of sedimentation in Lake Jackson is 56,153 metric tons/year. This indicates that an SDR of 0.115 would be appropriate. Bulk density (g/cc) includes the water that fills pore spaces in sediment that has settled to the bottom and this must be accounted for when determining volume lost due to sedimentation. Bulk density varies with particle size and some approximate values for the size ranges for sand (0.005-0.2 cm), silt (0.0002-0.005 cm), and clay (<0.0002 cm) are as follows: 2.56 for sand, 2.24 for silt and 1.28 for clay. Thus, using an 163 ------- SDR of .115, 24,750 m3 (or 1.3%) of reservoir volume would be lost per year. In comparing to Appendix F data, we find that this value is conservative. The loss of volume was estimated by the SCS to be 47.5 acre feet/year while these calculations show only 20 acre feet/year being lost. The estimated bulk density used by the SCS was 0.93 g/cc and we used a more conservative value. If the SCS figure is used, the volume lost is determined to be 46.4 acre feet/year. Now we compute the sedimentation in Occoquan Reservoir. The minimum particle size that is completely trapped is computed using the following values: D' = 5.29 u = 1.11 (T = 16°C = mean of Table V-17) DW = 2.66 g cm "3 Dw = 1.0 g cm"3 TW = 21.4 days Under stratified conditions, the epilimnion thickness should be used for D'. Since stratification is uncertain in this case and the predicted average hypolimnion thickness, 5.75 m, is greater than the mean depth, the latter value will be used. All particles with diameter, d, such that: rs = V ~4. 1.11 3 x 106 (2.66 - 1.0) • 21.4 will be completely trapped in the Occoquan Reservoir. Because this value is smaller than the smallest size calculated for Lake Jackson (2 x 10 cm), our computations are simple. We assumed that 84 percent of the sediment is totally trapped and the remainder is trapped at an efficiency calculated for particle sizes of 0.0001 cm: 4.8 x 106 (2.66 - 1.) (1 xjgjjJL = I_TI = 0.072 in/day 164 ------- D »•— Tw 0.072 • 21.4 P = ^ = - 5729- The annual sediment trapped is St = P ' Si but corrections for sources and SDR must be made: S = SDR x sediment from each source. i S. = 13390 (Lake Jackson, already corrected for SDR) 0.115 (232103) (Bull Run) + 0.115 (139685) (Occoquan River) + 12699 (Urban Runoff) S. = 68845 metric tons/year Assuming the distribution of particle sizes for all sources are essentially the same and accounting for the fractions (f) of material that are in the two different size ranges: S. = f, Px S. + f2 P2 S. S = (0.84) (1.0)(68845) + (0.16) (0.29) (68845) I* S = 57830 ; 3194 = 61024 metric tons Lr The volume lost is -^"._•• = 65620 m3 /year or 0.2 percent per year of the reservoir volume. 5.7.4 Eutrophication What would be the consequences to eutrophication in Occoquan Reservoir of instituting 90 percent phosphorus removal at the treatment plant? If, in addition to phosphorus removal, nonpoint source (NPS) phosphorus was reduced by 90 percent by instituting urban runoff and erosion control, green belts, and other NPS controls, would an improvement in lake quality occur? 165 ------- Several assumptions concerning pollutants in the Occoquan watershed-reservoir system are necessary in order to calculate the desired annual loads: • The unavailable phosphorus is adsorbed on sediment particles. Therefore, of the unavailable forms coming into Lake Jackson, only the fraction (1 - P [Jackson]) is delivered to the Occoquan Reservoir; Available P gets through Jackson. • All of the phosphorus and nitrogen from the sewage treatment plants (STPs) is in available form; • The output of STPs outside the Bull Run sub-basin is negligible compared to that of the STPs in Bull Run. This is justified by the fact that during the period: under study, the plants in Bull Run had a combined capacity several times larger than the few plants outside the sub-basin. • The problems of eutrophication depend on loading of phosphorus. By applying these assumptions to the nonpoint source data in Tables V-18 and V-23 the total load of each pollutant type may be calculated (Table V-24). The computation for the total annual phosphorus load in Occoquan Reservoir is computed in the following paragraphs. First the quantity of total phosphorus coming into the Occoquan Reservoir through Lake Jackson is calculated by: TP, , = (1 - P ) x [Total P - Available P] + Available P Jackson cjackson The total phosphorus from Broad Run, Cedar Run, and Kettle Run are summed and the available phosphorus loads are subtracted to give the unavailable load. This load is multiplied by the trap efficiency of the lake, P = 0.83, which yields the unavailable load passing through. This value, plus the available load, is an estimate of the total phosphorus entering Occoquan Reservoir from Lake Jackson. This quantity is 103.24 metric tons yr~ (Table V-24). This value is aded to the non-urban, nonpoint source 166 ------- TABLE V-23 SEWAGE TREATMENT PLANT POLLUTANT LOADS IN BULL RUN SUB-BASIN IN METRIC TONS PER Total Nitrogen Total Phosphorus BODr 108.0 11.92 54.80 a; Averages for July 1974 - December 1977 Source: Northern Virginia Planning District Commission, March 1979. 167 ------- TABLE V-24 CALCULATED ANNUAL POLLUTANT LOADS TO OCCOQUAN RESERVOIR Load Source Urban runoff Sewage treatment Rainfall Other Nonpoint Source* TOTAL Nonpoint Source % Point Source % Total N 12.38 103.00 14.62 391.00 526.50 80 20 Metri Ava i 1 . N 5.38 108.00 14.62 39.10 167.10 35 65 c Tons/Year Total P 2.59 11.92 - 48.83 63.34 81 19 Avail .P 1.27 11.92 - 2.65 15.84 25 75 BODs 77.47 54.80 - 802.00 934.27 - 94 6 Used SDR of 0.115. 168 ------- loads from Bull Run and areas adjacent to the Occoquan Reservoir (Table V-18): TPNPNU = 202-71 + I19-42 + 103.24 = 425.37 metric tons yr . This quantity is modified by the sediment delivery ratio. The urban nonpoint loads and STP (Table V-24) loads are added to complete the calculation: TP = (0.115) (425) + 2.59 + 11.92 = 63.3 metric tons yr" . Similarly the SDR was applied to nonpoint sources of nitrogen and BOD5. The results of load calculations are summarized in Table V-24. The calculated annual total phosphorus and nitrogen loads (Table V-24) may be compared with the observed loads listed in Table V-25. The loads observed are 1.5 to 6 times higher than highest calculated loads for nitrogen. Comparison of loadings (kg/ha year) with literature values suggest that Grizzard is most accurate (Likens e_t^ aj_. , 1977). The first method of predicting algal growth is known as the o Vollenweider Relationship. In the graph of total phosphorus load (g m yr ) versus mean depth (m) divided by hydraulic retention time (yrs) (see Figure V-24), areas can be defined that roughly correspond to the nutritional state of the impoundment. For the Occoquan Reservoir, the values of the parameters are: Lp . (63.34) x 10* g/yr „ g^ g m-2 yr-l 7.01 x 106 m2 L- = „ 5-29 m = on m vr-l TW (J.0586 yr ^ m yr According to the Vollenweider Relationship, Occoquan Reservoir is well into the eutrophic region for loading of total phosphorus. Based on these predictions a more in-depth study of the algal productivity seems to be in order. 169 ------- TABLE V-25 OBSERVED ANNUAL POLLUTANT LOADS TO OCCOQUAN RESERVOIR Mean Flow3'1 Rate Total Nitrogen Load Period (m sec~ ) (metric tons year" ) 10/74 7/75 7/76 - 9/75 24.7 805i; - 6/76 24.0 1905C') - 6/77 10.4 4763cj Total Phosphorus Load (metric tons year ) Il0b) 188c; 454c; ^Source: USGS Regional Office, Richmond, Virginia. i;Grizzard et al_., 1977 c;Northern Virginia Planning District Commission, March, 1979. Data gathered by Occoquan Watershed Monitoring Laboratory. ------- Solving for the phosphorus concentration in this reservoir Lp 1 9.04 g m"2 yr""1 P = — Z D+VcF 5.29mi(I7.1+VrTl)yr-1'] ? = 0.0305 g/m3 = 80.5 yg/1 . Calculated and observed pollutant concentrations are listed in Table V-26. The mean summer concentrations of phosphorus and nitrogen are closer to the concentrations calculated than would be expected on the basis of the comparison of annual loads. The ratio of nitrogen to phosphorus concentration in the reservoir can be used to estimate which nutrient will limit the rate of plant growth. For the Occoquan Reservoir, the N:P ratios are 10 to 1 for total N to total P. The calculated nutrient ratios and the N:P ratio of the observed data (11.0) indicates that phosphorus is probably growth limiting. The available data also permits the estimation of the maximal primary production of algae from the Chiaudani and Vighi Curve (Figure V-26). The theoretical phosphorus concentration should be about 0.08 g nf^ according to calculations. The maximal primary production of algae is found from Figure ? 1 V-26 to be about 2500 mgC m day . This level of algal production is roughly the maximum production shown on the curve. Both this result and the Vollenweider Relationship suggest algal growth will contribute significantly to the BOD load in the impoundment. • Effects of 90 percent P removal at treatment plant on TP loading: M = 52.61 m ton/yr q = 90 m yr'1 171 ------- TABLE V-26 CALCULATED AND OBSERVED MEAN ANNUAL POLLUTANT CONCENTRATIONS IN OCCOQUAN RESERVOIR Total L Available Total Nitrogen Nitrogen Phosphorus (9 m 3) (g m 3) (g nf3) Calculated (SDR = 0.115) 0.831 0.264 0.08 Observed Values Mean Max. Min. 0.88 1.50 0.35 0.16 0.24 0.10 0.08 0.12 0.04 a)Assuming no removal processes for nitrogen. b)Averages for April-October between 1973 and 1977. Source: Northern Virginia Planning District Commission, March, 1979. 172 ------- Although improved, we conclude that loading is still too great according to Figure V-24. • Effects of 90 percent STP removal of TP plus 90 percent NFS removal of TP: M = 6.334 m ton/yr . 6.334 x 106 n Qn -2 -1 LP = 7.01xlOb = °-909m y This would move Occoquan Reservoir into the bottom of the mesotrophic range. Lake concentrations of total P would be: p = > / = 66 9 n on P = Tr Although the screening method shows marked improvement in Occoquan eutrophication, 90 percent control of phosphorus NPS would be very expensive. Careful analysis of assumptions made in the screening method and of control alternatives would be necessary before proceeding to map such a control strategy. Moreover, careful study of reservoir TP sources and sinks and of algal productivity would be necessary. The screening method has served to illustrate the feasibility and potential value of such further analysis. 5.7.5 Hypolimnetic DO Depletion Excessive nutrient loading plus inputs of BODs suggest that DO problems in the hypolimnion could result. We will use the data obtained in the first three problems to determine the hypolimnetic DO. These data are summarized below. All rate coefficients listed have already been corrected for temperature. 173 ------- Physical/Biological Area = 7.01 x 106 m2 Volume = 3.71 x 107 m3 Q = 20.09 m3 sec"1 = 1.74 x 10b m' day Depth to thermocline = 5.29 m (average depth) Interval of stratification (May to mid-September) = 138 days BOD loading = 934.27 106g . yr"1 Algal loading = 11800 mgCnf day'1 BOD concentration = 934.27 x 106 g/yr = 0.069 mg/1 3.71 x 10V x 365 days/yr Temperature = 10°C Rates and Input Values M = 0.8 kj = 0.063 day"1 S = 2.67 k = 0.0378 day"1 P = 0.824 gC m"2 day ~l k^ = 0.0019 day"1 D = 5.29 m DO = 11.3 mg/1 TW = 21.4 day t = 138 The simplified model used to predict hypolimnion dissolved oxygen levels assumes that the only substantial dissolved oxygen sinks are water column and benthic deposit BOD (Section 5.5). Additionally, all sources of oxygen, photosynthesis, etc., are neglected in the hypolimnion after the onset of stratification. Thus, the procedure requires that pre-stratification levels of BOD and dissolved oxygen be estimated in order to compute the post-stratification rate of oxygen disappearance. The pre-stratification concentration of water column BOD is determined first. A simple mass balance leads to the following relationship, if steady state conditions are assumed: k a 174 ------- where C = steady state concentration of BOD in water column, mg/1 SS _o _i k = mean rate of BOD loading from all sources g m day a i k = -k - kz - -L b s Tw where k = V /I - mean rate of BOD settling out onto impoundment s s , bottom, day kj = mean rate of decay of water column BOD, day" Q = mean export flow rate, m3 day" V = impoundment volume, m3 V = settling velocity, m day" I = impoundment mean depth, m. The BOD load to the impoundment originates in two principal sources: algal growth and tributary loads. The algal BOD loading rate is computed from the expression: k , . . = SMP/Z a(algae) ' S = stoichiometric conversion from algal biomass as carbon to BOD =2.67 M = proportion of algal biomass expressed as oxygen demand 2 P = algal primary production, g m day Since the Chiaudani and Vighi curve (Figure V-26) gives the maximal algal production, a correction should be made for the actual epilimnion temperature. If the maximal rate occurs at 30 C and the productivity decreases by half for each 15°C decrease in temperature, 175 ------- the algal production can be corrected for temperature using the expression: P = P x 1 047("1""^ C) P(T) P(30) X 1>04/ According to the data in Table 1, the epilimnion temperature during the month prior to stratification is approximately 13°C. Thus: P ------- Ideally these would be determined by using values of the physical properties of the particles and the water in the settling velocity equation, (V-6). Because such data are lacking, a settling velocity of 0.2 m day reported for detritus will be substituted. The reported values lie between 0 and 2 meters day" , with most values close to 0.2 m day"1 (Zison et al_. , 1978). Then, k = 0.2 m day"V5.29 m = .0378 day"1 The second constant comprising k, is the first-order decay rate constant for water column BOD. Reported values of kj. vary widely depending on the degree of waste treatement. Zison e_t aj_. (1978) presents data for rivers, but contains only two values for kx in lakes and estuaries. Both are ki = 0.2 day" . Camp (1968) reports values from 0.01 for slowly metabolized industrial wastes to 0.3 for raw sewage. Because there is considerable sewage discharge into the Occoquan Reservoir, k: may be assumed to be in the upper range of these values, between 0.1 and 0.3 or 0.15 day" . Like the algal production rate, ^ must be corrected for the water temperature. In April, the mean water temperature is about 11 C. Then : k = 0.095 day"1 x 1.047 (n C"20 = 0.063 day"1 Finally, k, is evaluated as follows: k, = -0.0378 day"1 - 0.063 day"1 L. D 21.4 days = -0.148 day"1 Next, ka and kb may be substituted into the following equation to obtain Css. 177 ------- Once the water column BOD concentration is known, the benthic BOD is computed from the expression: k C D _ s ss where k4= mean rate of benthic BOD decay, day'1. Values for the benthic BOD decay rate constant span a greater range than those for water column BOD. Camp (1968), however, reports values of ku very near 0.003 day for a range of benthic depth from 1.42 to 10.2 cm (Table V-10). Assuming this to be a good value, a temperature-corrected value of k4 may be computed at an April hypolimnion temperature of 10°C (Table V-17): k, = 0.003 day'1 x 1.047(10'2°) = 0.0019 day'1 Then, L = 0-Q378 day -1 x 2.72 g m'3 x 5.29 m SS 0.0019 day"1 = 286 g m"2 Prior to stratification the impoundment is assumed to be fully mixed and saturated with oxygen. During April, the hypolimnion temperature is 10°C. Saturated water at this temperature contains 11.3 ppm oxygen (Table V-ll). Finally, the dissolved oxygen level in the hypolimnion may be predicted during the period of stratification. The applicable expressions are: 178 ------- A B C E B AOL = (1.04) [(53.1) (0.231) - (1/53.1)] AOL - 12.74 F E A0c = (1.7) (1) = 1.7 Ot = 11.3 - 12.74 - 1.7 Therefore the hypolimnion is depleted of oxygen at the end of the stratification period (138 days). By selecting different conditions for decay rates and for time of stratification a family of curves was generated that can be compared with actual observations (Figure V-39). As can be seen situations 3 and 4 (BOD decay of 0.3 later corrected for O 1 temperature and a total BOD loading of 0.36 or 0.57 g . m day ) gave a reasonable fit of observed data at the deepest station (Occoquan Dam, 1973). Interpretation of the dissolved oxygen-time data at High Dam in 1970 presented in Figure V-39 is complicated by the introduction of fresh oxygen after the onset of stratification. Although a direct comparison of oxygen depletion times is not possible, the rates of oxygen level follows curve 2 of Figure V-39 very closely, while during the second period of oxygen consumption the oxygen concentrations closely match those of curve 1. Since the reservoir is shallowest at High Dam and the substantially lower than average flow rate in 1970 resulted in strongly stratified conditions, the oxygen depletion rates in this case should be among the highest likely to be observed in the impoundment. Curve 1 represents the fastest decay rates predicted by the model. Thus, the observed oxygen consumption times should be greater than the lower limit predicted by the model in nearly all cases. The above agreement of the observed with the predicted limits for the range of oxygen depletion times in Occoquan Reservoir implies that the typical or average time must also fall within the predicted range. Since it was for "average" conditions that the impoundment was modeled, 179 ------- 12r Curve k,,,o, (day1) Ka(g m" day") oo o E Ol Z in x O n O (/) u) 5 iY,L.-o-v^- V X ,v \7 0 1 0.1 03 03 Dam (1970) Occoquan Dam (1973) 057 03G 057 03G • •Calculated Points Q O Observed Points 20 30 -10 50 60 70 TIME AFTER STRATIFICATION (DAYS) 00 90 -XM 100 FIGURE V-39 DISSOLVED OXYGEN DEPLETION VERSUS TIME IN THE OCCOQUAN RESERVOIR ------- it may be concluded that the model does accurately describe the behavior of the Occoquan Reservoir. 5.7.6 Toxicants It was not possible to obtain data on toxicants in Occoquan Reservoir. In order to provide a problem with some realism, published data on a priority pollutant in another reservoir were obtained. In Coralville Reservoir, Iowa, commercial fishing was banned in 1976 because of excessive accumulation of dieldrin residues in flesh of commercially important bottom feeding fish (Schnoor, 1981). The dieldrin arose from biodegraded aldrin, an insecticide in wide use along with dieldrin before cancellation of registration of both pesticides by USEPA in 1975. After 1976 there was steady diminution of dieldrin in the waters, fish, and bottom sediments of Coralville Reservoir, until the late 1970's when dieldrin levels in fish flesh declined to less than 0.3 mg/kg (Food & Drug Administration guideline). In 1979, the fishing ban was rescinded. Using the screening methods and data abstracted from Schnoor's paper, the potential dieldrin problem can be evaluated in Coralville Reservoir. Available and back-calculated data include the following values: Reservoir Dieldrin TW - 14 days = 336 hrs kow = 305000 Z = 8 feet = 2.4 m koc = 35600 C . = 0.05 yg/1 dieldrin solubility in fresh water = 200 yg/1 OC = 0.05 (estimate) So = 200 yg/1 (estimate) = 200 x 10 "6 kg/kg P = 0.9 (estimate) 181 ------- Assuming that conditions remained constant, the steady state concentration of dieldrin can be computed using the approach described in Section 5.6 as follows: C = C1n/ (1 + TW • k) where K = SED + B + k + k + kh- Evaluation of K depends on estimation of the separate rate constants. Information in Chapter 2 and in Callahan, et cfU (1977) indicate that the biodegradation rate (B) in aquatic systems is extremely small. Similarly volatilization (k ) and hydroloysis (k,) are negligible processes affecting the fate of dieldrin. Photolysis (k ) can be significant in some circumstances but the high turbidity in Coralville Reservoir indicates that minimal photolysis takes place. Consequently, K = SED. These assumptions are supported by Schnoor (1981). Calculation of the sedimentation rate constant (SED) is as follows: SED = a x D x K P K = 0.63 x kow x OC P = 0.63 x 305000 x 0.05 = 9610 D = P x 50 x i i w D = 0.9 x 200 x 10"6 x ~ = 5.36 x 336 182 ------- a =!/(!+ kpS) S = OC x 50 = .05 x 200 x 10"6 = 1 x 10"5 a = 0.912 x 5.36 x 10"5 x 9610 = 0.0047 m"1 The steady state concentration of dieldrin in Coralville Reservoir is estimated to be: C = 0.05 yg/1 (1 + (0.0047 hr'1 x 336 hr)) C = 0.019 yg/1 This value is much greater than the present fresh water quality criteria of 0.0023 dieldrin yg/1 (Federal Register: 79318-79379. Nov. 28, 1980) and would indicate a serious potential problem in the reservoir that would require significant action and study. Evaluation of bioconcentration supports this conclusion: Y = BCF x C If the default estimate is used (Section 5.6.1.6): log BCF = 0.75 log KOW - 0.23 = 3.88 BCF = 7642 Y - 7642 x 0.019 = 145 yg/kg fish flesh This value would be less than the FDA guideline. However, two published BCF values are available: 35600 from Chapter 2; 70000 from Schnoor (1981). These values produce nuch higher tissue burdens, both of which violate the FDA guideline: 183 ------- Y = 35600 x 0.019 = 676 yg/kg Y = 70000 x 0.019 = 1330 yg/kg In 1979, it is estimated that CI = 0.01 (calculated from Schnoor, 1981). Therefore, assuming other conditions are constant: C = 0.01/ (1 + (.0047 x 336)) = 0.0039 yg/1 A value about double the water quality criterion. Flesh concentration would be (using BCF = 70000): Y = 70000 x 0.0039 = 270 yg/kg This value (0.27 yg/kg) would be less than the FDA guidelines of 0.3 yg/kg and support the conclusion to lift the fishing ban. Schnoor (1981) shows the following measured data that can be compared to the screening results: 1970 1979 Water f_ish_ Hater FJ_sh Screening 0.019 1300 0.04 270 Measured 0.015 1100 0.005 250 184 ------- REFERENCES Callahan, M., M. Slimak, N. Gabel, I. May, C. Fowler, R. Freed, P. Jennings, R. Durfee, F. Whitmore, B. Maestri, W. Mabey, B. Holt, C. Gould, 1979. Water-Related Environmental Fate of 129 Priority Pollutants, Volumes I, II. USEPA Report, EPA 440/4-79-029a,b. NTIS Reports: PB80 204373, PB80 204381. b. Camp, T.R., 1968. Water and Its Impurities. Reinhold Book Corporation. New York. Chen, C.W., and G.T. Orlob, 1973. Ecologic Study of Lake Koocanusa Libby Dam. Corps of Engineers, U.S. Army, Seattle District. Chiaudani, G., and M. Vighi, 1974. "The N:P Ration and Tests with Selenastrurn to Predict Eutrophication in Lakes", Water Research, 871063^1069. Cowen, W.F. and G.F. Lee, 1976. Phosphorus Availability in Particulate Materials Transported by Urban Runoff. J. Wat. Pol. Control Fed. 48:580-591. Dean, J.D., F.J.M. Hudson, and W.B. Mills, 1979. Cheasapeake- Sandusky: Non-designated 208 Screening Methodology Demonstration. Midwest Research Institute, Kansas City, MO. USEPA Respt. for Env. Res. Lab., Athens, GA. In Press. Dillon, P., 1974. "A Manual for Calculating the Capacity of a Lake for Development", Ontario Ministry of the Environment. Dillon, P. and F. Rigler, 1975. Journal Fisheries Research Board of Canada. Vol. 32, No. 9. Dorich, R.A., D.W. Nelson and L.E. Sommers, 1980. Algal Availability of Sediment Phosphorus in Drainage Water of the Black Creek Watershed. J. Environ. Qua"). ^.-557-563. Drury, D.D., D.B. Porcella, and R.A. Gearheart, 1975. ThE effects of Artificial Destratification on the Water Quality and Microbial Populations of Hyrum Reservoir. PRJEW011-1. Utah State University, Logan, UT. Grizzard, T.J., J.P. Hartigan, C.W. Randall, J.I. Kim, A.S. Librach, and M. Derewianka, 1977. Characterizing "Runoff Pollution-Land Use". Presented at MSDGC-AMSA Workshop, Chicago. VPISU, Blacksburg, VA 24061. 66 p. Hudson, R.J.M., and D.B. Porcella, 1980. Selected Organic Consent Deere Chemicals: Addendum to Water Quality Assessment, A Screening Method For Non-designated 208 areas. USEPA Rept for Env. Res. Lab, Athens, GA, In Press. Hutchinson, G.E., 1957. A Treatise on Limnology. Vol. I. John Wiley & Sons, Inc. New York. 1015 p. 185 ------- Hydrologic Engineering Center (HEC), Corps of Engineers, 1974. Hater Quality for River-Reservoir Systems. U.S. Army Corp of Engineers. Jones, J.R. and R.W. Bachmann, 1976. Prediction of Phosphorus and Chlorophyll Levels in Lakes. JWPCF 48:2176-2182. Larsen, D.P. and H.T. Mercier, 1976. Phosphorus Retention Capacity of Lakes. J. Fish. Res. Board Can. 331731-1750.: Likens, G.E. _et _al_., 1977. Biogeochemistry of a Forested Ecosystem. Springer-Verlog, New York. 146 p. Linsley, R.K., M.A. Kohler, and J.H. Paulhus, 1958. Hydrology for Engineers. McGraw-Hill Book Company, New York. Lorenzen, M.W. et &±., 1976. "Long-Term Phosphorus Model for Lakes: Application to Lake Washington:, in Modeling Biochemical Processes in Aquatic Ecosystems. Ann Arbor Science Publishers.pp 75-91. Lorenzen, M.W., 1978. "Phosphorus Models and Eutrophication", in Press. Lorenzen, M.W., and A. Fast, 1976. A guide to Aeration/Circulation Techniques for Lake Management: For U.S. Environmental Protection Agency, Corvallis, Oregon. Lund, J., 1971. Water Treatment and Examinatjon, Vol. 19. pp 332-358. Marsh, P.S., 1975. Siltation Rates and Life Expectancies of Small Headwater Reservoirs in Montana. Report No. 65, Montana University Joint Water Resources Research Center. Rast, W. and G.F. Lee., 1978. Summary Analysis of the North American (US Portion) OECD Eutrophication Project. EPA-600/3-78-008. USEPA, Corvallis, Oregon 93770. 454 p. Sakamoto, M., 1966. Archives of Hydrobiology, Vol. 62. pp 1-28. Schnoor, J.L., 1981. Fate and Transport of Dieldrin in Coralville Reservoir: Residues in Fish and Water Following a Pesticide Ban. Science. 211:804-842. Stumm, W., and J.J. Morgan, 1970. Aquatic Chemistry. Wiley-Interscience, New York. Vollenweider, R.A., 1976. Advances in defining critical loading levels for Phpsphorus in Lake Eutrophication. Mem. 1st. Ital. Idrobiol. 33: 53-83. U.S. Department of Commerce, 1974. Climatic Atlas of the United States, U.S. Department of Commerce, Environmental Sciences Services Administration Environmental Data Service, Washington, D.C. U.S. Environmental Protection Agency, 1975. National Water Quality Inventory. Report to Congress, EPA-440/9-75-014. Zison, S.W., W.B. Mills, D. Deimer, C.W. Chen, 1978. Rates, Constants, and Kinetics Formulations in Surface Water Quality Modeling. EPA-600/3-78-105. USEPA, Athens, GA 30605. 316 p. 186 ------- GLOSSARY OF TERMS Significant variables are shown with typical units. Units must be compatible or use conversion factors (Chapter 1). Note that some symbols are used for more than one term. A Lake surface area, m2 - sediment area, m2 a Fraction of pollutant in solution = 1/(1+(K x S)), unitless -1 P B Biodegradation rate, hr B(T) Biodegradation rate, corrected for temperature T, hr~ BCF Bioconcentration factor, unitless Bo Initial microbial biodegradation rate, uncorrected for temperature or nutrient concentration, hr~ C Reservoir concentration at time, t, mg] C Initial concentration, mgl~ -1 C Concentration of phosphorus, ygPl P _3 C Total exchangeable phosphorus concentration in the sediments, g m -1 C Toxicant concentration sorbed on sediment, mg 1 -1 C. Concentration of BOD at time t, mg 1 -1 C Concentration in water phase, mg 1 w -1-3 C Steady-state water column phosphorus concentration, mg 1 , g m W C- Steady state influent concentration, mg/1 in o C Steady-state water column BOD, g m C t Weight concentration C -j Volumetric concentration D Depth, m D Discharge channel depth, ft D Sedimentation rate constant = P x S x Q/V, mg 1" day" D Dilution rate, day" D1 Flowing layer depth, ft D" Inflow channel depth, ft D Mean depth, m D Depth to thermocline, m D, Mean hypolimnion depth, m Di Depth at the ith cross-section, m Do Diffusivity of oxygen in water (2.1x10 m2 sec , 20°C) 187 ------- D Weight density of a particle, Ib ft 33 Dw Weight density of water, Ib ft , g cm 2-1 DW Pollutant diffusivity in water, m sec d Number of days per time period, days d Particle diameter, cm f 1 + (T x K), unitless -2 g Acceleration due to gravity, 32.2 ft sec ISD Intensity of light at Secchi depth, relative units I Initial intensity of light at surface, relative units K Pollutant removal rate, = SED + B + k + k + k, , hr"1 -1 v P n K Net rate of phosphorus removal, hr K, Specific rate of phosphorus transfer to the sediments, m yr~ l<2 Specific rate of phosphorus transfer from the sediments, m yr K., Fraction of total phosphorus input to sediment that is available for the exchange process, unitless K Reaeration rate, hr a -1 Ka. Reaeration coefficient, m hr K Distribution coefficient between organic sediment and water, unitless K.. First order decay rate for water column BOD at 20°C, day" K. Benthic BOD decay rate at 20°C, day"1 4 -3 -1 K Mean rate of BOD loading from all sources, g m day -3 -1 K (algae) Algal contribution to BOD loading rate, g m~ day cl K (trib) Tributary or point source contribution to BOD loading rate, a -3 -1 g m day x Kb - -«s -KJ -(1/TW), day'1 k Extinction coefficient, m e -1 k. Hydrolysis rate, hr -1 k Photolysis rate, hr k Photolysis rate constant uncorrected for depth and turbidity of the lake, rf kr Mean rate of BOD settling out onto the impoundment bottom, -1 day"1 k Volatilization rate, hr v 188 ------- koc Organic carbon based partition coefficient, unitless kow Octanol-water coefficient, unitless _? L Areal BOD load, gm -2 -1 L Phosphorus loading, g m yr P -2 L Steady-state benthic BOD load, g m ss _j M Total annual phosphorus loading, g yr M Proportion of algal biomass expressed as an oxygen demand (unitless) MW Molecular weight, g mole" OC Sediment organic carbon fraction, unitless AO Dissolved oxygen decrease due to hypo!imnion BOD, mg I"1 AO. Dissolved oxygen decrease due to benthic demand, mg 1 L _i 0 Dissolved oxygen at time t = 0, mg 1 o i Ot Dissolved oxygen at time t, mg 1 p Sediment trapping efficiency, unitless 1 >_ P ;> 0 -2 -1 P Primary productivity rate, g Carbon m day P Total phosphorus in the water column, mg m~3 PI Influent phosphorus, mg I"1 QI Mean annual inflow, m3 yr Q Mean Annual outflow, m3 yr~* q Hydraulic loading (Z/T J.myr'1 s w R Reynolds number, unitless r Radius, ft S Stoichiometric conversion from algal biomass as carbon to BOD, 2.67, unitless S Input suspended organic sediment = OC x So, mg 1"^ S- Mass of sediment in inflow per unit time, mg 1~^ S Input of suspended sediment, mg 1 S. Sediment trapped, metric tons yr SD Secchi depth, m SDR Sediment delivery ratio, unitless SED Sorption and sedimentation rate (toxicant at equi1ibriurn with sediments), hr~* T Temperature, degrees centigrade 189 ------- V Lake or impoundment volume, m3 V,. Hypolimnion volume, 1 H V Sediment volume, m3 V Terminal velocity of a spherical particle, ft sec" max W Wind speed, m sec" Y Tissue concentration of pollutant, ug kg" fish flesh y number of years Z depth, m Z mean depth, m ~2 u Absolute viscosity of water, Ib sec ft , g sec cm ' p Mass density of a particle, slugs ft P 0 p Mass density of water, slugs ft W T Mean hydraulic residence time (V/Q),days 190 ------- Chapter 6 ESTUARIES 6.1 INTRODUCTION 6.1.1 General Estuaries are of primary social, economic, and ecologic importance to America. Forty-three of 110 of the Department of Commerce's Standard Metropolitan Statistical Areas are on estuaries (DeFalco, 1967). Estuaries are the terminal or transfer point for essentially all waterborne national and international commerce in this country, and biologically are more productive on a mass per unit area basis than any other type of water body. Essentially all conservative wastes and much of the nonconservative wastes discharged into any inland stream in America eventually pass into an estuary. Yet these coastal formations on which there is such a demand for services are less stable geologically than any other formation found on the continent (Schubel, 1971). Sedimentation processes, for example, are filling, destroying, or at least altering all estuaries. While this process is always rapid in a geological sense, the actual length of time required for complete estuarine sedimentation is a function primarily of the stability of the sea level, the rate of sediment influx, and the intra-estuarine circulation pattern (Schubel, 1971). The instability, variation, and complexity of estuaries make water quality assessment and prediction especially difficult, yet the demands placed on estuaries require a most active water quality management program. This chapter will describe a systematic approach which may be used to provide estuarine water quality assessment and prediction. Its purpose is two-fold. First, the planner will be provided the capability of making elementary assessments of current estuarine water quality. Second, methodologies are presented by which the planner can evaluate changes in water quality which might result from future changes in waste loading. 191 ------- Chapter 3 provided methodologies for assessing the waste load directly entering an estuary. Chapter 4 provided methodologies which can be used to assess the water quality of a river or stream as it enters an estuary. The output of these chapters will provide information about present and projected estuarine water quality which can be used to identify regions having greatest water quality problems, water quality parameters of special concern, and areas for which subsequent computer study is necessary. Methods presented below comprise a screening tool which may be used by the planner to focus attention on critical spatial regions and water quality parameters. These can then be fully assessed using computer models or other techniques, as desired. 6.1.2 Estuarine Definition It is difficult to provide a concise, comprehensive definition of an estuary. The basic elements included in most current definitions are that an estuary is: a. a semi-enclosed coastal body of water, b. freely connected to the open sea, c. influenced by tidal action, and d. a water body in which sea water is measurably diluted with fresh water derived from land drainage (Pritchard, 1967; Pritchard and Schubel, 1971). The seaward end of an estuary is established by the requirement that an estuary be semi-enclosed. Because this boundary is normally defined by physical land features, it can be specifically identified. The landward boundary is not as easily defined, however. Generally tidal influence in a river system extends further inland than does salt intrusion. Thus the estuary is limited by the requirement that both salt and fresh water be measurably present. Accordingly, the landward boundary may be defined as the furthest measurable inland penetration of sea salts. The location of 192 ------- this inland boundary will vary substantially from season to season as a function of stream flows and stream velocities and may be many miles upstream from the estuarine mouth (e.g. approximately 40 miles upstream on the Potomac River, 27 miles on the James River, and approximately 16 miles upstream for the small Alsea Estuary in Oregon) (Pritchard, 1971). This definition also separates estuaries from coastal bays (embayments) by the requirement for a fresh water inflow and measurable sea water dilution. 6.1.3 Types of Estuaries While the above definition provides adequate criteria for segregating estuaries from other major types of water bodies, it does not provide a means to separate the various types of estuaries from one another. The variations in estuarine circulation patterns and resulting variations in pollutant dispersion from estuary to estuary make classification a necessary part of any water quality assessment. Two basic estuarine classification systems have been used in recent years to accomplish estuarine subclass separation: a topographical system and a physical processes system (Dyer, 1973, Chapter 2 or Ippen, 1966, Chapter 10). 6.1.3.1 Topographical Classification Under a topographical system, estuaries are divided into four subclasses. These are briefly described below. a. Drowned River Valley (Coastal Plain Estuary). These estuaries are the result of a recent (within the last 10,000 years) sea level rise which has kept ahead of sedimentation processes at a river's mouth. Such estuaries are, quite literally, rivers whose lower basins have been drowned by the rising oceans. Coastal plain estuaries are characteristically broad, relatively shallow estuaries (rarely over 30 m deep) with extensive layers of recent sediment. 193 ------- b. Fjord-like Estuaries. These estuaries are usually glacially formed and are extremely deep (up to 800 m) with shallow sills at the estuarine mouth. Fjord-like estuaries are restricted to high latitude mountainous regions and are not found in the United States outside of Alaska and Puget Sound in the state of Washington. c. Bar-built Estuaries. When offshore barrier sand islands build above sea level and form a chain between headlands broken by one or more inlets, a bar-built estuary is formed. These estuaries are characteristically very shallow, elongated, parallel to the coast, and frequently are fed by more than one river system. As a result bar-built estuaries are usually very complex hydrodynamically. A number of examples of bar-built estuaries can be found along the southeast coast of the United States. d. Tectonic Process Estuaries. Tectonic estuaries exist as the result of major tectonic events (movement of tectonic plates with associated faulting or subsidence and coastal volcanic activity). San Francisco Bay is a good example of an American estuary of this type. Based on this topographic classification system, the vast majority of American estuaries fall into the drowned river class. As a result, this system is not functional for categorization of American estuaries. The classification system described below is based on physical processes and is more useful. Further, the parameters used in physical classification are directly applicable to estuarine pollution analysis. Consequently, a physical parameter classification system will be used for the water quality assessment approach to be presented. 194 ------- 6.1.3.2 Physical Process Classification Physical process classification systems are generally based on the velocity and salinity patterns in an estuary. Using these two parameters, estuaries can be divided into three classes, each of which is of potential importance to planners concerned with American coastal plain estuaries. The classes are: stratified, partially mixed, and well mixed. The general behavior of salinity and velocity regimes in the three types of estuaries has been described by a number of researchers (Glenne, 1967, Duxbury, 1970, Pritchard, 1960, and Dyer, 1973, among others) and is summarized below. a. Stratified (Salt Wedge) Estuary. In this type of estuary, large fresh water inflows ride over a salt water layer which intrudes landward along the estuary bottom. Generally there is a continuous inland flow in the salt water layer as some of this salt water is entrained into the upper seaward-moving fresh water flow. Tidal action is not sufficient to mix the separate layers. Salinity (S) and Velocity (U) profiles and a longitudinal schematic of this flow pattern are shown in Figure VI-1. The Mississippi River Estuary is usually a salt wedge estuary. Well Mixed. In a well mixed estuary, the tidal flow (or the tidal prism*) is much greater than the river outflow. Tidal mixing forces create a vertically well mixed water column with flow reversing from ebb to flood at all depths. Typical salinity and velocity profiles and a longitudinal flow schematic for a well mixed estuary are shown in Figure VI-2. As examples, the Delaware and Raritan River estuaries are both normally well mixed. *The tidal prism is that volume of water which enters an estuary during an incoming (flood) tide and equals high tide estuarine volume minus low tide volume. 195 ------- SALINITY *l.etters cnrrcspond to cross sections FIGURE VI-1 TYPICAL MAIN CHANNEL SALINITY AND VELOCITY FOR STRATIFIED ESTUARIES 196 ------- SURFACE BOTTOM SURFACE BOTTOM c o a> o O VELOCITY C,D- •jr >• O i- ll ------- c. Partially Mixed. Partially mixed estuaries lie between stratified and well mixed in terms of flow and stratification characteristics. Tide-related flows in such estuaries are substantially greater than river flows. Significant salinity gradients exist as in fully stratified estuaries, but are much less steep. While velocity at all depths normally reverses with ebb and flood tide stages, it is possible for net inland flow to be maintained in the lowest layers. Typical salinity and velocity profiles and a longitudinal schematic flow diagram are shown in Figure VI-3. There are many partially mixed coastal plain estuaries in the United States; the lower James River Estuary is typical. Classification primarily depends on the river discharge at the time of classification. Large river flows result in more stratified estuaries while low flow conditions in the same estuaries can lead to full mixing. Thus the classification of any single estuary is likely to vary from season to season as river flows vary. As examples, many west coast estuaries are partially mixed in winter when river flows are high and are well mixed in summer when river flows are very low. 6.1.4 Po11u t ant F1ow in an Est uary The importance of understanding the basic types of estuarine systems may be appreciated by briefly reviewing the general advective movements of a pollutant released into each of the three types of estuaries (summarized from Pritchard, 1960). The associated spatial and temporal variability of pollutant levels have water system management as well as water quality implications. If a pollutant flow of density greater than the receiving water column is introduced into a salt wedge type estuary, the pollutant tends to sink into the bottom salt water layer and a portion can be advectively carried inland toward the head of the estuary. Frictionally induced vertical entrainment of the pollutant into the surface water flow is slow, residence time of the pollutant is high, and the time required to flush the pollutant 198 ------- SURFACE BOTTOM SURFACE BOTTOM I o O VELOCITY 0 a> u> I U) SALINITY *Letters denote channel cross-sections FIGURE VI-3 TYPICAL MAIN CHANNEL SALINITY AND VELOCITY PROFILES FOR PARTIALLY MIXED ESTUARIES 199 ------- from the estuary is also high. Some pollutants which are sufficiently dense and stable remain in or settle to the bottom layer of water, and are not transported out of a salt wedge estuary. Such constituents build up in the estuarine sediment layer. Conversely, if a pollutant of lower density than the receiving water column is introduced into a salt wedge estuary, it remains in the surface layer and is readily flushed from the system. This is the case because seaward flows strongly predominate in this layer. At the opposite end of the estuary classification scale, a pollutant introduced into a well mixed estuary is advectively transported in a manner independent of the pollutant's density. Tidal forces cause turbulent vertical and lateral mixing. The pollutant is carried back and forth with the oscillatory motion of the tides and is slowly carried seaward with the net flow. Pollutants introduced into partially mixed estuaries are dispersed in a manner intermediate between the transport patterns exhibited in well mixed and stratified estuaries. Pollutant transport is density dependent but nevertheless involves considerable vertical mixing. Eventual flushing of the pollutant from an estuary in this case depends on the relative magnitudes of the net river outflow and the tidal seawater inflow. 6,1.5 Estuarine Complexity and Major Forces Before outlining the complexities of estuarine systems, a brief review of the nomenclature used in this chapter will be helpful. This information is shown in Figure VI-4. This figure shows top, side, and cross sectional views of an estuary and indicates the basic estuarine dimensions. Additionally, the relationship between tidal elevation (or tidal stage) and surface water velocity is shown in the upper right quadrant of Figure VI-4. The complexities of estuarine hydrodynamics are evident from even the brief qualitative descriptions presented above. Many variations in flow pattern and many of the forces acting on an estuarine water column have been ?GO ------- IOZ Mouth CO d |_H Z m j—i m co o m Tl o Head O m < rn a) a> Q Q I! TIDAL VELOCITY ^-Ebb TIDAL ELEVATION ------- omitted in order to permit a verbal description of the normally predominant. phenomena, and it should be understood that the descriptions do not fully account for the complexities of estuarine motion. Estuarine circulation may be conceived as a three-dimensional flow field with variations possible in salinity and velocity along the longitudinal, the vertical, and the lateral axes. As a result of this complexity, and because an estuary is a transitional zone between fresh water and marine systems, great variations in a number of major water quality and physical parameters are possible. For example: a. pH. Typical ocean pH is 7.8 to 8.4. Typically, rivers are slightly acidic (pH<7). Thus the pH can change from slightly acidic to basic across an estuary with resulting major changes in chemical characteristics of dissolved and suspended constituents. pH variations from 6.8 to 9.25 across an estuary have been recorded (Perkins, 1974, p. 29). b. Salinity. Over the length of an estuary, salinity varies from fresh water levels (typically less than 1 ppt) to oceanic salinity levels (usually 32 ppt to 34 ppt)*. Moreover salinity at any given location in an estuary may vary substantially over one tidal cycle and over the depth of the water column at any single point in time. Salinity variations are especially significant in estuarine calculations for a variety of reasons. First, salinity distribution can be used to predict the distribution of pollutants; second, salinity is a prime determinant of water density; and third, variations in salinity affect other major water quality parameters. For example, the saturated dissolved oxygen concentration normally diminishes by 2 mg/1 as salinity increases from 0 to 35 ppt. c. River Flow. River flow is a major determinant of estuarine circulation and flushing characteristics. Instantaneous flow rates for some western rivers vary by orders of magnitude from *opt represents parts per thousand by mass. Sometimes the symbol °/oo is used. 202 ------- winter high flow to summer low flow periods (Goodwin, e_t a_l_., 1970). These differences in river flow result in major variations in estuarine water quality characteristics. d. Time. Estuarine water quality parameters vary over several separate time scales. First, variations occur with each tidal cycle over a period of hours. Second, tidal cycles vary in mean amplitude from spring (maximum amplitude) to neap tides (minimum amplitude) every two weeks. This affects water quality since flushing characteristics are in part dependent on the tidal prism which is, in turn, dependent on tide stage. Third, there are seasonal variations in river flow, temperature and waste loadings. The four factors just listed affecting the range and rate of variation of estuarine parameters pose part of the difficulty in analyzing estuarine water quality. In order to avoid large errors, both small time increments and small spatial increments must be used. This, in turn, necessitates a large number of individual calculations to fully analyze the variation of even a single parameter over the estuary and sometimes requires the use of a computer model. Further complicating the analytical process is the large number of independent forces acting on the estuarine water column which should be considered. This group includes (from Harleman and Lee, 1969): a. Ocean tides b. Local wind stresses c. Bottom roughness and bottom sediment types d. Channel geometry e. Coriolis forces'* f. Nearby coastal features and coastal processes *Coriolis forces reflect the effect of a rotating reference plane (the earth) on particle motion. The net effect is to cause a water flow to drift to one side as it propogates down a channel. The same effect tends to laterally segregate fresh water flows (moving from head to mouth) and salt water inflows (moving from mouth to head) in an estuary and in the northern hemisphere to create a counterclock-wise flow pattern with fresh water to the right (looking from the head of the estuary toward the mouth) flowing toward the sea and salt water on the left flowing toward the head of the estuary. ------- 6.1.6 Methodology Summary A variety of techniques are presented in this chapter to assess water quality in estuaries. Table VI-1 summarizes the techniques and indicates if they are applicable to one-dimensional (well-mixed) or two-dimensional (vertically stratified) estuaries. Many of the techniques can be applied to conventional or toxic pollutants. If decay rates for toxic pollutants are needed, Chapter 2 can be used. It is redundant to describe in detail each method at this point in the chapter, because, the procedures are presented later. As a general statement, however, most of the methods for prediction of water quality apply to continuous, steady-state discharges of pollutants. The discharges can be located anywhere within the estuary, from head to mouth. Multiple sources of pollutants can be analyzed by applying the method of superposition, which is illustrated subsequently. Although no single sequence of calculations must be followed to use the methodology, Figure VI-5 shows a suggested procedure. It is often useful to begin by classifying the estuary by season to find out when it is well mixed and when it is stratified. If the estuary is never well mixed, then the tools listed in Table VI-1 pertaining to one-dimensional estuaries should not be used. Users are cautioned that the methods in this chapter are of a simplified nature, and consequently there are errors inherent in the calculations. Additionally, inappropriate data can produce further systematic errors. Data used should be appropriate for the period being studied. For example, when salinity profiles are needed, they should correspond to steady flow periods close to the critical period being analyzed. Even though the methods presented in the chapter are amenable to hand calculations, some methods are more difficult to apply than others. The fraction of freshwater and modified tidal prism methods are relatively easy to apply, while the advective-dispersion equations offer greater computational challenge. Since the advective-dispersion equations require numerous calculations, the user might find it advantageous to program the methods on a hand calculator (e.g. TI-59 or HP-41C). 204 ------- TABLE VI-1 SUMMARY OF METHODOLOGY FOR ESTUARINE WATER QUALITY ASSESSMENT Calculations Methods Type of Estuary Applicable* Estuarine Classification Flushing Time Pollutant Distribution Thermal Pollution Turbidity Sedimentation • Hansen and Rattray • Flow ratio Fraction of freshwater Modified tidal prism Fraction of freshwater (conservative pollutants)1" Modified tidal prism (conservative or first-order decay pollutants)'" Dispersion-advection equations (conservative,first-order decay pollutants, and dissolved oxygen) Pritchard's Box Model (conservative pollutants)" Initial dilution Pollutant concentration at completion of initial dilution (conservative pollutants, PH, dissolved oxygen) Farfield distribution (conservative and first-order pollutants, and dissolved oxygen) AT of water passing through condenser Maximum discharge temperature Thermal block criterion Surface area criterion Surface temperature criterion Turbidity at completion of initial dilution Suspended solids at the completion of initial dilution Light attenuation and turbidity relationship Secchi disk and turbidity relationship Description of sediment movement Settling velocity determination Null zone calculations one- or two-dimensional one- or two-dimensional one-dimensional one-dimensional one-dimensional one-dimensional one-dimensional two-dimensional one- or two-dimensional one- or two-dimensional two-dimensional not applicable not applicable one- or two-dimensional one- or two-dimensional one- or two-dimensional one- or two-dimensional one- or two-dimensional one- or two-dimensional one- or two-dimensional one- or two-dimensional one- or two-dimensional two-dimensional *0ne dimensional means a vertically well mixed system. A two dimensional estuary is vertically stratified. These methods apply to either conventional or toxic pollutants. 205 ------- CLASSIFY ESTUARY < tSTUAHY VERTICALLY > ^\ "iXED s' T YES CALCULATE FLUSHING TIMES V PREDICT POLLUTANT DISTRIBUTIONS USING ONE OR MORE OF THE FOLLOWING METHODS, _ _ (CONSERVATIVE POLLUTANTS) MODIFIED TIDAL PRISM METHOD (CONSERVATIVE AND TOXIC POLLUTANTS) ADVECTlQN-DlSPERSlON LOCATIONS (CONSERVATIVE AND ! TOXIC POLLUTANTS AND j DISSOLVED QXYG6N) 1 No ./'is rue POLLUTANT ^\^^ * *X^^ Ul SLMAWGtL) 'HKOlKjH S* ^^^ AN OUTFALL .s [YES V _._ COMPUTE CRITICAL INITIAL DILUTIOMS ^f FOLLOWING INITIAL DILUTION, CONCENTRATIONS, rt', DISSOLVED OXYGEN, ETC. SOLIDS AHD Toulon-* foLLOvti«r, INITIAL DILUTIOM T PREDICT FARFIELD POLLUTANT AND D!SSOv,VED OXYGEH CONCENTRATIONS m tSTUARY IS \ I STRATIFIED J CALCULATE CONSERVATIVE POLLUTANT DISTRIBUTION USING PRITCHARD'S Box MODEL 1 f No s<^ Is SOURCE ^x^^ V PREDICT TEMPERATURF DISTRIBUTION fel w^ PREDICT TURBIDITY IMPACTS V PREDICT SEDIMENTATION ^ f END OF St-RFENING \ I CALCULAT IONS J ^j SELECT MARIIINAL AND CRITICAL AREAS FOR ^ FURTHER STUDY PERFORM I DETAILED l- ANALYSIS j FIGURE VI-5 SUGGESTED PROCEDURE TO PREDICT ESTUARINE WATER QUALITY 206 ------- 6.1.7 Present Water-Quality Assessment The first step in the estuarine water quality assessment should be the evaluation of existing water quality. Before an analysis of the impact of future waste load changes is made, the planner should know whether or not current estuarine water quality is acceptable, marginal, or substandard. By far the best way to assess existing water quality is to measure it. The planner should attempt to locate other agencies which might have already collected acceptable samples and/or data. Candidate organizations include the United States Geologic Survey, the U.S. Army Corps of Engineers, state water quality control and monitoring agencies, and engineering and oceanographic departments of local colleges and universities. If such data cannot be located, a data collection program could be undertaken. If at all possible, high tide, and especially low tide in-situ measurements and samples should be collected along the full length of the estuary's main channel and in all significant side embayments. Analyses should then be made in an appropriate laboratory facility. If funds for such data collection efforts are not available, the use of a mathematical estimation of existing water quality is an alternative. The methods presented in subsequent sections and applied to the existing discharges can be used. However, it should be remembered that actual data are preferable to a mathematical estimate of existing water quality. 6.2 ESTUARINE CLASSIFICATION 6.2.1 General Section 6.1.7 discussed making a first estimate of current estuarine water quality. This section begins a calculation methodology designed to look at the effect of future changes in waste loading patterns. The goal of the classification process presented below is to predict the applicability of the hand calculations to be presented. The classification process is normally the first step to be taken in the 207 ------- calculation procedure since it reveals which techniques can be applied. 6.2.2 C1 a^ssification Methodo 1ogy The classification system recommended for purposes of hand calculations is based on salinity and velocity profiles within the estuary. As both of these parameters vary seasonally and spatially for each estuary, their use will result in a range of values rather than in one single classification number. The following section will describe in detail the procedure for use of this system, and show examples of the procedure. 6.2.3 C a 1 c u_1 a t i on P r o c e d u re Hansen and Rattray (1966) developed an estuarine classification system using both salinity stratification and water circulation patterns (based on water column velocities). This procedure involves the calculation of values for two parameters at various points along the main estuarine channel and the plotting of these intersections on the graph shown in Figure VI-6. Figure VI-7 shows plots made by Hansen and Rattray for various estuaries at a single point in time. It should be noted that each estuary is not represented by a point but by a line connecting the points calculated for the mouth and head areas. The area designations (e.g. la, Ib, 2b) on Figure VI-6 were related by Hansen and Rattray to previously used classification titles (e.g. stratified, well mixed). In general, area la corresponds to well mixed estuaries. Area Ib has the water circulation pattern of a well mixed estuary yet shows increased stratification. Areas 2 and 3 correspond to the "partially mixed" class of estuaries with area 3 showing more significant lateral circulation within the estuary. Designations 2a/b and 3a/b, as was true of la and Ib, indicate increasing degrees of vertical stratification. Type 3b includes fjord-type estuaries. Area 4 represents highly stratified, salt wedge estuaries. 208 ------- Increasing longitudinal circulation AS „:! t FIGURE VI-6 ESTUARINE CIRCULATION-STRATIFICATION DIAGRAM 10 O 10 io'2h 115 (Station code: M, Mississippi River mouth; C, Columbia River estuary; J, James River estuary; NM, Narrows of the Mersey estuary, JF, Strait of Juan .de Fuca; S, Silver Bay. Subscripts h and 1 refer to high and low river discharge; numbers indicate distance (in miles) from mouth of the James River estuary. t FIGURE VI~7 EXAMPLES OF ESTUARINE CLASSIFICATION PLOTS (FROM HANSEN AND RATTRAY, 1966) 209 ------- 6.2.4 Stratification-Circulation Diagram Interpretation The closer an estuary falls to the lower left hand corner of a stratification-circulation diagram the more vertically and laterally homogeneous it is. On the stratification-circulation diagram (Figure VI-6), two types of zonal demarcation can be seen. First are the diagonally striped divisions between adjacent estuarine classifications used by Hansen and Rattray to indicate a transitional zone between separate classifications. The second is a wide solid band arching around the lower left corner of the diagram. Estuaries falling primarily inside of this band (to the lower left of the band) are those for which the one dimensional calculation methods may be applied to obtain reasonably accurate results. If an estuary falls outside of this band, the planner should use only the methods presented which pertain to stratified estuaries, or use computer analyses. Within the band is a borderline or marginal zone. Calculations for one-dimensional estuaries can be used for estuaries falling principally within this zone, however the accuracy of the calculations will be uncertain. The two parameters used with the stratification-circulation diagram are described below: a. Stratification Parameter: The stratification parameter is defined as: AS Stratification Parameter = =— (VI-1) *o where AS = time averaged difference in salinity between surface and bottom water (S. . . - S £ \ v bottom surface), ppt and, SQ = cross-section mean salinity, ppt 210 ------- The diagramatic relationship of these values is shown in Figure VI-8. b. Circulation Parameter: The circulation parameter is defined as: U Circulation parameter = rr- (VI-2) Uf where U = net non-tidal sectional surface velocity (surface velocity through the section averaged over a tidal cycle) measured in ft/sec. See Figure VI-8 for a diagramatic representation of Us- and, U- = mean fresh water velocity through the section, ft/sec. In equation form, Uf=-f (VI-3) where R = fresh water (river) inflow rate, ft3/sec, and A = cross-sectional area of the estuary through the point being used to calculate the circulation pattern and stratification parameters based on a mean tide surface elevation, ft2. If good cross-sectional area data are not available, cross-sectional profiles can be approximated from the U.S.Geological Survey (USGS) coastal series topographical maps, or, more recently, from NOAA National Ocean Survey charts. 211 ------- CIRCULATION PARAMETER Velocity * STRATIFICATION PARAMETER Salinity * i/ AS u - Uf" A * Both velocity and salinity values for these profiles are averaged over a tidal cycle (net velocity and salinity) rather than being instantaneous values. Of the two the stratification parameter is much less sensitive to variations over a tidal cycle and can be approximated by mean tide values for salinity. Surface velocity (U } must be average over a tidal cycle. FIGURE VI-8 CIRCULATION AND STRATIFICATION PARAMETER DIAGRAM 212 ------- The circulation and stratification parameters should be plotted for high and low river flow periods and for stations near the mouth and head of the estuary. The area enclosed by these four points should then include the full range of possible instantaneous estuary hydrodynamic characteristics. In interpreting the significance of this plotted area, by far the greater weight should be given to the low river flow periods as these periods are associated with the poorest pollutant flushing characteristics and the lowest estuarine water quality. The interpretation of the circulation-stratification diagrams will be explained more fully after an example of parameter computation. EXAMPLE VI-1 Calculation of Stratification and Circulation Parameters The estuary for this example is the Stuart Estuary which is shown in Figure VI-9. The estuary is 64,000 feet long, is located on the U.S. west coast, and is fed by the Scott River. Two stations were selected for parameter calculation (A and B) with station A located on the southern edge of the main channel 6,500 feet from the estuary's mouth and station B in center channel 47,500 feet from the mouth (16,500 feet from the head of the estuary). Necessary salinity data were obtained from the coastal engineering department of a nearby university. USGS gage data were available for river flow, and, as a result of its own dredging program, the local district office of the U.S. Corps of Engineers could provide cross-sectional profiles in the approximate areas of both stations. The cross-sections are labeled (1) and (2) on Figure VI-9. The mean low tide depth reading on NOAA Coastal charts was used to verify Corps data. Current meters were tied to buoy channel markers at A and B to provide velocity data. The information obtained from these various sources is shown in graphical form in Figure VI-10. 213 ------- OCEAN FIGURE VI-9 THE STUART ESTUARY 214 ------- S(%o) AT MEAN TIDE Surface Bottom B c Flood (FT/SEC) 10 15 \B 35 2000 1700 -2 Years Ago -Last Year -Average J F M A M J Id lA MONTHS * Monthly Average Discharge Rates 0 N D WINTER _ SUMMER CROSS SECTION OF A N CROSS SECTION OF s N FIGURE VI-10 STUART ESTUARY DATA FOR CLASSIFICATION CALCULATIONS 215 ------- The calculations proceed as follows: a. Stratifiction Parameter: STATION Jbp_ttpm __ surface -—s -- 33 - 30 . gc 11 R 31.5-24.2 ,, 27.8 " ---- 14.5 - 10.5 „ " 1 7 £.' " •3t 4 - 2'1 - 58 3.25 " — ci r-if-trD 1 1 1 MTTD b. Circulation Parameter 1. Calculate A^'s using cross sectional information on Figure VI-10 Aa = (630 ft) (20 ft) (%) + (630 ft) (20 ft) + (1590 ft) (20 ft) (Jg) = 34,800 ft2 Ab = (2580 ft) (16 ft) (h) + (1720 ft) (16) (h) = 34,400 ft2 For most cross-sections it is advisable to use more finely divided segments than in the simple example above in order to reduce the error associated with this approximation. The method for this calculation, however, is identical regardless of the number of regular segments used. 2. Calculate U^'s (with R and A^ values obtained from Figure VI-10) STAT.OH 550 ft3/sec „ . rBj.]0-2,,,,e.. 3.48xl------- 3. Calculate Si Jf Us values are read from Figure VI-10. The precise value for Us is the integral of the velocity curve (area under "ebb" velocity curve minus the area under the "flood" velocity curve) divided by the elapsed time period (length of one tidal cycle). If the elapsed time for flood flow at a station is only slightly below the elapsed time for ebb flow Us may be approximated as (uebb(max) - uflood(max) STATION . 0.15 ft/sec . , 5 1.58xJO"2ft/sec iii 0.2 ft/see . 3 , 5.17xlO~Zft/sec ~ 0.3 ft/sec ._ 1.60x)0"'ft/$ec 0.* ft/iec . , 5. Z3xlO ft/see SUtVKR The circulation-stratification plots for the Stuart Estuary are shown in Figure VI-11 with points As (station A, summer value), Aw (station A, winter Value), Bs (station B, summer value), and BW (station B, winter value). As indicated, this estuary shows a significant amount of vertical stratification (especially at station A) but little evidence of major lateral non-homogeneity. END OF EXAMPLE VI-1 217 ------- AS Uf FIGURE VI-11 ESTUARINE CIRCULATION-STRATIFICATION DIAGRAM 218 ------- Turning to Figure VI-11, the Stratification-Circulation diagram for the Stuart Estuary, it is apparent that this estuary lies principally within the marginal area. Moreover, the low flow classification (line A -B ) also lies o j primarily within the marginal area. Thus, the planner for the Stuart Estuary should calculate an additional criterion (see below) to help determine the suitability of using the calculation procedures for well mixed estuaries. If the Stuart Estuary plotted more predominately below the marginal zone, the planner could proceed with flushing time calculations since the estuary would then meet the well mixed classification criteria. It should be noted that the data for the Stuart Estuary produced a fairly tight cluster of data points. As can be seen in Figure VI-12, the salinity profiles for one west coast estuary (the Alsea River and Estuary along the central Oregon coast) vary considerably more from season to season than those of the Stuart Estuary. This increased variation would produce a far greater spread in the summer and winter AS/S0 parameter values. 6.2.5 Flow Ratio Calculation If application of the above classification procedure results in an ambiguous outcome regarding estuary classification, another criterion should be applied. This is the flow ratio calculation. Schultz and Simmons (1957) first observed the correlation between the flow ratio and estuary type. They defined the flow ratio for an estuary as: R F =- (VI-4) where F = the flow ratio, R = the river flow measured over one tidal cycle (measured in m3 or ft3 ) and 219 ------- I-' U- Q. Ld Q 25 15 0 10 20 ' ALSEA RIVER S(%o) AT HIGH TIDE 0 WINTER-Feb. 9,1968 20 33 30 2511510 5 SPRING-May 9,1968 33 30 25 20 15 10 5 0 SUMMER-Aug. 9,1968 0 I 2 3 4 5 6 7 8 9 10 II 12 13 14 MILES UPSTREAM FIGURE VI-12 ALSEA ESTUARY SEASONAL SALINITY VARIATIONS (FROM GIGER, 1972) 220 ------- P = the estuary tidal prism (in m3 or ft3) Thus the flow ratio compares the tidally induced flow in an estuary with the river induced flow. Schultz and Simmons observed that when this ratio was on the order of 1.0 or greater, the associated estuary was normally highly stratified. Conversely, ratios of about 0.1 or less were usually associated with very well-mixed estuaries and ratios in the range of 0.25 were associated with partially mixed estuaries. A flow ratio of 0.2 or less warrants inclusion of the estuary in the hand calculation process for one dimensional estuaries. Flow ratios in the range 0.2 to 0.3 should be considered marginal. Estuaries with flow ratios greater than 0.3 should not be included in the one-dimensional category. EXAMPLE VI-2 Calculation of the Flow Ratio for an Estuary The following data apply to the Patuxent Estuary, Maryland: R, total river discharge over one tidal cycle = 1.42 x 105m3 (low flow) and 3.58 x 106m3 (high flow) P, estuary tidal prism volume = 3.51 x 107m3 The flow ratios for the Patuxent Estuary at low and high river flows are thus: 5 3 1.42xl05 m 3.51x10' F - - a o 10 high flow 3.51xl07 m3 221 ------- Values of F<0.1 are usually associated with well mixed estuaries. The F values calculated above indicate a well mixed estuary. However, historical data indicate the Patuxent River Estuary is partially stratified at moderate and high river flows. END OF EXAMPLE VI-2 When tidal data are not available, NOAA coastal charts may be used to estimate the difference between mean high tide and mean low tide estuary surface areas. As can be seen in the cross-section diagram in Figure VI-13 the estuarine tidal prism can be approximated by averaging the MLT and MHT surface areas and multiplying this averaged area by the local tidal height. Mean tidal heights (approximately 1 week before or after spring tides) should be used for this calculation. As indicated in Figure VI-13, the estuary can be conveniently subdivided into longitudinal sections for this averaging process, to reduce the resulting error. Table VI-2 lists tidal prisms estimated for many U.S. estuaries. These values may be used as an alternate to tidal prism calculations. 6.3 FLUSHING TIME CALCULATIONS 6.3.1 General Flushing time is a measure of the time required to transport a conservative pollutant from some specified location within the estuary (usually, but not always, the head) to the mouth of the estuary. Processes such as pollutant decay or sedimentation which can alter the pollutant's distribution within the estuary are not considered in the concept of flushing time. 222 ------- Mean Tide- MHT Surface' /-MLT Surface* X TIDAL HEIGHT** .,,,... P. (section i) = section Length x tidal height x I /MHT width + MLT width \ P estuary for all sections * Widths obtained from NOAA tide table for the area **Avai Table from local Coast Guard Stations FIGURE VI-13 ESTUARY CROSS-SECTION FOR TIDAL PRISM CALCULATIONS 223 ------- TABLE VI-2 TIDAL PRISMS FOR SOME U.S. ESTUARIES (FROM O'BRIEN, 1969 AND JOHNSON, 1973) Estuary Plum Island Sound, Mass. Fire Island Inlet, N.Y. Jones Inlet, N.Y. Beach Haven Inlet (Little Egg Bay), N.J. Little Egg Inlet (Great Bay), N.J. Brigantine Inlet, N.J. Absecon Inlet (before jetties), N.J. Great Egg Harbor Entr, N.J. Townsend Inlet, N.J. Hereford Inlet, N.J. Chincoteague Inlet, Va. Oregon Inlet, N.C. Ocracoke Inlet, N.C. Drum Inlet, N.C. Beaufort Inlet, N.C. Carolina Beach Inlet, N.C. Stono Inlet, S.C. North Edisto River, S.C. St. Helena Sound, S.C. Port Royal Sound, S.C. Calibogue Sound, S.C. Wassaw Sound, Ga. Ossabaw Sound, Ga. Sapelo Sound, Ga. St. Catherines Sound, Ga. Coast Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Tidal Prism (ft3) 1.32 x 109 2.18 x 109 1.50 x 109 1.51 x 109 1.72 x 109 5.23 x 108 1.65 x 109 2.00 x 109 5.56 x 108 1.19 x 109 1.56 x 109 3.98 x 109 5.22 x 109 5.82 x 108 5.0 x 109 5.25 x 108 2.86 x 109 4.58 x 109 1.53 x 1010 1.46 x 1010 3.61 x 109 8.2 x 109 6.81 x 109 7.36 x 109 6.94 x 109 224 ------- TABLE VI-2 (Cont.) Estuary Doboy Sound, Ga. Altamaha Sound, Ga. Hampton River, Ga. St. Simon Sound, Ga . St. Andrew Sound, Ga. Ft. George Inlet, Fla. Old St. Augustine Inlet, Fla. Ponce de Leon, Fla. (before jetties) Delaware Bay Entrance Fire Island Inlet, N.Y. East Rockaway Inlet, N.Y. Rockaway Inlet, N.Y. Masonboro Inlet, M.C. St. Lucie Inlet, Fla. Nantucket Inlet, Mass. Shinnecock Inlet, N.Y. Moriches Inlet, N.Y. Shark River Inlet, N.J. Manasguan Inlet, N.J. Barnegat Inlet, N.J. Absecon Inlet, N.J. Cold Springs Harbor (Cape May), N.J. Indian River Inlet, Del. Winyah Bay, S.C. Charleston, S.C. Savannah River (Tybee Roads) , Ga. Coast Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Tidal Prism (ft3) 4.04 x 109 2.91 x 109 1.01 x 109 6.54 x 109 9.86 x 109 3.11 x 108 1.31 x 109 5.74 x 108 1.25 x 1011 1.86 x 109 7.6 x 108 3.7 x 109 8.55 x 108 5.94 x 108 4.32 x 108 2.19 x 108 1.57 x 109 8.46 x 10 1 .48 x 108 1.75 x 108 6.25 x 108 1.48 x 109 6.50 x 108 5.25 x 108 3.02 x 109 5.75 x 109 3.1 x 109 225 ------- TABLE VI-2 (Cont.) Estuary St. Marys (Fernandina Harbor), Fla. St. Johns River, Fla. Fort Pierce Inlet, Fla. Lake Worth Inlet, Fla. Port Everglades, Fla. Bakers Haulover, Fla. Captiva Pass, Fla. Boca Grande Pass, Fla. Gasparilla Pass, Fla. Stump Pass, Fla. Midnight Pass, Fla. Big Sarasota Pass, Fla. New Pass, Fla. Longboat Pass, Fla. Sarasota Pass, Fla. Pass-a-Grille Johns Pass, Fla. Little (Clearwater) Pass, Fla. Big (Dunedin) Pass, Fla. East (Destin) Pass, Fla. Pensacola Bay Entr. , Fla. Perdido Pass, Ala. Mobile Bay Entr., Ala. Barataria Pass, La. Caminada Pass, La. Calcasieu Pass, La. San Luis Pass, Tex. Coast Atlantic Atlantic Atlantic Atlantic Atlantic Atlantic Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Gulf of Mexico Tidal Prism (ft3) 4.77 x TO9 1.73 x 109 5.81 x 108 9.0 x 108 3.0 x 108 3.6 x 108 1.90 x 109 1.26 x 1010 4.7 x 108 3.61 x 108 2.61 x 108 7.6 x 108 4.00 x 108 4.90 x 108 8.10 x 108 1.42 x 109 5.03 x 108 6.8 x 108 3.76 x 108 1.62 x 109 9.45 x 109 5.84 x 108 2.0 x 1010 2.55 x TO9 6.34 x 108 2.97 x TO9 5.84 x 108 226 ------- TABLE VI-2 (Cont.) Estuary Venice Inlet, Fla. Galveston Entr., Tex. Aransas Pass, Tex. Grays Harbor, Wash. Willapa, Wash. Columbia River, Wash. -Ore. Necanicum River, Ore. Nehalem Bay, Ore. Tillamook Bay, Ore. Netarts Bay, Ore. Sand Lake, Ore. Nestucca River, Ore. Salmon River, Ore. Devils Lake, Ore. Siletz Bay, Ore. Yaquina Bay, Ore. Alsea Estuary, Ore. Siuslaw River, Ore. Umpqua, Ore. Coos Bay, Ore. Caquille River, Ore. Floras Lake, Ore . Rogue River, Ore. Chetco River, Ore. Smith River, Ca. Lake Earl, Ca. Freshwater Lagoon, Ca. Stove Lagoon, Ca. Big Lagoon, Ca . Coast Gulf of Mexico Gulf of Mexico Gulf of Mexico Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Paci fie Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Tidal Prism (ft ) 8.5 x 107 1.59 x 1010 1.76 x 109 1.3 xlO10 1.3 x 1010 2.9 x 1010 4.4 x 107 4.3 x 108 2.5 x 109 5.4 x TO8 1.1 x TO8 2.6 x 108 4.3 x 107 1.1 x 108 3.5 x 108 8.4 x 108 5.1 x 108 2.8 x 108 1.2 x 109 1.9 x 109 1.3 x 108 6.8 x 107 1.2 x 108 2.9 x 107 9.5 x 107 5.1 x 108 4.7 x 107 1.2 x 108 3.1 x 108 227 ------- TABLE VI-2 (Cont.) Estuary Mad River, Calif. Humbolt Bay, Calif. Eel River, Calif. Russian River, Calif. Bodega Bay, Calif. Tomales Bay, Calif. Abbotts Lagoon, Calif. Drakes Bay, Calif. Bolinas Lagoon, Cal if. San Francisco Bay, Calif. Santa Cruz Harbor, Calif. Moss Landing, Calif. Morro Bay, Calif. Marina Del Rey, Calif. Alamitos Bay, Calif. Newport Bay, Calif. Camp Pendleton, Calif. Aqua Hedionda, Calif. Mission Bay, Calif. San Diego Bay, Calif. Coast Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Pacific Tidal Prism (ft3) 2.4 x 107 2.4 x 109 3.1 x 108 6.3 x 107 1.0 x 108 1.0 x 109 3.5 x 107 2.7 x 108 1.0 x 108 5.2 x 1010 4.3 x 106 9.4 x 107 8.7 x 107 6.9 x 107 6.9 x 107 Q 2.1 x 10tt 1.1 x 107 4.9 x 107 3.3 x 108 1.8 x 109 228 ------- It was mentioned earlier in this chapter that the net non-tidal flow in an estuary is usually seaward* and is dependent on the river discharge. The non tidal flow is one of the driving forces behind estuarine flushing. In the absence of this advective displacement, tidal oscillation and wind stresses still operate to disperse and flush pollutants. However, the advective component of flushing can be extremely important. Consider Tomales Bay, California as an example. This small, elongated bay has essentially no fresh water inflow. As a result there is no advective seaward motion and pollutant removal is dependent upon dispersion and diffusion processes. The flushing time for the bay is approximately 140 days (Johnson, e_t &]_., 1961). This can be compared with the Alsea Estuary in Oregon having a flushing time of approximately 8 days, with the much larger St. Croix Estuary in Nova Scotia having a flushing time of approximately 8 days (Ketchum and Keen, 1951), or with the very large Hudson River Estuary with a short flow flushing time of approximately 10.5 days (Ketchum, 1950). 6.3.2 Procedure Flushing times for a given estuary vary over the course of a year as river discharge varies. The critical time is the low river flow period since this period corresponds with the minimum flushing rates. The planner might also want to calculate the best flushing characteristics (high river flow) for an estuary. In addition to providing a more complete picture of the estuarine system, knowledge of the full range of annual flushing variations can be useful in evaluating the impact of seasonal discharges (e.g. fall and winter cannery operation in an estuary with a characteristic summer fresh water low flow). Further, storm sewer runoff normally coincides with these best flushing conditions (high flow) and not with the low flow, or poorest flushing conditions. Thus analysis of storm runoff is often better suited for high flow flushing conditions. However, the low flow calculation should be considered for use in primary planning purposes. *While net flow is always seaward for the estuaries being considered here, it is possible to have a net upstream flow in individual embayments of an estuary. While this occurrence is rare in the United States, an example of such a situation is the South Bay of San Francisco Bay where freshwater inflows are so small that surface evaporation exceeds freshwater inflow. Thus, net flow is upstream during most of the year. 229 ------- There are several ways of calculating flushing time. Two methods are presented here: the fraction of freshwater method and the modified tidal prism method. 6.3.3 Fraction of Fresh Hater Method The flushing time of a pollutant, as determined by the fraction of freshwater method is Vf f R where Vf = volume of freshwater in the estuary T^ = flushing time of a pollutant which enters the head of the estuary with the river flow Equation VI-5 is equivalent to the following concept of flushing time which is more intuitively meaningful: M Tf = 7 (VI-6) T M where M = total mass of conservative pollutant contained in the estuary M = rate of pollutant entry into the head of the estuary with the river water Since the volume of freshwater in the estuary is the product of the fraction of freshwater (f) and the total volume of water (V), Equation VI-5 becomes: 230 ------- T =- 'f R (VI-7) If the estuary is divided into segments the flushing time becomes: fiVi Tf"r "V (VI'8: Equation VI-8 is more general and accurate than the three previous expressions because both f^ (the fraction of freshwater in the ith segment) and R- (the freshwater discharge through the itli segment) can vary over distance within the estuary. Note that the flushing time of a pollutant discharged from some location other than the head of the estuary can be computed by summing contributions over the segments seaward of the discharge. A limitation of the fraction of freshwater method is that it assumes uniform salinity throughout each segment. A second limitation is that it assumes during each tidal cycle a volume of water equal to the river discharge moves into a given estuarine segment from the adjacent upstream segment, and that an equal volume of the water originally in the segment moves on to the adjacent one downstream. Once this exchange has taken place, the water within each segment is assumed to be instantaneously and completely mixed and to again become a homogeneous water mass. Proper selection of estuarine segments can reduce these errors. 6.3.4 Calculation of Flushing Time by Fraction of Freshwater Method This is a six step procedure: 1. Graph the estuarine salinity profiles. 2. Divide the estuary into segments. There is no minimum or maximum number of segments required, nor must all segments be of the same length. The divisions should be selected so that mean segment salinity is relatively constant over the full 231 ------- length of the segment. Thus, stretches of steep salinity gradient will have short segments and stretches where salinity remains constant may have very long segments. Example VI-3 provides an illustration. 3. Calculate each segment's fraction of fresh water by: f _ Ss - S1 Ss (VI-9) where f-j = fraction of fresh water for segment "i" Ss = salinity of local sea water*, °/oo and S.j = mean salinity for segment "i", °/oo 4. Calculate the quantity of fresh water in each segment by: W. = f. x V. (VI-1Q) i i i where Wi = quantity of fresh water in segment "i" and V.j = total volume of segment11!" at MIL *Sea surface salinity along U.S. shores vary spatially. Neuman and Pierson (1966) mapped Pacific mean coastal surface salinities as varying from 32.4 o/oo at Puget Sound to 33.9 o/0o at the U.S.-Mexico border; Atlantic mean coastal surface salinities as varying from 32.5 °/oo in Maine to 36.2 °/oo at the southern extreme of Florida; and Gulf coast salinities as varying between 36.2 o/0o and 36.4 °/oo. Surface coastal salinities in Long Island Sound (Hardy, 1972) and off Long Island south coast (Hydroscience, 1974) vary between 26.5 and 28.5 °/oo. 232 ------- 5. Calculate the exchange time (flushing time) for each segment by: (VI-11) where T. = segment flushing time, in tidal cycles and R = river discharge over one tidal cycle 6. Calculate the entire estuary flusing time by summing the exchange times for the individual segments: n where Tf = estuary flushing time, in tidal cycles n = number of segments. Table VI-3 shows a suggested method for calculating flushing time by the fraction of freshwater method. 233 ------- TABLE VI-3 SAMPLE CALCULATION TABLE FOR CALCULATION OF FLUSHING TIME BY SEGMENTED FRACTION OF FRESHWATER METHOD Segment Number Mean Segment Salinity S.(ppt) Mean Segment Length (m) Mean Segment Cross-sectional Area (m2) Segment Mean Tide Volume V,- (m3) Fraction of River Water f _ Ss-Si fi Ss River Water Volume W.= fixVi (m3) n EV 1=1 Segment Flushing Time T. = WI./R (tidal cycles) ro oo I/I LU Q. ZD I ------- EXAMPLE VI-3 Mashing Time Calculation by Fraction of Fresh__Wa_ter_Me^th_od_ This example pertains to the Patuxent Estuary. This estuary has no major side embayments, and the Patuxent River is by far its largest source of fresh water. This estuary therefore lends itself well to analysis by the segmented fraction of fresh water method. Salinity profiles for July 19, 1978 are used to find segment salinity values. Chesapeake Bay water at the mouth of the Patuxent Estuary had a salinity of 10.7 ppt (S.). The Patuxent River discharge over the duration of one tidal cycle is R = (12 m3/sec)(12.4 hr/tidal cycle)(3600 sec/hr) = 5.36 x 105 mVtidal cycle A segmentation scheme based on the principles laid out above is used to divide the estuary into eight segments; their measured characteristics are shown Table VI-4. The segmentation is shown graphicaly on the estuary salinity profile (Figure VI-14). The next step is to find the fraction of fresh water for each segment. For segment 1, V S' f l = -— where j = fraction of fresh water, segment 1 S = salinity of local seawater 235 ------- TABLE VI-4 PATUXENT ESTUARY SEGMENT CHARACTERISTICS FOR FLUSHING TIME CALCULATIONS no GO Mean Segment Salinity Segment Number S., ppt 8 10.3 7 9.5 6 8.7 5 7.6 4 5.8 3 3.3 2 1.8 1 0.8 Segment Length meters 10,400 10,400 6,100 6,100 5,800 5,000 4,650 4,650 Mean Segment Cross-Sectional Area meter2 16,000 12,500 11,400 7,500 4,300 3,100 2,200 1,700 Mean Tide Seqment Volume Vl 3 meters " 16.6xl07 13-OxlO7 6.95xl07 4.58xl07 2.49xl07 1.55xl07 1.02xl07 0.79xl07 ------- GO —I 10 8 SALINITY (PPD 4 2 10 20 30 DISTANCE FROM HEAD OF ESTUARY (Km) 40 50 CHESAPEAKE BAY FIGURE VI-14 PATUXENT ESTUARY SALINITY PROFILE AND SEGMENTATION SCHEME USED IN FLUSHING TIME CALCULATIONS, ------- Sa = measured mean salinity for segment 1 = 10.7 ppt-0.8 ppt = Q g3 i 10.7 ppt The calculation is reported in Table VI-4 for segments 2 through 8. The volume of fresh water (river water) in each segment is next found using the formula W. . f. x V, For segment 1, Wt = fi x Vi = 0.93 (0.79 x 107m3) = 7.35 x 106m3 The flushing time for each segment is next calculated by For segment 1, = 7.35 x 106m3/(5.36 x 105m3/tidal cycle) = 13.7 tidal cycles Fraction of freshwater, river water volume and flushing time values for the eight segments are compiled in Table VI-5. The final step is to determine the flushing time for the estuary. In this case, 8 Tf = Z T. = T 1 = 1 1 11.4 + 27.2 + 24.6 +24.8 + 21.5 + 20.0 + 15.8 + 13.7 = 159 tidal cycles, or 2.74 months 238 ------- Co TABLE VI-5 FLUSHING TIME FOR PATUXENT ESTUARY Segment Number 8 7 6 5 4 3 2 1* Mean Segment Salinity Si, PPt 10.3 9.5 8.7 7.6 5.8 3.3 1.8 0.8 Segment Length meters 10,400 10,400 6,100 6,100 5,800 5,000 4,650 4,650 Mean Segment Cross-Sectional Area meter2 16,000 12,500 11,400 7,500 4,300 3,100 2,200 1,700 Segment Mean Tide Volume Vi meter3 16.6x10' 13.0x10' 6.95x10' 4.58x10' 2.49x10' 1.55x10' 1.02x10' 0.79x10' Fraction of River Water (Ss =\0.7) 0.037 0.112 0.19 0.29 0.46 0.69 0.83 0.93 River Water Volume Wi = fi x Vi (meters3) 6.14xl06 14.6xl06 13.2xl06 13.3xl06 11.5xl06 10.7xl06 8.47xl06 7.35xl06 Segment Flush Time Ti = wi/R tidal cycles 11.4 27.2 24.6 24.8 21.5 20.0 15.8 13.7 Sum = 159 tidal cycles or 2.74 months *In this numbering scheme segment 1 is the most upstream segment. ------- END OF EXAMPLE VI-3 6.3.5 Branched Estuaries and the Fraction of Freshwater Method Branched estuaries, where more than one source of freshwater contributes to the salinity distribution pattern, are common. The fraction of freshwater method can be directly applied to estuaries of this description. Consider the estuary shown in Figure VI-15, having two major sources of freshwater (River 1, Rl; and River 2, R2). The flushing time for pollutants entering the estuary with river flow R2 is: Tf (R2) = T! + T2 + T3 + T4 + T5 + T6 = fjVi f2V2 f3V3 f4V, f5V5 f6V6 For the pollutants entering with RJ5 the flushing time is: T ,„ . Va Vb Vc fsVs T f ( R i) - __ + —- + — + f Ri Ri Ri Ri+R2 Ri+R2 The flushing time computations are similar in concept for the case of a single freshwater source, modified to account for a flow rate of Rj + R2 in segments 5 and 6. 6.3.6 Modified Tidal Prism Method This method divides an estuary into segments whose lengths are defined by the maximum excursion path of a water particle during a tidal cycle. Within each segment the tidal prism is compared to the total segment volume as a measure of the flushing potential of that segment per tidal cycle (Dyer, 1973). The method assumes complete mixing of the incoming tidal prism waters with the low tide volumes within each segment. Best results have been obtained in estuaries when the number of segments is large (i.e. 240 ------- ro FIGURE VI-15 HYPOTHETICAL TWO-BRANCHED ESTUARY ------- when river flow is very low) and when estuarine cross-sectional area increases fairly quickly downstream (Dyer, 1973). The modified tidal prism method does not require knowledge of the salinity distribution. It provides some concept of mean segment velocities since each segment length is tied to particle excursion length over one tidal cycle. A disadvantage of the method is that in order to predict the flushing time of a pollutant discharged midway down the estuary, the method still has to be applied to the entire estuary. The modified tidal prism method is a four-step methodology. The steps are: 1. Segment the estuary. For this method an estuary must be segmented so that each segment length reflects the excursion distance a particle can travel during one tidal cycle. The innermost section must then have a tidal prism volume completely supplied by river flow. Thus, where PO = tidal prism (intertidal volume) of segment "0" and R = river discharge over one tidal cycle. The low tide volume in this section (V0) is that water volume occupying the space under the intertidal volume P0 (which has just been defined as being equal to R). The seaward limit of the next seaward segment is placed such that its low tide volume (Vj) is defined by: V = P + V (VI-13) i o o 242 ------- P! is then that intertidal volume which, at high tide, resides above Vi. Successive segments are defined in an identical manner to this segment so that: Vi ' PM + Vl (vi-14) I Thus each segment contains, at high tide, the volume of water contained in the next seaward section at low tide. 2. Calculate the exchange ratio (r) by: r. = —— (VI-15) 1 Pi+Vi Thus the exchange ratio for a segment is a measure of a portion of water associated with that segment which is exchanged with adjacent segments during each tidal cycle. 3. Calculate segment flushing time by: T_J_ (VI-16) where T.J = flushing time for segment "i", measured in tidal cycles. 4. Calculate total estuarine flushing time by summing the individual segment flushing times: n Tf = L Ti 243 ------- where L. = total estuary flushing time and n = number of segments. Table VI-6 shows a suggested method for calculating flushing time by the modified tidal prism method. EXAMPLE VI-4 Estuary Flushing Time Calculation by the Modified Tidal Prism Method The Fox Mill Run Estuary, Virginia, was selected for this example. During low flow conditions, the discharge of Fox Mill Run has been measured at 0.031 m3/sec. R = river discharge over one tidal cycle = 0.031 m3/sec x 12.4 hrs/tidal cycle x 3600 sec/hr = 1384 mVtidal cycle. The estuary flushing time is found in four steps: 1. Segmentation From bathymetric maps and tide gage data, cumulative upstream volume was plotted for several positions along the estuary (See Figure VI-16). 244 ------- TABLE VI-6 SAMPLE CALCULATION TABLE FOR ESTUARINE FLUSHING TIME BY THE MODIFIED TIDAL PRISM METHOD Segment Number Segment Dimensions Starting Distance Above Mouth (m) Ending Distance Above Mouth (m) Distance of Center Above Mouth (m) Segment Length (m) Subtidal Water Volume, Vi (m3) Intertidal Water Volume (m3) Segment Exchange Ratio ri n £ T< = Segment Flushing Time, Ti (Tidal Cycles) ro rs t/i UJ ------- 1000-, 500- intertidal volume co OT Q) ------- Since P~ = R P0 = 1384 m3. Reading across the graph from "a" to the intertidal volume curve, then down the subtidal volume curve and across to "b", VQ = 490 m3. The known cumulative upstream water volume also establishes the downstream segment boundary. Reading downward from the subtidal volume curve to "c", a VQ of 490 m3 corresponds to an upstream distance of 2,700 meters for the segment 0 lower boundary. The low tide water volume for the next segment can be found by the equation: V = P + V Vl P0 V0 or V, = 1384 + 490 = 1874 m3 Since the graphs of Figure VI-16 are cumulative curves, it is necessary, when entering a V- value in order to determine a P. value, to sum the upstream V. 's. For Vj the cumulative upstream low-tide volume is: VQ + V = 490 + 1874 r 2364 m3 Entering the graph where the subtidal volume is equal to 2,364 m3 (across from "d"), we can move upward to read the corresponding cumulative intertidal volume "e" on the vertical scale, and downward to read the downstream boundary of segment 1 at "f" on the horizontal scale. The cumulative upstream intertidal volume is 5900 m3. Since 5900 m3 = PQ + Pj 247 ------- P, = 5900-1384 = 4516 m3 For segment 2, Vz = PJ + Y! = 1874 + 4516 = 6390 m3 To find P2, it is necessary to enter the graph at a cumulative subtidal volume of V0 + Vl + V2 = 49° + 1874 + 639° = 8759 m3(across from "9") This yields a cumulative intertidal volume of 14,000 m3 (across from "h") and a downstream segment boundary of 1,650 m3 "i". The tidal prism of Segment 2 is found by: 14000 = PQ + Pj + P2 or P0 + 14000 - 1384 - 4516 + 8100 m3 The procedure is identical for Segment 3. For this final segment, ''3 and P3 = 36,000 m3 V3 = 14,490 m3 Dimensions and volumes of the four segments established by this procedure are compiled in Table VI-7. 2. The exchange ratio for segment 0 is found by PO 1384 m3 0 PQ+VO 1384 m3+490 m3 248 ------- TABLE VI-7 DATA AND FLUSHING TIME CALCULATIONS FOR FOX MILL RUN ESTUARY Segment Number 0 1 2 3 Segment Dimensions Starts at this Distance Above Mouth meters 3,200 2,700 2,240 1,650 Stops at this Distance Above Mouth meters 2,700 2,240 1,650 180 Center Point Distance Above Mouth meters 2,950 2,470 1,945 915 Segment Length meters 500 460 590 1,470 Water Volume at Low Tide Vi meters3 490 1,874 6,390 14,490 Intertidal Vol ume Pi , meters3 1,384 4,516 8,100 36,000 Exchange Ratio For Segment i ri 0.74 0.71 0.56 0.71 Flushing Time for Segment i Ti 1.35 1.41 1.79 1.41 ro £T. = 5.96 tidal cycles ------- Exchange ratios are calculated similarly for the other three segments . 3. Flushing time for each segment "i" is qiven by so T - _L - _I_ = i 35 To " r0 0.74 i>JD Exchange ratios and flushing times for the four segments are shown in Table VI-7. 4. Flushing time for the whole estuary is found by 3 Tf * * Ti or T i=0 T = 1.35+1.41+1.79+1.41 = 5.96 tidal cycles = 73.9 hours = 3.1 days END OF EXAMPLE VI-4 250 ------- 6.4 FAR FIELD APPROACH TO POLLUTANT DISTRIBUTION IN ESTUARIES 6.4.1 Introduction Analysis of pollutant distribution in estuaries can be accomplished in a number of ways. In particular, two approaches, called the far field and near field approaches, are presented here (Sections 6.4 and 6.5, respectively). As operationally defined in this document, the far field approach ignores buoyancy and momentum effects of the wastewater as it is discharged into the estuary. The pollutant is assumed to be instantaneously distributed over the entire cross-section of the estuary (in the case of a well-mixed estuary) or to be distributed over a lesser portion of the estuary in the case of a two-dimensional analysis. Whether or not these assumptions are realistic depends on a variety of factors, including the rapidity of mixing compared to the kinetics of the process being analyzed (e.g. compared to dissolved oxygen depletion rates). It should be noted that far field analysis (either one- or two- dimensional) can be used even if actual mixing is less than assumed by the method. However, the predicted pollutant concentrations will be lower than the actual concentrations. Near field analysis considers the buoyancy and momentum of the wastewater as it is discharged into the receiving water. Pollutant distribution can be calculated on a smaller spatial scale, and assumptions such as "complete mixing" or "partial mixing" do not have to be made. The actual amount of mixing which occurs is predicted as an integral part of the method itself. This is a great advantage in analyzing compliance with water quality standards which are frequently specified in terms of a maximum allowable pollutant concentration in the receiving water at the completion of initial dilution. (Initial dilution will be defined later in Section 6.5.2) The following far field approaches for predicting pollutant distribution are presented in this chapter: • fraction of freshwater method, t modified tidal prism method, • dispersion-advection equations, and 251 ------- • Pritchard's Box Model. The near field analysis uses tabulated results from an initial dilution model called MERGE. At the completion of initial dilution predictions can be made for the following: • pollutant concentrations • pH levels, and • dissolved oxygen concentrations. The near field pollutant distribution results are then used as input to an analytical technique for predicting pollutant decay or dissolved oxygen levels subsequent to initial dilution. The remainder of Section 6.4 will discuss those methods applicable to the far field approach. 6.4.2 Continuous Flow of Conservative Pollutants The concentration of a conservative pollutant entering an estuary in a continuous flow varies as a function of the entry point location. It is convenient to separate pollutants entering an estuary at the head of the estuary (with the river discharge) from those entering along the estuary's sides. The two impacts will then be addressed separately. 6.4.2.1 River Discharges of Pollutants The length of time required to flush a pollutant from an estuary after it is introduced with the river discharge has already been calculated, and is the estuarine flushing time. Now consider a conservative pollutant continuously discharged into a river upstream of the estuary. As pollutant flows into the estuary, it begins to disperse and move toward the mouth of the estuary with the net flow. If, for example, the estuary flushing time is 10 tidal cycles, 10 tidal cylces following its initial flow into the estuary, some of the pollutant is flushed out to the ocean. Eventually, a steady-state condition is reached in which a certain amount of pollutant enters the estuary, and the same amount is flushed out of the estuary during 252 ------- each tidal cycle. The amount of this pollutant which resides in the estuary at steady-state is a function of the flushing time. From the definition of flushing time, the amount of fresh water (river water) in the estuary may be calculated by: = Tf R where W = quantity of freshwater in the estuary T = estuary flushing time and R = river discharge over one tidal cycle. Using the same approach, the quantity of freshwater in any segment of the estuary is given by: W. = T. R (VI-19) where Wi = quantity of freshwater in the ith segment of the estuary and T. = flushing time for the ith segment calculated by the fraction of freshwater method. 253 ------- If a conservative pollutant enters an estuary with the river flow, it can be assumed that its steady-state distribution will be identical to that of the river water itself. Thus, M. = W. C = T. R C i i r i r and where M- = quantity of pollutant in estuary segment "i" C = concentration of pollutant in the river inflow C,- = concentration of pollutant in estuary segment "i" assuming all of pollutant "i" enters the estuary with the river discharge. Thus direct discharges into the estuary are excluded and V- - water volume segment "i". The same values for C^ and M^ may also be obtained by using the fraction of freshwater, fj , for each segment by: . = f. Cr (VI-22) 254 ------- and M. = C. V. (VI-23) Thus both the quantity of a pollutant in each segment and its concentration within each segment are readily obtainable by either of the above methods. The use of one of these methods will be demonstrated in Example VI-5 below for calculation of both C- and M-. EXAMPLE VI-5 Calculation of Concentration of Conservative River Borne Pollutant in an Estuary The Patuxent Estuary is the subject of this example. The problem is to predict the incremental concentration increase of total nitrogen (excluding N2 gas) in the estuary, given that the concentration in river water at the estuary head is 1.88 mgN/1. Assume that total nitrogen is conservative and that the nitrogen concentration in local seawater is negligible. The segmentation scheme used in Example VI-2 (fraction of freshwater calculation) will be retained here. For each segment, the total nitrogen concentration is directly proportional to the fraction of freshwater in the segment: C1 = fi Cr The total nitrogen concentration for the uppermost segment is therefore given by: Ci = 0.93 (1.88 mgN/1) =1.75 mgN/1 255 ------- For the next segment it is: C2 = 0.83 (1.88 mgN/1) = 1.56 mgN/1, and so on. Nitrogen concentrations for all the segments are compiled in Table VI-8. Note that these are not necessarily total concentrations, but only nitrogen inputs from the Patuxent River. The incremental mass of nitrogen in each segment is found by: M. = W. C i i r The W. values for the eight segments were determined in Example VI-2. For segment 1, the incremental nitrogen is given by: = (7.35xl06m3)(1.88 mgN/1)(103l/m3) = 1.38xl010 mg or 13,800 kg Increased total nitrogen (in kilograms) for the entire estuary is shown in Table VI-9. END OF EXAMPLE VI-5 In this example, low tide volumes were used to calculate M- since low tide volumes had been used to calculate f^'s. The approach assumes that C.j 's are constant over the tidal cycle and that M.J 's are constant over the tidal cycle. This leads to the assumption that calculation of a low tide C-j and M.J will fully characterize a pollutant in an estuary. This, however, is not strictly true. Figure VI-17 depicts one tidal cycle in an estuary and 256 ------- TABLE VI-8 POLLUTANT DISTRIBUTION IN THE PATUXENT RIVER Segment Number* Fraction in 8 7 6 5 4 3 2 1 River * From Example VI-2 ** These are the increment of Freshwater* Segment fn- 0.037 0.112 0.19 0.29 0.46 0.69 0.83 0.93 1.00 concentrations Resultant Pollutants** Concentration = f; x 1.88 mgN/1 0.07 0.21 0.36 0.55 0.86 1.30 1.56 1.88 1.88 of total nitrogen in the estuary due to the river-borne input. 257 ------- TABLE VI-9 INCREMENTAL TOTAL NITROGEN IN PATUXENT RIVER, EXPRESSED AS KILOGRAMS (See Problem VI-5) Segment Number River Water Volume W-=f.xV meters3 Incremental Total N M,= W^l.88) Kilograms 8 7 6 5 6.14xl06 14.6xl06 13.2xl06 13.3xl06 11,500 27,40 24,800 25,000 ll.SxlO6 21,600 10.7xl06 20,100 8.47xl06 15,900 7.35xl06 13,800 258 ------- Period for tidal flushing of "pollutant from estuary \ TIDAL ELEVATION W,, Nominal "Mean" Period of river dis- charge into estuary FIGURE VI-17 RIVER BORNE POLLUTANT CONCENTRATION FOR ONE TIDAL CYCLE 259 ------- shows the periods of the cycle during which a pollutant is flushed out of the estuary and during which river discharge brings pollutants into the estuary. During periods of high tide, rising tidal elevation blocks river discharge and backs up river flow in the lower stretches of the river. Figure VI-17 also shows the resulting quantity of a pollutant in residence in the estuary (W ) over the tidal cycle. This variation over the tidal cycle as a percentage of NL is dependent on the flushing time but is usually small. The change in the total volume of water in an estuary over a tidal cycle is equal to the tidal prism which is often of the same magnitude as the low tide volume. As an example, the Alsea Estuary in Oregon has Pt = 5.1 x 108 ft3 while Vt = 2.1 x 108 (Goodwin, Emmet, and Glenne, 1970). Thus the variation in estuarine volume is 2.5 times the low tide volume. As a result, estuarine volume variations over a tidal cycle have a much greater impact on variations in pollutant concentrations in the estuary than do changes in the quantity of pollutant present in the estuary over a tidal cycle. It is important to note, however, that low tidal volume and low MF nearly coincide, so that variations in mean pollutant concentrations are less severe than are estuarine water mass changes. This qualitative description of pollutant flow into and out of an estuary is somewhat simplistic since it assumes that high tide and low tide at the mouth of an estuary coincide with those at the head of the estuary. This is usually not the case. There is normally a lag time between tidal events at an estuarine mouth and those at its head. Thus river discharge into the estuary which depends on tidal conditions at the head, and tidal discharge which depends on tidal conditions at the mouth, are not as directly tied to each other as indicated in Figure VI-17. While WF does not vary substantially over a tidal cycle under steady-state conditions, the mean concentration of a pollutant in an estuary (CF) does. Alsea Estuary data can be used to show this CE variation over a tidal cycle. Using data for the estuary as a whole (mean concentration), the equations for this comparison are: W£ = Wp Tf (VI-24) 260 ------- and CE = ME/(Vt Pt), (VI-25) with Wr = (566.4 Mg/ft3) (4.64xl06 ft3/tidal cycle), or W = 2.628xl09 yg/tidal cycle. Then, Mr = (2.628xl09 yg/tidal cycle)(20.8 tidal cycle), ME = 5.466xl010ug, and C . = 5.466xl010 yq/2.1x!08 ft3, E(low) or Cp,-, x= 260.31 yg/ft3, or 46 percent of river concentration. However, CE(hi h) = 5.466xl010yg/(2.1xl08 ft3+5.1x!08 ft3), C,-,, . , N = 75.92 yq/ft3, or 13 percent of river concentration. E(rngn) In an actual estuary, the concentration of a pollutant is not a stepwise function as indicated by segment C. values, but is more realistically a continuous spectrum of values. By assigning the longitudinal midpoint of each segment a concentration value equal to that 261 ------- segment's C-, a resulting continuous curve can be constructed as shown in Figure VI-18. This type of plot is useful in estimating pollutant concentrations within the estuary. It can also be used, however, to estimate maximum allowable Cr to maintain a given level of water quality at any point within the estuary. This latter use of Figure VI-18 is based on determining the desired concentration level (Cv) and then using the ratio of A C to C to calculate an allowable C . x r r 6.4.2.2 Other Continuous Conservative Pollutant Inflows In the previous section, an analysis was made of the steady-state distribution of a continuous flow pollutant entering at the head of an estuary. The result was a graph of the longitudinal pollutant concentration within the estuary (Figure VI-18). This section addresses a continuous, conservative pollutant flow entering along the side of an estuary. Such a pollutant flow (e.g. the conservative elements of a municipal sewer discharge, industrial discharge, or minor tributary) is carried both upstream and downstream by tidal mixing, with the highest concentration occurring in the vicinity of the outfall. Once a steady state has been achieved, the distribution of this pollutant is directly related to the distribution of fresh river water (Dyer, 1973). The average cross-sectional concentration at the outfall under steady-state conditions is: c ~ P f (VI-26) o R o where C = mean cross-sectional concentration of a pollutant at the point of discharge, mass/volume 262 ------- DISTANCE (x) FROM HEAD OF ESTUARY (in 1000FT) (M9/D FIGURE VI-18 ALSEA ESTUARY RIVERBORNE CONSERVATIVE POLLUTANT CONCENTRATION 263 ------- Q = discharge rate of pollutant, mass/tidal cycle fQ = segment fraction of freshwater R = river discharge rate, volume/tidal cycle. Downstream of the outfall, the pollutant must pass through any cross section at a rate equal to the rate of discharge. Thus, X cx= C0 r= co 0 v*x\ ss VSo \S= j - 1" Lo , Ss-Sx VSo = £ (VI-27) where Sv, Cv and fv denote downstream cross-sectional values A A A . and S0, C0 and f0 denote the cross-sectional vaues at the discharge point (or segment into which discharge is made). Upstream of the outfall, the quantity of pollutant diffused and advectively carried upstream is balanced by that carried downstream by the nontidal flow so that the net pollutant transport through any cross section is zero. Thus, the pollutant distribution is directly proportional to salinity distribution and (Dyer, 1973): C = C — x o s (VI-28) o Downstream of the outfall, the pollutant concentration resulting from a point discharge is directly proportional to river-borne pollutant concentration. Upstream from the discharge point, it is inversely proportional to river-borne pollutant concentrations. Figure VI-19 is a 264 ------- DISTANCE FROM HEAD_x_ L* 'L = Total Estuanne Length FIGURE VI-19 POLLUTANT CONCENTRATION FROM AN ESTUARINE OUTFALL (AFTER KETCHUM, 1950) 265 ------- graph of f versus distance from the estuary head for a typical estuary. The A solid fx line is also a measure of pollutant concentration for all points downstream of a pollutant outfall (either discharge location A or B). The actual concentration (Cv) for any point is equal to this f value multiplied X X by Q /R which is a constant over all x. Upstream concentrations decrease from C0 in a manner proportional to upstream salinity reduction (see dotted lines). It is important to note how even a small downstream shift in discharge location creates a very significant reduction in upstream steady-state pollutant concentration. Table VI-10 shows a suggested format for tabulating pollutant concentrations by the fraction of freshwater method. EXAMPLE VI-6 Calculation of Conservative Pollutant Concentration for a Local Discharge This example will again utilize the eight-segment scheme devised for the Patuxent Estuary in Example VI-2. The objective is to predict the concentration distribution of total nitrogen in the estuary resulting from a discharge of 80,000 mgN/sec into segment 4. The first step is to determine the nitrogen concentration in segment 4. From Equation VI-26, QD (8xlO"mgN/secxl2.4 hrs/tidal cyclex3600 sec/hr)(0.46) c = JL f = _ _ _ 0 R ° 5.36xl05 mVtidal cycle 3065 mgN = = 3.065 mgN/1 m3 For segments 1-3, upstream from the discharge, nitrogen concentration is found by Equation VI-28, c. = c ii o SQ 266 ------- TABLE VI-10 SAMPLE CALCULATION FABLE FOR DISTRIBUTION OF A LOCALLY DISCHARGED CONSERVATIVE POLLUTANT BY THE FRACTION OF FRESHWATER METHOD From Table VI-3 Segment Number Segment Containing Discharge in UJ Fraction of Freshwater Mean Segment Salinity (ppt) Pollutant Concentrations* (mg/1) *Pollutant concentration =- f. C0 — , down estuary of the discharge o si CQ — , up estuary of the discharge o ------- For segment 1, = 0.8% SQ = S, = 5.8%0 CH = 3.065 mgN/1 so / Q g ------- TABLE VI-11 NITROGEN CONCENTRATION IN PATUXENT ESTUARY BASED ON LOCAL DISCHARGE Segment Number Fraction of Freshwater s. Mean Segment g— Salinity o z— Concentration o mgN/1 0.037 10.3 0.08 0.25 7 6 5 Discharge 4 3 2 1 0.112 0.19 0.29 0.46 0.69 0.83 0.93 9.5 8.7 7.6 5.8 3.3 1.8 0.8 - - - 1 0.57 0.31 0.14 0.24 0.41 0.63 1 - - _ 0.74 1.26 1.93 3.06 1.75 0.95 0.43 269 ------- The same procedure yields nitrogen concentrations in segments 6-8, also downstream of the discharge. Figure VI-20 below shows the nitrogen concentration distribution over the entire estuary. Note that the nearer a discharge is to the estuary's mouth, the greater the protection rendered the upstream reaches of the estuary. END OF EXAMPLE VI-6 6.4.3 Continuous Fl_cw_No_n-Conservative Pollutants Most pollutant discharges into estuaries have some components which behave non-conservatively. A number of processes mediate the removal of compounds from natural waters, among these: • sorption by benthic sediments on suspended matter • partitioning • decay (by photolysis or biologically mediated reactions) • biological uptake t precipitation • coagulation. The latter two processes are particularly significant in estuaries. Thus, in addition to dispersion and tidal mixing, a time-dependent component is incorporated when calculating the removal of non-conservative pollutants from estuarine waters. The concentrations of non-conservative pollutants are always lower than those of conservative pollutants (which have a decay rate of zero) for equal discharge concentrations. The results of the previous section for conservative constituents serve to set upper limits for 270 ------- 4.0-1 3.0- ro •—i ra ~ 2.0 H O) o z "cc ° 1.0- 10 20 30 I discharge 40 Distance above estuary mouth (1000's of meters) FIGURE VI-20 HYPOTHETICAL CONCENTRATION OF TOTAL NITROGEN IN PATUXENT ESTUARY ------- the concentration of non-conservative continuous flow pollutants. Thus, if plots similar to Figure VI-17 for river discharges and to Figure VI-19 for other direct discharges have been prepared for flow rates equal to that of the non-conservative pollutant under study, some reasonable approximations can be made for steady-state non-conservative pollutant concentrations without requiring additional data. Assuming a first order decay rate for the non-conservative constituent, its concentration is given by: = CQe"kt (VI-29) where C - pollutant concentration at time "t" C = initial pollutant concentration k = decay rate constant For conservative pollutants k = 0 and C = CQ under steady-state conditions. Decay rates are determined empirically and depend on a large number of variables. Typical decay rates for BOD and coliform bacteria are shown in Table VI-12. If data are not available for a particular estuary, the use of these average values will provide estimates. 272 ------- TABLE VI-12 TYPICAL VALUES FOR DECAY REACTION RATES 'k1* Source BOD Coliform Dyer, 1973 .578 Ketchem, 1955 .767 Chen and Orlob, 1975 .1 .5 Hydroscience, 1971 .05-.125 1-2 McGaughhey, 1968 .09 Harleman, 1971 .069 *k values for all reactions given on a per tidal cycle basis, 20°C. 273 ------- It should be noted that decay rates are dependent upon temperature. The values given assume a temperature of 20°C. Variations in k values for differing temperatures are given by Equation VI-30: k = k 0 9T"20° (VI-30) where k = decay rate at temperature T k?0 = decay rate at 20°C (as given in Table VI-12) and 0 = a constant (normally between 1.03 and 1.05). Thus an ambient temperature of 10 C would reduce a k value of 0.1 per tidal cycle to 0.074 for a 0 = 1.03. Decay effects can be compared to flushing effects by setting time equal to the flushing time and comparing the resulting decay to the known pollutant removal rate as a result of flushing. If kt in Equation VI-29 is less than 0.5 for t = Tf, decay processes reduce concentration by only about one-third over the flushing time. Here mixing and advective effects dominate and non-conservative decay plays a minor role. When kTf > 12 decay effects reduce a batch pollutant to 5 percent of its original concentration in less than one-fourth of the flushing time. In this case, decay processes are of paramount importance in determining steady-state concentrations. Between these extremes, both processes are active in removing a pollutant from the estuary with 3 < kTf < 4 being the range for approximately equal contributions to removal. Dyer (1973) analyzed the situation for which decay and tidal exchange are of equal magnitude for each estuarine segment. Knowing the conservative concentration, the non-conservative steady-state concentration in a segment is given by: 274 ------- i=l/..,n r. for segments downstream of the outfall (VI-31) and ' i o i = 1,.., n S r. T_ o \l-(l-r.)e for segments upstream /.., ~^\ -kt / of the outfall where C = non-conservative constituent mean concentration in segment "i" C = conservative constituent mean concentration in segment of discharge r. - the exchange ratio for segment "i" as defined by the modified tidal prism method n = number of segments away from the outfall (i.e. n=l for segments adjacent to the outfall; n-2 for segments next to these segments, etc.) and other parameters are as previously defined. In the case of a non-conservative pollutant entering from the river, n = 1, and the only concentration expression necessary is f. ,'nerf r. 1 (VI- 34) 275 ------- Table VI-13 shows a suggested format for tabulating pollution concentrations by the modified tidal prism method. EXAMPLE VI-7 Continuous Discharge of a Non-Conservative Pollutant into the Head of an Estuary The Fox Mill Run Estuary (see Example VI-3) is downstream of the Gloucester, Virginia, sewage treatment plant. Knowing the discharge rate of CBOD in the plant effluent, the purpose of this example is to determine the concentration of CBOD throughout the estuary. It is first necessary to determine the concentration of CBOD in Fox Mill Run as it enters the estuary (assume no CBOD decay within the river). The following information has been collected: C , Background CBOD in river = 3 mg/1 Q , River flow below treatment plant discharge - 0.031 m3/sec Q ,, Treatment plant discharge rate = 0.006 m3/sec Cd, Treatment plant effluent CBOD = 45 mg/1 The CBOD concentration in the river downstream of the treatment plant is found using the equation: C (Q -Q.) + C.Q, rwr xd'  ------- TABLE VI-13 SAMPLE CALCULATION TABLE FOR DISTRIBUTION OF A LOCALLY DISCHARGED NON-CONSERVATIVE POLLUTANT BY THE MODIFIED TIDAL PRISM METHOD From Table VI -6 Segment Number Distance of Center Above Mouth (m) Segment Exchange Ratio r . Mean Salinity (from salinity plot) Si PPt Fraction of River Water f - S- 1 1 Ss B, 1 Pollutant Concentration i-1 n (mg/1) ------- To find the CBOD concentration distribution in the estuary, the following additional data are used: S$, Chesapeake Bay salinity = 19.0 °/oo (at the mouth of Fox Mill Run Estuary) k, CBOD decay constant = 0.3/day T, Tidal cycle = 12.4 hours so kt = 0.3/day x 12.4 hr x 1 day/24 hours = 0.155 Also necessary are mean salinity values for each estuary segment. Values for the Fox Mill Run Estuary are summarized in Table VI-14. Fraction of freshwater values for each segment are found using the formula: where the variables are as previously defined. Next, values of the coefficient B. must be calculated for each segment "i". For segment 0, TO, the segment exchange ratio, = 0.74 and - rO = _ 0.^4 _ = o 95 B° = l-(l-r0)e-kt = l-(l-0.74)e-°-155 = Coefficient values for all segments are compiled in Table VI-14. 278 ------- "vj UD TABLE VI-14 SALINITY AND CBOD CALCULATIONS FOR FOX MILL RUN ESTUARY 1 ' From Problem VI -3 i Center Point i Distance Above i Est. Mouth, | Segment Number Meters | 1 River \ (>3200) 0 2950 i 2470 j I 2 i 1945 3 915 i . - _. . 1 i Exchange Ratio For Segment _ 0.74 0.71 0.56 0.71 Mean Segment Sal ini ty Si , ppt (From Sal . Plot) -0 4.7 8.6 11.6 15.3 Fraction of Fresh (River) fi Ss (Ss= 19.0) 1.00 0.75 0.55 0.39 0.19 BT - 0.95 0.94 0.90 0.94 i i Concentration of I CBODU r -r . n Ci Ci-l fM Ci ' (mg/1 ) : i i 11.1 j 8.1 ! i 5.5 j 3.6 1.6 i ------- Finally, CBOD concentrations for the individual segment are calculated, beginning with the uppermost segment and working downstream. The concentration in segment "i" is found by: f. For segment 0, the river is taken as segment "i-1", and the calculation is as follows: CQ = 11.13 mg/1 ( ~J 0.95 - 8.1 mg/1 For segment 1, /.55 \ Ci = 8.1 mg/1 I—- I 0.94 = 5.6 mg/1 and so on. Figure VI-21 depicts this estimate of the distribution of CBOD in the estuary. In addition, hypothetical concentrations of a conservative pollutant (k = 0) and coliform bacteria (k = 1.0) are plotted. Downstream concentration diminishes faster for substances having larger decay constants, as might be expected. END OF EXAMPLE VI-7 6.4.4 Multiple Waste Load Parameter Analysis The preceding analysis allowed calculation of the longitudinal distribution of a pollutant, either conservative or non-conservative, resulting from a single waste discharge. However, the planner will probably want to simultaneously assess both conservative and non-conservative elements from several separate discharges. This can be accomplished by graphing all desired single element distributions on one graph showing concentration 280 ------- 182 Relative Concentration Units co cn i hO ~n PO o rn x i- I- < r~ m ^o cr) c rn GO O :z: (/> o rri m > 2: CO m "2. m i—i z CD X m a CO O CD cr o CD o c 3" g m en c 0) O q w" 3 CO *-*• CD -^ CO CO O CO o cn ------- versus length of the estuary. Once graphed, the resulting concentration may be linearly added to obtain a total waste load. The pollutant concentration increment from each source is calculated by assuming the source is the sole contribution of pollution (i.e. other waste loadings are temporarily set equal to zero). This method, called superposition, is valid as the long as volumetric discharge from any of the sources does not signicantly influence the salinity distribution within the estuary. This assumption is typically true, unless the estuary is extremely small and poorly flushed, and the volumetric discharge is large relative to tidal and advective flushing components. An example of the superposition procedure is shown in Figure VI-22. Three local point sources of pollutants discharge at locations A, B, and C. A background source enters the estuary with the river discharge. The contribution due to each source can be found from the fraction of freshwater method (assuming the pollutants act conservatively) as follows: -Ji f R fX x > 0, where x is measured from the head of the estuary CA=^ R x Wn S. x B R x W S T fs T ' * < B wc T fx ' R C R * 282 ------- 00 CO CD C 70 m POLLUTANT CONCENTRATION a < m m o o "O r~ m CO m ET o a i—i -i o CO oHead g o m o i m > o Mouth ------- where C = concentration due to river discharge b C , C , C = concentrations due to sources A, B, and C, M D \j respectively R = river flow rate fn > fp,> fr = fraction of freshwater at locations A, B, C, ABC respectively S., SB, Sc = salinity at locations A, B, and C, respectively. The pollutant concentration (above background) at any location in the estuary is: Sum = CA+CB+CC and is shown in Figure VI-22. When this is added to the background level, the total pollutant concentration becomes: CT = (WV + Cb The dotted line in Figure VI-22 depicts CT< The technique of graphing outfall location and characteristics with resulting estuarine pollutant concentration can be done for all anticipated discharges. This will provide the planner with a good perspective on the source of potential water quality problems. Where the same segmentation scheme has been used to define incremental pollutant distributions resulting from several sources, the results need not even be plotted to determine the total resultant concentrations. In this case, the estuary is evaluated on a segment-by-segment basis. The total pollutant concentration in each segment is calculated as the arithmetic sum of the concentration increments resulting from the various sources. 284 ------- EXAMPLE VI-8 The previous two example problems involved calculations of nitrogen concentration in the Patuxent Estuary resulting from individual nitrogen sources. The objective of this example is to find the total nitrogen concentration in the estuary resulting from both nitrogen sources. The eight-segment scheme of Examples VI-6 and VI-7 is retained for this problem. For each segment, the incremental nitrogen increases are summed to give the total concentration: C = Cb + CA where C, is the concentration resulting from the N source discharging into the estuary at point A For segment 1, the calculation is: C = 1-75 mg/1 (from river) + 0.43 mg/1 (from local source) = 2.18 mg/1 total nitrogen Necessary data and final concentrations for each segment are shown in Table VI-15. END OF EXAMPLE VI-8 6,4.5 ^sj)ersj[oji-A^dvection Equations for Predicting _P_o_llutant_l^sjtrj_bjjtj_ons Dispersion-advection equations offer an attractive method, at least theoretically, of predicting pollutant and dissolved oxygen concentrations in estuaries. However, from the point of view of hand calculation, the advection-dispersion equations are usually tedious to solve, and therefore mistakes can unknowingly be incorporated into the calculations. Dispersion-advection equations have been developed in a variety of forms, including one-, two-, and three-dimensional representations. The equations in this section are limited to one-dimensional representations in 285 ------- TABLE VI-15 DISTRIBUTION OF TOTAL NITROGEN IN THE PATUXENT ESTUARY DUE TO TWO SOURCES OF NITROGEN Segment Number 8 7 6 5 4 3 2 1 River Results From Problem VI-4 Total Nitrogen From River mgN/1, Cfa 0.07 0.21 0.36 0.55 0.80 1.30 1.56 1.75 1.88 Results From Problem VI-5 Total Nitrogen From Point A Source (Segment 4) mgN/1, CA 0.25 0.74 1.26 1.93 3.06 1.74 0.95 0.43 0.00 Resultant Concentration c=cb + CA mgfl/1 0.32 0.95 1.62 2.48 3.92 3.04 2.51 2.18 1.88 285 ------- order to reduce the amount of data and calculations required. One-dimensional dispersion-advection equations can be expressed in quite divergent forms, depending on boundary conditions, cross-sectional area variation over distance, and source-sink terms. O'Connor (1965), for example, developed a variety of one-dimensional advection-dispersion equations for pollutant and dissolved oxygen analyses in estuaries, some of which are infeasible for use on the hand-calculation level. The advection-dispersion equations to be presented subsequently in this chapter can be used to predict: • distributions of conservative or non-conservative pollutants, t pollutant distributions in embayments, and • dissolved oxygen concentrations. Solutions from advection-dispersion can be superposed to account for multiple discharges. Example VI-9, to be presented subsequently, will illustrate this process. As the name of the equations implies, dispersion coefficients are needed in order to solve advection-dispersion equations. Tidally averaged dispersion coefficients are required for the steady-state formulations used here. The tidally averaged dispersion coefficient (EL) can be estimated from the following expression: E = ___ (VI-35) L A dS/dx (VI-36) 287 ------- where S = tidally and cross sectionally averaged salinity in vicinity of discharge 2Ax = distance between the salinity measurements Sx+Ax (at a distance Ax down estuary) and SX_AX (at a distance Ax up estuary) R = freshwater flow rate in vicinity of discharge The distance interval 2Ax should be chosen so that no tributaries are contained within the interval. In the absence of site specific data, the dispersion coefficients shown in Tables VI-16 and VI-17 can provide estimates of dispersion coefficients. For pollutants which decay according to first order decay kinetics, the steady state mass balance equation describing their distribution is: E ££ _ UdC . kc __ (VI.37) L dx* dx The solution to Equation VI-37 is: C e J2X x > 0(down estuary) (VI-38a) CeJlX x<0(up estuary) o where 2AEL 2AEL 288 ------- TABLE VI-16 TIDALLY AVERAGED DISPERSION COEFFICIENTS FOR SELECTED ESTUARIES (FROM HYDROSCIENCE, 1971) 00 UD Estuary Delaware River Hudson River (N.Y.) East River (N.Y.) Cooper River (S.C.) Savannah R. (Ga. , S.C.) Lower Raritan R. (N.J.) South River (N.J.) Houston Ship Channel (Texas) Cape Fear River (N.C.) Potomac River (Va. ) Compton Creek (N.J. ) Wappinger and Fishkill Creek (N.Y.) Freshwater Inflow (cfs) 2,500 5,000 0 10,000 7,000 150 23 900 1,000 550 10 2 Low Flow Net Non tidal Veloci ty ( fps) Ik- dd - Mouth 0.12-0.009 0.037 0.0 0.25 0.7-0.17 0.047-0.029 0.01 0.05 0 .48-0.03 0.006-0.0003 0.01-0.013 0.004-0.001 Disiiorbio i Coef f i c iuii t (iin^/diiy ) 5 20 H) 30 10-20 5 5 27 2-10 1-10 1 0.5-1 *1 mi2/day = 322.67 ft2/sec ------- TABLE VI-17 TIDALLY AVERAGED DISPERSION COEFFICIENTS (FROM OFFICER, 1976) Estuary Dispersion Coefficient Range (ft2/sec) Comments San Francisco Bay Southern Arm Northern Arm Hudson River fiarrows of Mercey Potomac River Severn Estuary 200-2,000 500-20,000 4,800-16,000 1 ,430-4,000 65-650 75-750 (by Stommel) 580-1,870 (Bowcien) Measurements were made at slack water over a period of one to a few days. The fraction of freshwater method was used. Measurements were taken over three tidal cycles at 25 locations. The dispersion coefficient was derived by assuming E|_ to be constant for the reach studied, and that it varied only with flow. A good relationship resulted between E. and flow, substantiating the assumption. The fraction of freshwater method was used by taking mean values of salinity over a tidal cycle at different cross sections. The dispersion coefficient was found to be a function of dis- tance below the Chain Bridge. Both salinity distribution studies (using the fraction of freshwater method) and dye release studies were used to detemi ne E. . Bowden recalculated |_ values originally determined by Stoiuiuel , who had used the fraction of freshwater method. Bowden included the fresh- water inflows from tributaries, which produced the larger estimates of E. - 290 ------- TABLE VI-17 (continued) Estuary Tay Estuary Dispersion Coefficient Range (ft2/sec) 530-1,600 Comments The fraction of freshwater (up estuary) method was used. At a given 1,600-7,500 location, EL was found to vary (down estuary) with freshwater inflow rate. Thames Estuary 600-1,000 Calculations were performed (low flow) using the fraction of fresh- 3,600 water method, between 10 and (high flow) 30 miles below London Bridge. Yaquina Estuary 650-9,200 The dispersion coefficients for (high flow) high flow conditions were sub- 140-1,060 stantially higher than for low (low flow) flow conditions, at the same locations. The fraction of freshwater method was used. 291 ------- U = net velocity k = decay rate W = discharge rate of pollutant (at x=0) For Equations VI-38a and VI-38b to accurately estimate the pollutant distribution in an estuary, the cross-sectional area of the estuary should be fairly constant over distance, and the estuary should be relatively long. For screening purposes the first constraint can be met by choosing a cross-sectional area representative of the length of estuary being investigated. If the estuary is very short, however, pollutants might be washed out of the estuary fast enough to prevent attainment of a steady-state distribution assumed by Equations VI-38a and VI-38b. For shorter estuaries the fraction of freshwater method, modified tidal prism method, or near field approach are more appropriate. At times when the freshwater flow rate in an estuary is essentially zero pollutant concentrations might increase to substantial levels, if tidal flushing is small. Under these conditions the mass-balance expression for a pollutant obeying first order kinetics is: E. d2C - kc = 0 L "377"? (VI-39) The solution to this equation is: C = for x > 0 (down estuary) (VI-40a) for x <0 (up estuary) (VI-40b) where (VI-41) 292 ------- When the pollutant is conservative (i.e. k=0), Equation (VI-39) reduces to: The solution is: CQ , x < 0 (up estuary) (VI-43a) W c = I (L-x) + C , x > 0 (down estuary) (VI-43b) where WL C . = C. + 0 L ELA C. = background concentration of the pollutant at the mouth of the estuary L = distance from the discharge location to the mouth of the estuary. Equation VI-43 illustrates the important concept that the concentrations of conservative pollutants are constant up estuary from the discharge location (when the river discharge is negligible) and decrease linearly from the discharge point to the mouth of the estuary. Equations VI-40 and VI-43 apply to estuaries of constant, or approximately constant, cross-sectional area (e.g. sl.oughs). If the cross-sectional area increases rapidly with distance toward the mouth, the methods presented in Section 6.5 are more appropriate. The dissolved oxygen deficit equation (where deficit is defined as the difference between the saturation concentration and the actual dissolved oxygen concentration) for one-dimensional estuaries at steady-state conditions is: I'dD . E d2D dx dx' 293 ------- where D = dissolved oxygen deficit L = BOD concentration k2 = reaeration rate k = BOD decay rate Using Equation VI-38 to represent the BOD distribution, the expression for the deficit D is: D = — kW A(k,-k) exp 2 E, _- -- x \ exp 2 C, (VI-45) where The plus (+) sign is used to predict concentrations up estuary (x<0) The minus (-) sign is used to predict concentrations down estuary (x>0) = 2 = U2 + 4kE = 2 = U2 + 4k2E, M = mass flux of dissolved oxygen contained in the discharge 294 ------- The advantage of expressing the dissolved oxygen concentration in terms of the deficit is that the principle of superposition can be invoked for multiple discharges within a single estuary. Specifically D = Z D. and C = Cs - Z Di (VI-47) where D- = dissolved oxygen deficit resulting from the i^L discharge C = final dissolved oxygen concentration C = dissolved oxygen saturation level. Figure VI-23 shows the relationship between dissolved oxygen saturation and temperature and salinity. EXAMPLE VI-9 Dissolved Oxygen Concentration Resulting from Two Sources of BOD Two municipal wastewater treatment plants discharge significant quantities of BOD into the James River in Virginia. One discharges near Hopewell, and the second 10 miles further down estuary, near Uest Point. Calculate the dissolved oxygen concentration in the estuary as a function of distance. Pertinent data are: 295 ------- CD C 70 IT] IND i^O CPl en — l en m o 2 I- -D < m m 73 O C X pa < m o m > z •z. O 00 > CO H > C -< c: 2: o OXYGEN SATURATION CONCENTRATION (mg/l) ------- • BOD5 in Hopewell plant effluent = 69,000 Ibs/day t BOD in West Point plant effluent, located 10 miles downstream from Hopewell = 175,000 Ibs/day • freshwater flow rate = 2,900 cfs • dissolved oxygen saturation = 8.2 mg/1 • cross sectional area = 20,000 ft2 • reaeration rate = 0.2/day • deoxygenation rate = 0.3/day • dispersion coefficient = 12.5 mi2/day • effluent dissolved oxygen = 0.0 mg/1. The dissolved oxygen deficit due to each of the two contributions can be determined independently of the other using Equation IV-45. The results are plotted in Figure VI-24. The deficits are added to produce the total deficit (0(x)) due to both discharges (Figure VI-24a). The distance scale in Figure VI-24a is referenced to the Hopewell plant. The West Point plant is placed at mile 10. When the deficit at this location due to the West Point plant is calculated, set x = 0 in Equation VI-45. The dissolved oxygen concentration then becomes C(x) = 8.2-D(x), and is shown in Figure VI-24b. One example calculation of dissolved oxygen deficit will be shown to illustrate the process. Consider the deficit produced at mile 0.0, due to the Hopewell plant. The waste loading from the Hopewell plant is: 69,000 x 1.46 = 100,000 Ibs/day, BOD-ultimate =1.16 Ibs/sec 297 ------- Dissolved Oxygen Concentration, mg/l Dissolved Oxygen Deficit, mg/l 00 CD c: xi m i ro -Cr m c_ a > — • 2 O m H co m m co XI CO O m O O X m ~a XI o o- (D cn CD ^^ O a- 5 I ro o o •a (D CD cn O" CO b i i i i t 03 b i CD 0) CD G>_ O o •a CD CD -j. !\3 w -C». cn cn -^ b b b b b b b I i i I 1 I I cn I o CD-»O- $CD I cn r»o- cn o' HOD O 03 CD D. CD §• c CD CD <—*• <-*- o o if o cn ^3 -<• CD ------- When x = 0 Equation VI-45 simplifies to: D = kW _ _ A(k2-k) \\fa7 _! ___ L so so Ql = U2 + 4k E / 2900 \2 i — i -f- L \20000/ 4(.3)(12.5)(5280)(5280) 81400 • 86400 = .077 ft2 sec' \TaT = .278 ft/sec 2 lr.n~2 'a2 = U2 + 4k2EL = 0.058 ft2/sec = .242 ft/sec The deficit is: D = (.3)(1.16) 20000(.2-,3) ' 1 . .278 1 - .242 = 9.3 x ID'5 lb/ft3 = 1.5 mg/1 This value is then plotted in Figure VI-24 at mile point 0.0. The deficit at this location due to West Point is evaluated at x = -10 miles in Equation VI-45, since West Point is located 10 miles down estuary of Hopewell. A deficit of 0.6 mg/1 is found, and is plotted in Figure VI-24 at mile point 0.0. The total deficit at Hopewell is 1.5 +0.6 = 2.1 mg/1, as shown in the figure. END OF EXAMPLE VI-9 299 ------- 6.4.6 Pritcnard's Two-dimensional Box Model for Stratified Estuaries Many estuaries in the United States are either stratified or partially mixed. Because the circulation of stratified systems is fairly complex, few hand calculation methods are available for their analysis. Instead computerized solutions are generally used. One method developed by Pritchard (1969) which predicts the distribution of pollutants in partially mixed or stratified estuaries is suitable for hand calculations provided the user does not require too much spatial resolution. This method, called the "two-dimensional box model", divides the estuary horizontally from head to mouth into a series of longitudinal segments. Each segment is divided into a surface layer and a bottom layer. The analysis results in a system of n simultaneous linear equations with n unknowns, where n equals twice the number of horizontal segments. The unknowns are the pollutant concentrations in each layer. Division of the estuary into only two horizontal segments results in four simultaneous equations, which is probably the most one would like to solve entirely by hand. However, many programmable hand calculators contain library routines for solving systems of 10 or more simultaneous equations, which would allow the estuary to be divided into 5 or more horizontal segments. If many more segments are desired, the solution could be easily implemented on a computer using a numerical technique such as Gaussian elimination to solve the resulting system of simultaneous linear equations. The following information is required for the two-dimensional box analysis: 1) the freshwater flow rate due to the river; 2) the pollutant mass loading rates; and 3) the longitudinal salinity profiles along the length of the estuary in the upper and lower layers, and the salinity at the boundary between these two layers. The upper layer represents the portion of the water column having a net nontidal flow directed seaward, and the lower layer represents the portion of the water column having net nontidal flow directed up the estuary. If no velocity data are available, these layers can generally be estimated based on the vertical salinity profiles. 300 ------- Figure VI-25 shows the parameters used in the analysis, which are defined as follows: n = segment number, increasing from head toward mouth (S ) = salinity in upper layer of segment n (S ) - salinity in lower layer of segment n (S ) - salinity at the boundary between the upper and lower layers of segment n (S ) , = salinity in the upper layer at the boundary between u n~15 n segments n-1 and n (S ) = sal-inity in the lower layer at the boundary between i n** x 5 '' segments n-1 and n (Q ) , = net nontidal flow rate in the upper layer from u n— i, n segment n-1 to n (Q ) , = net nontidal flow rate in the lower layer from i n, n-1 segment n to n-1 (Qv)n = net upward vertical flow from the lower to the upper layer of segment n E = vertical exchange coefficient between the lower and upper layers of segment n R - freshwater flow rate due to river (qu)n = pollutant mass loading rate to upper layer of segment n (from external sources) 301 ------- o ro n-1 n + 1 >u'n-1,n (Qu>n-1,n u - — - (Su)n (Cu)n (Qu)n, .*.'•"• >:i.'"!<.": a'•/••*'i?'!V"V'-?V'";V-1 • ":•;• •^-•'''•''^.;:'''>>"';'-;<'-'.-''-'>'.;:;'-"'t;':^' VJ?'' '.V-';«-v'»'.'.''/1X.' -V-'^-o•'.••.«.•,•.•. •'•V;''-X'-\'v\'-'V.:';''-»A\-V':X:-i-%>':'';-:'^\:;«:^V;p^V/o;\ FIGURE V 1-2:5 DEFINITION SKETCH FOR PRITCHARD'S TWO-DIMENSIONAL Box MODEL ------- (qJri = Pollutant mass loading rate to lower layer of segment n (from external sources) (C ) = pollutant concentration in the upper layer of segment u n n (C1)n = pollutant concentration in the lower layer of segment n Pritchard's two-dimensional box analysis as presented here requires the following assumptions: 1. steady-state salinity distribution 2. the pollutant is conservative 3. the concentration of the pollutant is uniform within each layer of each segment and 4. the pollutant concentration at the boundary between segments or layers is equal to the average of the concentrations in the two adjacent segments or layers. Application of the two-dimensional box model involves six steps. These are: 1. Plot the longitudinal salinity profiles in the upper and lower layers, and at the interface between the two layers. If information on the net nontidal velocity distribution is not available to define the layers, the boundary may be estimated for a given section of the estuary as the depth at which the vertical salinity gradient is maximum. The resulting plots will be used to determine the average salinities in each segment and layer, and the salinities at the boundaries between each segment and layer. 303 ------- 2. Segment the estuary. The number of segments will depend on the degree of spatial resolution desired, and the limitations of the hand calculators used to solve the system of simultaneous equations. The accuracy of the results will generally increase with the number of segments used, since the assumptions of the analysis are better satisfied. A minimum of three horizontal segments should probably be used to obtain even a rough estimate of the pollutant distribution in the estuary. This will require the solution of six equations and six unknowns. 3. Compute the net nontidal flows in the upper layer and lower layer at the boundary between each horizontal segment using Knudson's Hydrographical Theorem (Dyer, 1973): l, n (n ) , = R -—- (VI-48) n-l, n 'n. n-1 (S ) , -(S ) , (VI-49) v i'n-1, n v u n-1, n At the upstream freshwater boundary of the estuary, «>'>„. n-1- °" 4. Compute the net upward vertical flows between layers for each segment using the continuity equation for the upper layer of the seginent: = (Qu}n, n+1 " ^n-l, n (vi-50) ------- 5. Compute the vertical exchange coefficients between layers for each segment using the salinity balance equation for the upper layer of the segment, which can be arranged in the following form: Vn. n+1 ------- Since most pollutant discharges are buoyant, they should be considered as loadings to the upper layer, even though they may be physically introduced at the bottom. Pollutants which are denser than the upper waters and which would sink to the bottom should be considered as loadings to the lower layer. However, the analysis is not applicable to pollutants which tend to remain near the bottom and accumulate in or react with the bottom sediments. The above mass balance equations can be simplified and rearranged into the following form: 2En+ (Vn| '-,'„ -, (VI-54) [-n n] (VI-55) for the lower layer of segment n. This pair of equations is written for each segment, resulting in a system of simultaneous equations where the concentrations, (Cu)n and (Ci)n, are the unknowns, the terms enclosed in square brackets are the coefficients, and the terms on the right hand side of the equations are the constants. However, since each equation involves both the uptream and downstream segments for a given layer, the boundary conditions at both the upstream and downstream end of the estuary must be applied so that there will not be more 306 ------- unknowns than equations. At the upstream end of the estuary, the following boundary conditions apply: (Qu)n_l5 n = R = river flow rate (C ) T = CD - pollutant in river u n-i K (Q ) , =0 (no salt water movement upstream into the river) These conditions simplify the previous equations to u\ + [2E. + i + R = ~z (VI-56) for the upper layer of the first upstream segment and [2E< - (Qyh] (cu), + [-2E,] (cj, + [(QA.J (c,)2 -2(qi)i (vi-57) for the lower layer of the first upstream segment. For the lower layer of the last downstream segment at the ocean end of the estuary, the following boundary condition is used to simplify the equation: (Cj = 0 (no pollutant, entering the lower layer from the ocean waters outside the mouth of estuary) which simplifies the corresponding equation to: n. n-l] K.Jn-l +[2En ' < Vn For the upper layer of the last segment at the mouth of the estuary, some assumption must be made about the pollutant concentration in the upper layer just outside the mouth to eliminate the (n+1) term from the equation. If actual data 307 ------- are available based on field measurements, a measured value of (C ) +, can be used. This simplifies the corresponding equation to: >n-l. n] n-l + ['2En] (Cu>n + [ 2En + <«v>n] ^n = ~2^n + „-! ' ['2En ' 'c <«„>„. n+l ] n + [«„ * (Qv)n] (C, )„ = -2(qu)n Step (6) of the two-dimensional box analysis involves computing all of the coefficients and constants in the system of equations defining each segment and layer (equations VI-54 and VI-55) and applying the boundary conditions to produce equations for the first upstream and last downstream segments in the estuary (equations VI-56 through VI-60). The coefficients and constants are functions of the variables previously computed in steps (3) through (5). The resulting equations are then solved using library routines in programmable hand calculators, or by programming an appropriate numerical technique such as Gaussian elimination on either a programmable hand calculator or a computer. 308 ------- Since the analysis requires application of the boundary conditions at the freshwater head of the estuary and the coastal mouth of the estuary to obtain the same number of equations as unknowns, the entire estuary must be included in the first cut analysis. The initial analysis will yield the overall pollutant distribution throughout the entire estuary. Once this is determined, the analysis could be repeated to obtain more detail for smaller portions of the estuary by using the first cut results to estimate the pollutant boundary conditions at each end of the region of concern, and then rearranging equations (7) and (8) so the terms involving the concentrations outside the specified regions are treated as constants and moved to the right hand side of the equations. The Pritchard Model theoretically allows external pollutant loading to be introduced directly into any segment along the estuary. By moving external loadings from the head to near the mouth of the estuary, the planner can predict how pollutant levels are affected. However, experience with the model has shown that when external side loadings are considerably larger than those which enter at the head of the estuary, model instabilities can arise. When this occurs, the pollutant profile oscillates from segment to segment, and negative concentrations can result. It is recommended that the user first run the Pritchard Model by putting all pollutant loading into the head of the estuary. This situation appears to be always stable, and, as the following example shows, reasonable pollutant profiles are predicted. EXAMPLE VI-10 Pollutant Distribution in a Stratified Estuary The Patuxant River in Maryland is a partially stratified estuary, where the degree of stratification depends on the freshwater flow rate discharged at the head of the estuary. Table VI-18 shows the salinity distribution within the estuary under low flow conditions for each segment and layer. The location of each layer is shown in Figure VI-26. Also shown in the table is the pollutant distribution by layer and segment for a mass flux of 125 Ibs/day (57 kg/day) of 309 ------- TABLE VI-18 SALINITY AND POLLUTANT DISTRIBUTION IN PATUXENT ESTUARY UNDER LOW FLOW CONDITIONS Segment Number 1 2 3 4 5 6 7 8 9 10 11 12 boundary Salinity (as Chloride, mg/1) Upper Layer Lower Layer 496. 1831. 3771. 6050. 8040. 9310 10010. 10790. 11240. 11830. 12100. 12750. 13500. 524. 1940. 3970. 6280. 8220. 9910. 10660. 11070. 11760. 12120. 12650. 12850. 13500. Pollutant Upper Layer 0.193 0.173 0.144 0.100 0.081 0.062 0.051 0.040 0.033 0.025. 0.021 0.011 0.0 Concentration (mg/1) Lower Layer 0.192 0.171 0.141 0.108 0.078 0.053 0.042 0.036 0.025 0.020 0.013 0.009 0.0 310 ------- FIGURE VI-26 PATUXENT ESTUARY MODEL SEGMENTATION 311 ------- conservative pollutant input at the head of the estuary. The pollutant distribution was predicted by solving on a computer the 12-segment, 2-layer system (24 simultaneous equations). The salinity distribution shown in Table VI-18 was used as input data. As a point of interest, the same network was solved using the model WASP (courtesy of Robert Ambrose, ERL, U.S. Environmental Protection Agency, Athens, Georgia), which is a dynamic two-dimensional estuary model. Instead of using salinity directly, UASP predicts the salinity distribution based on dispersive and advective exchange rates. The salinity distribution predicted by WASP is the same as shown in Table VI-18, which was used as input to Pritchard's Model. After running WASP to steady-state conditions, the pollutant distribution throughout the estuary was virtually the same as predicted by Pritchard's Model. The pollutant distribution in the Patuxant estuary will be solved in detail using 4 segments instead of 12. The resulting system of 8 simultaneous equations can be solved on a variety of hand-held calculations. The tabulations below show salinities at each segment boundary, and the horizontal flow rates in the upper and lower layers. Boundary (Vn-l,n n-l,n mg/l-Cl 0, 1 1, 2 2, 3 3, 4 4, 5 *This 0.0 4960. 9420. 11445. 13500. is the specified mg/l-Cl 0.0 5080. 9640. 11860. 13500. river inflow «Un-l,n mVsec 3.3* 116.7 139.5 94.3 156.8 rate, R. (Q, ) , m3/sec 0.0 113.4 136.2 91.0 153.5 The flow rates were calculated from Equations VI-48 and VI-49, while the salinities were found directly from Table VI-18. 312 ------- The salinities within each layer, the salinity and flow rate between the interface of each layer, and the exchange coefficients are tabulated below. Segment n 1 2 3 4 (Su>n mg/l-Cl 1830 8040 10790 12100 n mg/l-Cl 1890 8130 10930 12380 (S])n mg/l-Cl 1940 8220 11070 12650 (Qv)n m3/sec 113. 23. -45. 63. En m 3/sec 3260. 3140. 930 280. The flow rates were found from Equation VI-50, and the exchange coefficients from Equation VI-51. Substituting these data into the pollutant mass balance expressions (Equations VI-54 through VI-59), the following system of equations result: -6523. 6638. -117. 0. 0. 0. 0. 0.~ 6411. -6525. 0.0 113. 0. 0. 0. 0. 117. 0.0 -6275. 6297. -139. 0. 0. 0. 0. -113. 6252. -6275. 0.0 136 0. 0. 0. 0. 139. 0.0 -1856. 1811. -94. 0. 0. 0. 0. -136. 1901 -1S56. 0.0 91. 0. 0. 0. 0. 94. 0.0 -561 624. 0. 0. 0. 0. 0. -91. 499. -561 f(C T (c,) (C )' U 2 i " •" -1.32" 0. 0. 0. 0. 0. 0. 0. The value -1.32 in the first row of the right-hand side column vector is twice the loading of pollutant which comes into the upper layer of the "first segment, as required in Equation VI-56. The units are in gm/sec to be compatible with the units of the remaining terms in the equations: so M = 125 Ibs/day = 0.66 gm/sec 21-1 = 250 Ibs/day =1.32 gm/sec 313 ------- The pollutant distribution which results from solving the eight linear equations is: (Cu)i = (0.17) (C-,)i = (0.17) (Cu)2 = (0.08) (Ci)2 = (0.08) (Cu)3 = (0.04) (C})3 = (0.04) (CUK = (0.02) (c1)4 = (o.oi) These values are nearly the same as found when 12 segments were used, which indicates 4 segments are sufficient to accurately predict pollutant distribution for this problem. END OF EXAMPLE VI-10 6.5 POLLUTANT DISTRIBUTION FOLLOWING DISCHARGE FROM A MARINE OUTFALL 6.5.1 Introduction Numerous coastal states have enacted water quality standards which limit the maximum allowable concentration of pollutants, particularly metals and organic toxicants, which can be discharged into estuarine and coastal waters. The standards normally permit that an exempt area, called a mixing zone, be defined around the outfall where water quality standards are not applicable. For example, the Water Quality Control Plan for Ocean Waters of California (State Water Resources Control Board, 1978) sets forth the following statement directed at toxic substance limitations: "Effluent limitations shall be imposed in a manner prescribed by the State Board such that the concentrations set forth ... as water quality objectives, shall not be exceeded in the receiving water upon 314 ------- the completion of initial dilution." The mixing zone, or zone of initial dilution (ZID), is non-rigorously defined as the volume of water where the wastewater and ambient saline water mix during the first few minutes following discharge, when the plume still has momentum and buoyancy. As the wastewater is discharged, it normally begins to rise because of its buoyancy and momentum, as illustrated in Figure VI-27. If the ambient water column is stratified and the water depth is great enough, the rising plume will not reach the surface of the water, but rather will stop at the level where the densities of the plume and receiving water become equal. This level is called the plume's trapping level. (See Figure VI-27.) Due to residual momentum, the plume might continue to rise beyond the trapping level, but will tend to fall back after the momentum is completely dissipated. Once the plume stops rising, the waste field begins to drift away from the ZID with the ambient currents. At this time, initial dilution is considered complete. Section 6.5.2, which follows, shows how initial dilution is calculated, and then Sections 6.5.3 and 6.5.4 illustrate how pollutant concentrations at the completion of initial dilution can be predicted. Sections 6.5.5 and 6.5.6 explain methods of predicting pollutant and dissolved oxygen concentrations, respectively, as the waste field migrates away from the ZID. The methods presented in section 6.5.2 through 6.5.6 are applicable to stratified or non-stratified estuaries, ernbayments, and coastal waters. The methods assume that reentrainment of previously discharged effluent back into the ZID is negligible. Reentrainment can occur if the wastewater is discharged into a confined area where free circulation is impaired or because of tidal reversals in narrow estuaries. 315 ------- Participates (which settle out of drift field) Effluent leaving diffuser ports *. '.« *'•.•'.'„'*-''- o •'-'• '•"•'••a •"."•">'', o'.'- :.''-*'°-'.''"_'.' •' - ".•,;'• • '.'-o '.••-*•.' • •*.'«•'•".•' '••» '••'.'•'.- •'.'• ••-. „., •••. ' . .'' .• "A « • '• .",•.'••-••,'-°- ••' .'• '•'• ;• . •*•-.'-.-• r •• - .'•?.-•()•.•••.•»?;.'.•.'•'•'•.•*•" •'•V'"*"» FIGURE VI-27 WASTE FIELD GENERATED BY MARINE OUTFALL 316 ------- 6.5.2 Prediction of Initial Dilution 6.5.2.1 General Discharge to bodies of water through submerged diffusers is a common waste water management technique. A diffuser is typically a pipe with discharge ports spaced at regular intervals. Such discharges are often buoyant with high exit velocity relative to the ambient velocity. The resulting waste streams act as plumes or buoyant jets. The velocity shear between ambient and plume fluids results in the incorporation of ambient fluid into the plume, a process called entrapment. Initial dilution results from the entrainment of ambient fluid into the plume as the plume rises to its trapping level. The magnitude of initial dilution depends on a number of factors including, but not limited to, the depth of water, ambient density stratification, discharge rate, buoyancy, port spacing (i.e. plume merging), and current velocity. These factors may be referred to collectively as the diffuser flow configuration or simply the flow configuration. Depending on the flow configuration, the initial dilution may be less than 10 or greater than 500. As attaining water quality criteria may often require relatively high initial dilution, the need to be able to estimate initial dilution for various flow configurations becomes apparent. Other than actually sampling the water after a facility is in operation, there are various ways to estimate pollutant concentrations achieved in the vicinity of a particular diffuser. A scale model faithful to all similarity criteria could yield the necessary dilution information. Dimensional analysis and empirical formulae may also be very useful. Alternatively, a numerical model based on the laws of physics may be developed. This method is chosen to provide initial dilution estimates here because it is more cost-effective than field sampling and more accurate than a scale model. Any numerical model used to provide dilution estimates should faithfully replicate the relevant plume relationships and should be verified for accuracy. The plume model MERGE (Frick, 1981c) accounts for the effects of current ambient density stratification and port spacing on plume behavior. In addition, it has been extensively verified (Frick, 1981a, 1981b; Tesche et al., 1980; 317 ------- Policastro et aj_._, 1980; Carhart et al_._, 1981). There are several ways of presenting the initial dilution estimates. MERGE may be run for specific cases or run for many cases spanning a range of conditions and presented in nomogram or tabular form. The latter method is the most compact. The resulting initial dilution tables display values of dilution achieved at the indicated depths and densimetric Froude numbers. One hundred tables are presented in Appendix 6 for various combinations of port spacing, density stratification, and effluent-to-current velocity ratio. Before describing the tables in more detail and discussing examples, it may be helpful for some users to read the following, occasionally technical, discussions of the plume model MERGE (Section 6.5.2.2) and of basic principles of similarity (Section 6.5.2.3). Others may want to advance directly to Section 6.5.2.4 describing table usage. 6.5.2.2 The Plume Model JCRGJE MERGE is the latest in a series of models whose development began in 1973. Various stages of model development have been recorded (Winiarski and Frick, 1976 and 1978; Frick, 1981c). In the realm of plume modeling, MERGE belongs to the Lagrangian minority since more models are Eulerian. The model can be demonstrated to be basically equivalent to its Eulerian counterparts (Frick and Winiarski, 1975; Frick, 1981c). Time is the independent variable which is incremented in every program iteration based on the rate of entrainment. To simplify the problem, many assumptions and approximations are made in plume modeling. In MERGE, steady-state is assumed and the plume is assumed to have a round cross section everywhere. The MERGE user may input arbitrary current and ambient density profiles. The model includes a compressible equation of continuity so that the predictions are also valid for highly buoyant plumes. It accounts for merging of adjacent plumes but only when the ambient current dilution is normal to the diffuser pipe. In many cases, this is not a significant restriction as many diffusers are oriented to be normal to the prevailing current direction. 318 ------- The model contains an option for using either constant or variable coefficients of bulk expansion in the equation of state. The water densities in Table VI-19 are generated using the model's density subroutine based on actual temperatures and salinities (i.e. effectively using variable coefficients). If temperature and salinity data are unavailable then the model can be run based on density data alone. The latter method is satisfactory for relatively high temperatures and salinities because the equation of state is relatively linear with these variables in that range. However, for low densities and temperatures gross inaccuracies may result. Unfortunately, the initial dilution tables are based on the latter method. A more accurate representation would greatly increase the number of tables necessary to cover all the cases. Users with applications involving cold, low salinity water are urged to run the more accurate form of the model. The success of MERGE in predicting plume behavior is primarily attributable to two unique model features. The first of these relates to the expression of forced entrainment. Entrainment may be attributed to the velocity shear present even in the absence of currents, i.e. aspiration, and to current-induced entrainment, sometimes called forced entrainment. The forced entrainment algorithm in MERGE is based on the assumption that all fluid flowing through the upstream projected area of the plume is entrained. This hypothesis is based on well-established principles and observations (Rawn et a!., 1960; Jirka and Harlman 1973). Paradoxically, the hypothesis has never been implemented in numerical models before. The projected area normally contains linear and quadratic terms in plume diameter, whereas in conventional modeling, forced entrainment is generally expressed as a linear function of diameter. It is necessary to include additional sources of entrainment to make up the difference when so expressed. The second feature is the use of a constant aspiration coefficient. This coefficient is often considered to be variable (e.g. Fan, 1967). The need for a variable coefficient is attributable to the fact that many models predict centerline plume values. For plumes discharged vertically upward into density stratified ambient water, such models are expected to predict the maximum penetration of the plume. To achieve agreement requires a relatively small aspiration coefficient. However, when the same models are used to predict the 319 ------- Table VI-19a WATER DENSITIES (EXPRESSED AS SIGMA-T)* CALCULATED USING THE DENSITY SUBROUTINE FOUND IN MERGE TEMPERATURE(°C) 24 5 8 10 12 14 u 5 10 15 -0.993 .721 1.535 2.31.8 3.159 3.978 9.590 6.399 7.207 8. 015 8.822 9.628 12.01.5 -0.031. .776 1.586 2.395 3.203 d.Olfl 5.623 6.1.28 7.233 8.037 8.81.0 9.61.3 10.1.1.6 11. 2*8 12.01.9 .007 .Sid 1.628 2.1.25 3.230 d.G33 d. 836 5.639 6.1.1.1 7.21.2 8.0d2 8.8ii2 9.61.2 lO.ddl 11.21.0 12.038 .331 .835 1.637 2.d39 3.21.0 - d.OVO d.81.0 5.639 6.dI7 7.235 8.032 8.829 9.625 10.1.21 11.217 12.012 .039 .839 1.638 2.1.37 3.23d d.031 d.828 5.623 6.1.18 7.213 8. 007 8.821 9.59d 10.387 11.179 11.971 .030 .827 1.623 3.213 d.007 d.SOQ 5.593 6.385 7.176 7.967 . 8.758 9.5d8 10.338 11.127 11.916 . BC6 .BOO 1.593 2.385 3.177 3. 968 d.758 5.5d8 6.337 7.125 7.913 8. 7 Gl 9. d88 10.275 11. 062 11. 8d8 -0.032 .758 1 .5d8 2.338 3.126 3.911. d.701 5.d88 6.271. 7.060 7.8«.5 8.630 9.dl5 10.199 10.983 11 .766 -C.086 .702 1.1,89 2.276 3.061 3.81.7 d.631 S.dl5 6.199 6.982 7.761. 8.51.6 9.328 10.109 10.890 11.671 -0.15d .632 1.1.16 2.200 2.983 3. 765 d.5d7 5.329 5.109 6. 890 7.670 8.1,1.9 9.228 10.007 10.786 11 .56<« -8.235 ,5dS 1.329 2.111 2.891 - 3.671 1..I.50 5.229 6.007 6.785 7.563 8.31.0 9.116 9.893 10.669 11.1.1.5 -0.330 . d50 1.230 2. ooa 2.786 - 3.56d d. 3dl 5.117 5.893 6. 66S 7. dd3 8.218 8.992 9.766 10.5dO 11.313 -0.d3B 1.117 1.893 2.669 — S.ddd d.218 d.992 5.766 6.539 7.S12 - 8.081. 8.856 9.628 10.399 11.170 -0.558 .217 .992 1.766 2.539 3.312 d.856 5.627 6.398 7.168 7.939 8.708 9.d78 10.21.7 11.016 -0.691 .•82 . 85d 1.626 2.397 -s.iea 3.938 d.7CS 6.2d5 7.91* - 7.782 6.?d9 9.317 l«.3Sd 10. 851 f\j 0 12.850 12.851 12.836 12.807 12.763 12.705 12.63d 12.51.9 12.d52 12.3d2 12.220 12.087 11.91.1 11.785 11.618 O 5 13.65d 13.652 13.63d 13.6D2 13.555 13.d9d 13.d20 13.332 13.232 13.120 12.996 12.860 12.712 12.55d I2.38d <3^- Id.d59 id.d53 Id.1.32 Id.196 Id.3d6 l'd.2B2 Id.205 Id.115 Id.013 13.898 13.771 13.633 13.1.83 13.322 13.151 -— on IS.263 I5.25d 15.229 15.190 15.137 15.071 Id. 991 Id.898 Id.793 Id.676 Id.5d7 Id.d06 ld.25d Id.091 13.917 20 16.067 16.05d 16.027 15.985 15.929 15.85° 15.777 15.681 15.573 15.d53 15.322 15.179 15.025 Id.860 ld.68d £H 16.870 16.855 io.82d 16.779 16.720 16.6d7 16.562 16.d6d 16.35d 16.231 16.097 15.952 15,796 15.628 15.d51 i—i 17.67d 17.655 17.621 17.573 17.511 17.1.36 17.3d7 17.2d7 17.13d 17.009 16.873 16.725 16.566 16.397 16.217 Z 18.d78 18.1,55 I8.dl8 18.367 18.302 18.22d 18.133 18.030 17.91d 17.787 .17.6d8 17.d98 17.337 17.166 16.98d >~\ 19.281 19.255 19.215 19.161 19.093 19.012 18.919 18.813 19.69', 18.565 18.d2d 18.271 16.108 17.935 17.751 ------- Table VI-l9b WATER DENSITIES (EXPRESSED AS SIGMA-T)" CALCULATED USING THE DENSITY SUBROUTINE FOUND IN MERGE TEMPERATURE (°C) 16 18 20 22 24 26 28 0 5 10 ^ 15 o c^ r 2° -0.836 -0.065 .7C5 2.21,1. 3.012 3.780 5.315 6. 082 6.81.8 8.379 9.11.5 9.910 10.675 11. «.39 12.201. 12.969 iiiiii. -0.993 -0.221. .51.1. 1.312 2.079 2.e<.5 3.611 «,. 377 5. 11.2 5.9Q7 6.671 7.*i35 8.198 3.962 9.725 13. 1.48 11.251 12.013 12.776 1 3.539 11,. 331 -1. 161 -0.391. .372 1. 133 1.9C3 2.667 3.1.31 <». 195 <>.958 5. 721 6,1.33 7.21.5 8. 007 8. 768 9.530 10.291 11.052 11.813 12.573 13.331, -1. Ji.1 -0.576 .189 .952 1.715 2.1.78 3.21.0 i.. 002 I..763 5.521, 6.285 7.QI.5 7.805 8.565 9.321. 10. 083 10. 81.3 11.602 12. 361 13. 120 13. 879 -1.532 -0.763 -0.836 .756 1.518 2.279 3.039 3.799 <..S58 5.317 6.076 6.335 7.5=3 8.351 9.108 9.866 10.623 11. 381 12. 138 12.395 13.653 -1.733 -3. 971 -0.211 .550 1.309 2. 063 2.8Z7 3.585 I..31.3 5.100 5.857 6.611, 7.371 8.127 8.883 9.639 10.395 11.150 11.906 12.652 I3.m7 -1.91,5 -1.185 -0.1.26 .333 1.091 1.81.8 2.605 3.362 «.. 118 <>. 873 5.629 6.381, 7.139 7.893 8.61,8 9.1, 32 10. 156 10.910 11. 661, 1 Z . •» 1 8 13. 173 -2.167 -1.1.09 -0.651 .106 .862 1.613 2.373 3.128 3.882 I.. 636 5.390 6.11,1, 6.397 7.650 8 .1.03 9.15t 9.908 10 .661 12.166 12.919 -2.399 -1.6I.Z -0. 887 -0.131 .623 1.377 2.131 2.381. 3.637 •,.390 5.11,2 5.891. 6.61.6 7.397 8.1<>9 8.900 9.651 10.1.02 11.153 11.901. 12.655 -2.61.1 -1.386 -1.132 -0.378 .375 1.127 1.830 2.631 3.383 1..8S5 5.635 6.385 7.135 7.885 3.635 9.385 10.131. 10. 381. 11.631. 12.381, -2.893 -2.139 -1.387 -0.635 .117 .868 1.619 2.369 3.119 3.868 ',.618 5.367 6.116 6.861, 7.613 8.361 9.109 9.453 10.606 11.351. 12.133 -3. 151. -2.1.02 -1.651 -C.901 -0.150 .599 1.31.8 2.397 2.81.6 3.591. <.. 31.2 5.089 5.837 6.581. 7. 331 8.078 8.825 9.572 10.319 11.066 11. 913 -3.1.25 -2.671, -1.925 -1 .176 -fl.i.27 .321 1.069 1.816 Z.563 3,310 I.. OS 7 <«.S03 5.51.9 6.295 7.01,1 7.786 8.512 9.278 10.023 10.769 11.515 -3. 731, -2.956 -2.208 -1.1.60 -0. 713 .031. .780 1.526 2.272 3.017 3.763 W.507 5.252 5.997 6. 71,1 7.1,36 3.230 8.975 9.719 10.1,61. 11.203 -3.993 -3.2«,6 -1.753 -1.007 -0.262 .%83 1.228 1.972 2.716 3.S60 5.690 6.1,33 7.176 7.920 8.663 9.* 86 10.893 16.027 15.827 15.617 15,397 15=168 H..929 n,.6m 11..I.3I. 1U.158 13.881, 13.600 13.308 13.007 12.698 12.381 16.792 16.590 IS.378 IS.155 15.925 15.685 15.W36 15.177 11..910 H. bji» l«,.3i.9 K..056 13.75U 13.1.1.3 13.125 o c J---557 17.353 17.139 16.91& 16.683 16.t.iil 1&.19Q 15.931 15.662 15.381. IS.098 lt.,803 H. 500 !»*. 189 13.869 18.322 18.115 17.901 17.576 17.1.1.1 17.19a 16. 91.516.681. 16.1.11. 16.135 1S.8I.8 15.552 15.21.7 1<>.935 llt.6t» 19.087 18.880 18.662 18.1,36 18.200 17.955 17,701 17.1.38 17.166 16.886 16.597 ~16.30 0 15.995 15.681 15.359 19.853 19.61,3 19.1.2<. 19.196 18.958 16.712 18.H56 18.192 17.919 17.637 17. 3<,7 17.0<,9 16.71.Z 16. <,28 16.185 20.619 20.1,08 20.187 19.957 19.717 19.1.69 19.Z12 1S.9<,& 18.672 18.339 13.098 17.798 17.«.90 17.175 16.851 Qn 21.385 21.172 20.91.9 20.718 20.1.77 20.227 19.96S 19.701 19.1.25 19.11.1 1S.B1.9 18.51.8 18.239 17.9Z2 17.597 ^U 2_2_._152 21.937 21.713 21.U79 21.236 20.985 20.725 20.1.56 20.179 19.891. 19.600 19.298 18.988 18.670 18.3«»* 22.919 22.702 22.1.76 22.21,1 21.997 21.71.1. 21.I.8Z 21.212 20.931. 20.61.7 20.352 20.01,9 19.738 19.1,19 19.091 23.687 23.1,68 23.2<,0 23.003 22.757 22.503 22.?«,0 21.968 21.689 21.WJ1 21.10«> 20.800 20.".88 20.168 19.8«tO 2I..1.55 Z1..235 2I..OC5 Z3.766 23.519 23.263 22.998 22.725 22. <»«* 22.155 21.857 21.552 21.239 20.917 20.588 on 1^-221. 25.001 ?<.. 770 2U.530 2»,.2ei 2I..023 23.75r 23.1.83 23.200 22.910 22.611 22.3QI. 21.990 21.668 21.338 fes-993 25.769 25.536 25.291. 25.QI.3 21..78I. 21..51& 2i,.2i>l 23~.957 23.665 23.365 23.058 22.71,2 22.S19 2270^8 26.763 26.537 26.302 26.058 25.806 25.51.5 25.277 21..999 24.711. 2V.1.21 2^.120 23.811 23.1.95 23.171 22.839 27.53U 27.306 27.069 26.821. 26.570 26.308 26.037 25.759 25.1,72 25.178 21..876 21..566 2 28.866 28.599 ?TT32i. 28.31.2 27.751 27.1.53 27. mB 26.835 26.511, 26.186 25785T •*• ~ ~~ ' Sigma-t (at) is defined as: (density-1) x 103. For example, for seawater with a density of 1.02500 g/cm3, at = 25. ------- Table VI-19c WATER DENSITIES (EXPRESSED AS SIGMA-T)* CALCULATED USING THE DENSITY SUBROUTINE FOUND IN MERGE TEMPERATURE (°C) 5 I 10 .177 -0.138 -fl.ii61--0.7g3 -1.131. -l._ 10.569 10.237 9.897 9.5U9 9.192 8.827 8. yi5 8.07^ 7.685 7.288 6.881. 6.1.71 6.050 5.622 5.188 [_ 11.312 10.979 10.638 10.288 9.931 9.56S 9,191 8.809 8. ".20 8.022 7.617 7.203 6.782 6.353 5.915 I—" 12.055 11.721 11.378 11.028 10.669 13.303 9.92s 9.5C.& 9.155 8.757 8.350 7.936 7.51«i 7.081. 6.6«.6 ^ 12.798 12.".63 12.119 11.768 H.i.08 11.0«.l 10.666 10.282 9.891 9. ".91 9.06U 8.669 8.2".6 7.816 7.377 —I or 13.5M 13.205 12.861 12.508 12.m8 ll.?80 11.1.03 ILQIS 10.627 10.227 9.819 9.J.33 8.980 8.51.8 8.109 eC C. 5 1<«.285 13.9<.8 13.602 13.21.9 12.888 12.519 12.11.2 11.757 11.361. 1J.953 10.551. 1C.138 9.71«t 9.282 B.8'>2 00 15.029 1<».691 li,.3<.5 13.990 13.628 13.258 12.881 12.<»9S 12.101 11.700 11.291 10.871. 10.".1.9 10.016 9.576 15.773 15.1.3". 15.087 I",.732 1<..3&9 13.999 13.620 13.233 12.839 12.1.37 12.027 11.610 11.181. 10.751 10.310 16.518 16.178 15.830 15.".75 15.111 li.,739 1I..3&Q 13.973 13.578 13.175 12.765 12.3<»7 11.921 ll."»87 11.0 1&.9Z3 16.57^ 16.217 15.853 iS.i.81 15.101 j!.. 713 Id.317 13.911* 13.503 13.08fe 12.658 12.22". 11. 762 30 18.010 17.668 17.318 16.981 16.596 16.223 15.BJ.2 15.'i.5it 15.057 l<..65t» 1<».2^2 13.823 13.396 12.962 12.520 18.757 18.1.11. 18.063 17.7&5 17.339 16.965 le.Seu 16.195 15.798 15.39". 1J..9S2 ln.563 lis.136 13.701 13.258 19.50". 19.160 18.809 18.1.50 18. 0 «3 17.709 17.32? 16.937 16.51.0 16.135 15.723 15.303 11..S76 !•.. <.<.! 13.9«8 20.252 19.907 19.555 19.195 18.826 18.1.53 1S.S70 17.680 17.283 16.878 16.1.&5 16.0^.5 15.617 15,182 1"..739 0 c 21.300 23.655 20.332 19.91.1 19.573 19.19"i 18.t»15 I'.'.Z'. 18.026 17.621 17.208 16.767 16.359 16.921; 15.1.81 JD M-71.9 21.1.03 21.05D 20.688 20.320 19.9".% 19.S6Q 19.169 <8.771 18.366 IT.952 17.531 17.103 16.667 16,22'. 22.1,99 22.153 21.798 2l.«.3& 21.067 20.69Q 20.3C6 19.915 '9.516 19.110T8.696 18.276 17.8".7 17.1,12 16.969 23.250 22.903 22.S<.7 22.185 21.315 21.1.38 21.05s. 20.662 20.263 19.856 ig.'.'.Z 19.H21 18.593 18.157 17.71V 2«toOQ2 23.653 23.298 22.935 22.561. 22.187 21.802 21.1.09 21.010 20.603 20.190 19.766 19.31.0 1S.90<> 18.W61 /in ?«>-754 2U.1.C5 21..0-.9 23.615 23.3H. 22.97 6_2r «j«i 1 22.158 21.759 21.352 20.938 7B.S17 20.088 19.653 19.210 ^U ?_5.5C8 2S.358 Z».80i Ji..^T7 ju.oss Z3.6"97 23.$01 2^..aa& 21.Sit, 2.Z.101 L\. 6i7 il. Z&» 25-836 ? ^ 0 ? J 3 .,9 6 C * Sigma-t (at) is defined as: (density-1) x 103. For example, for seawater with a density of 1.02500 g/cm3, at = 25. ------- trajectories of horizontally discharged buoyant plumes, a larger coefficient is required. Consequently the aspiration coefficient must be variable. Although relatively advanced, MERGE does have its limitations. Some of these are a result of the assumptions already discussed. For example, the plumes are assumed to be round, whereas some evidence indicates substantial deviation from this idealization (Abramovich, 1963). Other important limitations are listed below. 1. Diffuser parallel current: The model does not predict plume dilution for cases of current flowing parallel to the diffuser pipe. This is a severe limitation especially in some ocean applications because this case may be expected to result in the lowest initial dilutions. 2. Surface entrainment interference: The model does not properly account for interfacial boundary conditions. Dilutions near the surface or bottom may be overestimated because entrainment will be assumed where water is unavailable for entrainment. 3. Horizontal homogeneity: The model assumes homogeneous horizontal current although bottom topography, internal waves, or other factors may cause considerable spatial flow variations. This is in addition to temporal variations which are excluded by virture of assumed steady-state. 4. Uniform discharge: It is assumed that an infinitely long diffuser exists for which there is no port-to-port variation in effluent characteristics. 323 ------- 6.5.2.3 The success of a set of tables in describing an infinite number of possible diffuser, effluent, and ambient flow configurations depends on the principles of similarity. Basically, similarity theory states that model and prototype will display equivalent behavior if a limited number of similarity conditions or parameters are preserved. Equivalent behavior means that relative to appropriate measures the behavior will be equal. For example, if all similarity parameters are preserved, then the height of rise predicted by the model and observed in the prototype will be equal when measured in terms of the initial diameters of the corresponding plumes. The number of similarity conditions is determined by the difference between the number of independent variables and primary variables involved in the problem (Streeter, 1961). Primary variables must include mass, time, and distance. The present problem involves eleven independent variables implying eight similarity conditions. The independent variables, corresponding symbols, units, similarity parameters, and their names are listed in Table VI-20. As the dilution tables are based on a linear equation of state, the effluent and ambient densities p and p, , respectively, replace four independent variables: the effluent and a ambient salinities and temperatures. This effectively reduces the number of similarity conditions by two to six. It is advantageous to further reduce the number of similarity conditions to minimize the number of tables necessary to represent the flow conf iguratons of interest. From experimental observations, it is found that plume behavior is basically invariant for large Reynolds numbers reducing the number of similarity conditions to five. Finally, the ratio Pe/Pa and the stratification parameter can be combined in a composite stratification parameter, SP, where, SP = (pa-pe)/(d0dpa/dz) This is a satisfactory similarity parameter providing that differences in model and prototype densities are not too great. The assumption is valid for discharge of municipal waste water into estuarine or coastal waters. Figures VI-28 and VI -29 demonstrate the effectiveness of this parameter. The same similarity conditions are shared for both cases. The two figures show rise 324 ------- Table VI-20 PLUME VARIABLES, UNITS, AND SIMILARITY CONDITIONS Variable Symbol Units Dimension!ess Sim. Farm Name OJ r\j en Effluent density Effluent velocity Effective diameter Ambient density Reduced gravity Density stratification Current velocity Kinematic viscosity Port spacing Pe v do Pa 9' dpa/dz v Si ML LT L ML LT" -3 -1 -3 ML" LT -i none—primary variable none—primary variable none—primary variable Pe/Pa Pe/(d0dpa/dz) ua/v d0/v none none none density ratio densimetric Froude number: Fr stratification parm. current to effluent velocity ratio: k Reynolds number: Re Port spacing parm.: PS Notes: 1. g1 = ((pa-pe)/pe)g where g is the acceleration of gravity (9.807 msec ")• 2. In the present application a composite stratification parameter, SP, is used in lieu of the density ratio and the stratification parameter. SP = (pa-pe)/(d0dpa/dz) 3. The diameter, d is taken to be the vena contracta diameter. ------- CASE NUHbER 1 • ••*» TEST OF COMPOSITE STRATIFICATION PARAMETER INPUT DATA PSEUDO-ECHO U 7.0200 0.0000 A 0.1160 T 0.0000 s 0.0000 B SPC 0.0500 100.0000 ALT PEN 0.0000 NDP ITFR IFRQ NAA NAB MAC IDENSM 2 1000 25 0 0 0 1 (IF IDENSrfrl THEN DENSITY VERSION USED—USE 2ND SIGMAT COL) AMBIENT STRATIFICATION (AND CALCULATED SIGMAT) OJ ro DEPTH(M) TEKP(C) SAL(OXOO) 0.000 0.000 0.000 . 10.000 0.000 0.000 EFFLUX TO CURRENT RATIO(K) . . DFN5IHETR1C FROIIOE "0. .... VOLUME FLUX (H»* 3/S) . ..... DEPTH AVE STRATIFICATION PARK. PORT PORT CUR(MSS) SIGMAT 0.000 -0.093 0.000 -0.093 99999.0 43.1 SIGHAT(DEN 0.000 27.000 VER) 0.055 3703. 10. 7 0 7.02 0.000 O.OSOO MODEL OUTPUT AFTER -J- J 1 25 SO 75 100 125 IbO 175 200 225 250 275 300 325 350 J75 400 425 450 HOR CUH(X) 0.001 0.040 O.OP7 O.I4J 0.210 0.200 0.395 0.497 0.632 0.792 0.982 1 .208 1.477 1.797 2.177 2.628 3.162 3.792 4.534 NOMINAL TRAPPING 469 475 500 519 5.164 5.408 6.457 7.4(17 DEPTH(Z) 10.000 10.000 10.000 10.000 10.000 10.000 9.999 9.999 9.998 9.996 9.993 9.989 9.9H1 9.967 9.944 9.907 9.845 9.747 9.601 LEVEL REACHED 9.454 9.403 9.196 ?.m D1AMETFR 0.100 0.110 0.140 0.167 ' 0.198 0.235 0.279 0.3J2 0.395 0.469 0.55P 0.6t.3 0.7b8 0.936 1.113 1.321 1 .56R 1.659 2.202 2.508 2.615 3.130 3.592 VOL OIL .007 .1«4 .403 .664 .973 2.342 2.7RO 3.301 J.97J 4.657 5.534 6.576 7.815 9.2S9 11.042 13.127 15.606 18.555 22.064 25.169 26.238 31.204 35.Fff(. HOR VEL(U) 6.972 5.903 4.964 4.174 3.510 2.952 2.482 2.087 1 .755 1.476 1.241 1 .044 0.878 0.730 0.620 0.522 0.439 0.369 0.310 0.272 0.261 0.219 0.192 ITERATIONS (MKS UNITS) VF.R VEL(V) 0.000 0.001 0,003 0.004 0,006 0.008 0.010 0.012 . 0.015 0.018 0.021 0.026 0.031 0.037 0.043 0.051 0.058 0.065 0.067 0.062 0.059 0.033 -O.Oof TOTAL VEL 6.972 5.903 4.964 4.174 3.510 2.952 2.482 2.08 ' 1.755 1.476 1.241 1 .044 0.876 0.73V 0.622 0.524 0.443 0.375 0.317 0.279 0,268 0.222 0.192 DEN 01FF 26.013 22.704 19.002 16.0S4 13.500 U.3S1 0.545 8.025 6.746 5. 66« 4.760 3.991 3.336 2.772 2.276 1.P22 1 .3«2 0.9?3 0.417 -O.OP1 -0.135 -0.627 -0.740 TIME 0.000 0.006 0.015 0.027 0.045 0.070 0.105 0.155 0.226 0.326 0.468 0.668 0.951 1.352 1 .917 2.715 3.839 5.416 7.b24 9.877 10.720 J5.U7 I9.7k9 CURRENT 0.000 0.000 0.000 0.000 0.000 0.000 0.000 o.ooo o.ooo 0.000 0.0«0 0.000 O.ono o.ooo o.ono O.oon O.OOfl o.ooo o.ooo o.ono o.ooo 0.0<>0 o.ooo FIGURE VI-28 EXAMPLE OUTPUT OF MERGE - CASE 1 ------- CASt NUMBER 2 *««*» TEST Of COMPOSITE STRATIFICATION PARAMETER INPUT DATA PSEUDO-ECHO II 2.J400 V 0.0000 0.1160 T 0.0000 0.0000 n SPC 0,0500 100.0000 ALT DEN 0,0000 NDP 1TCR IFRQ NAA NAB NAC IDENSW 2 1000 25 0 0 0 t (IF IDENSHit THEN DENSITY VERSION USED—USE 2ND SIGMAT COL) AMBIENT STRATIFICATION (AND CALCULATED SIGMAT) CO DEPTHt") TEMPIC) SAt(0/00) 0.000 0.000 0.000 10.000 0.000 0.000 EFFLUX TO CUHRFNT RA1IO(IO . . DEPTH AVE DEPTH(M) DISCHARGE STRATIFICATION PARM. PORT HADIUS(H) . PORT SPACINC(N) CURCM/5) 0.000 0.000 , 99999.0 • 43.1 SIGMAT -0.093 -0.093 SIGMATCDEN VER) 0.000 3.000 0.018 J3333.3 i 10.0 2.34 , 0.000 0.0500 100.00 NODtL OUTPUT AFTER -J- J HOR 1 25 50 75 100 175 150 175 200 225 250 275 300 325 350 375 400 425 450 COR(X) 0.001 0.041 0,0«9 0.146 0.214 0.295 0.392 0.506 0.643 0.905 0,996 1.227 1.500 1.624 2.209 2.666 3.206 3.643 4.592 NOMINAL TRAPPING 469 475 500 517 5.213 5.476 6.537 7.J90 DEPTH(Z) 10.000 10.000 10,000 10.000 10.000 10.000 9,999 9,999 9.999 9.996 9.993 9.98« 9.980 9.966 9.942 9.902 9.939 9.736 9.595 LEVEL REACHED 9.443 9.392 9.177 s. in DIAMETER 0.100 0.118 0.141 0,167 0.199 0.237 0.292 0.335 0.398 0.473 0.563 0.669 0.796 0.946 1.124 1.336 1.565 1.B79 2.22S 2.518 2.644 3.167 3.583 VOL OIL 1.007 1.169 1.413 1.680 1.997 2.374 2.873 3.356 3.991 4.746 5.643 6.710 7.979 9.49R 11.203 13.417 15.955 18.973 22.563 2S.561 26.R32 31.909 35-.960 HOR VEL(U) 2.324 1.968 1,655 1.391 1.170 0.964 0.927 0.696 0.585 0,492 0.414 0.34R 0.2^.' 0.246 0.207 0.174 0.146 0.123 0.103 0.091 0.087 0.07J n.Ob* ITERATIONS (HKS UNITS) VER VEL(V) 0,000 o.ono 0,001 0.001 0.002 0.003 0.003 0.004 0.005 0.006 0.007 0.009 0.011 0.013 0.015 0.017 0,020 0.022 0.023 0.021 0.020 0.010 O.OOff TOTAL VEL 2.324 1.96b 1,655 1 .391 1.170 0.984 0.827 0.696 0.585 0.492 0.414 0.34H 0.293 0.246 0.207 0.175 0.148 U.125 0.106 0.094 0.089 0.074 0.06!> DEN DIFF 2.979 2.573 2.121 1.7g4 1 .500 1 .761 1 .061 0.«92 0.749 0.630 0.529 0.443 0.370 0.10R 0.252 0.201 0.152 0.100 0.04) -0.002 -0.019 •0.073 -0,0*3 TIME 0.001 0.019 0.046 0,084 0.138 0.214 0.322 0.474 0.6S9 0.994 1.425 2.034 2.895 4.112 5.HJO 8.254 1 1 .666 16.450 23.140 29.563 32.525 45.931 58.379 CURRENT 0.000 0.000 0.000 0.000 0.000 0,000 0,000 0.000 o.ooo 0.000 0.000 0.000 0,000 n.ooo 0,000 0.000 n.ooo 0.000 0.000 0.000 0.000 o.o°o o.ooo FIGURE VI-29 EXAMPLE OUTPUT OF MERGE - CASE 2 ------- and dilution to be within about a percent of each other even though the stratification and initial buoyancies are much different. With only four similarity conditions to be satisfied, the problem can be represented by considerably fewer model runs than if six similarity conditions were required. 6.5.2.4 Table Usage To use the dilution tables to estimate dilutions, it is necessary to calculate the appropriate similarity parameters and know the depth of the outfall. Calculation of the four similarity parameters Fr, SP, k, and PS, given in Table VI-20 requires knowledge of all the variables except v. The dilution tables are shown in Appendix G. The depth used in the dilution tables is expressed in terms of the diameter of the ports; that is, the vena contracta diameter. For bell-mouthed ports, this diameter is approximately equal to the physical diameter of the port. Thus, if the actual depth of water is 10 m and the port diameter is 10 cm, then the depth of water is 100-port diameters. The dilution tables are numbered from 1 through 100 and are grouped by port spacing as listed below: Tables Port Spacing (PS) (Diameters) 1-20 2 21-40 5 41-60 10 61-80 25 81-100 1000 (effluent from each port acts as a single plume) Each group of 20 is further subdivided by current velocity to effluent velocity ratio (k), i.e., 328 ------- Current. Velocity to Effluent Tables Velocity Ratio (k) 1-5 0.1 6-10 0.05 11-15 0.02 16-20 0.00 (no current) Each subgroup of five tables is comprised of tables of varying composite density stratification (SP): Tables Composite Stratification Parameter (SP) 1 200 (high stratification) 2 500 3 2000 4 10000 5 infinity (no stratification) Finally, each table includes densimetric Froude number, Fr = 1, 3, 10, 30, 100, and 1000 to represent cases ranging from highly buoyant plumes to almost pure jets. The dilutions are tabulated with plume rise. The following examples demonstrate how the tables may be applied. EXAMPLE VI-11 Calculation of Initial Dilution ExampleA. This example demonstrates many of the basic features of the dilution tables and their usage. It also includes a method for estimating the plume diameter indirectly using information derived from the tables. The method is used in cases of unmerged or slightly merged plumes and is necessary to better estimate plume dilution when the plume is shown to interact with the water surface. 329 ------- Given that waste water is discharged horizontally at a depth of 66 m from a simple pipe opening and that: u = the current velocity = 0.15 m/s a v = the effluent velocity = 1.5 m/s Pe = the effluent density = 1000 kg/m3 p = the ambient density at discharge depth = 1015 kg/m3 a L = the port spacing = 3.4 m d - the port discharge vena contracta diameter = 1.7 m, and dpa/dz = the ambient density stratification = 0.0441 kg/m4. The four similarity parameters necessary to use the tables are: Fr = the densimetric Froude number = 3.0 k = the current to effluent velocity ratio = 0.1 SP = the composite stratification parameter = 200, and PS = the port spacing parameter = infinity. The infinite port spacing indicates that the dilutions will be found in the last 20 tables of the dilution tables in Appendix G, i.e. Tables 81-100. These tables are appropriate because merging does not occur with PS = infinite. The current to effluent velocity ratio of 0.1 indicates that the appropriate dilutions are among the first five of these 20 tables. The stratification parameter 200 identifies the first of these five tables as the correct reference location. Finally, the densimetric Froude number of 3.0 isolates the second column as the one containing the information of interest. 330 ------- The column of dilutions contains a wealth of information about the plume whose overall behavior is described in Figure VI-30. After rising one diameter (1.7 m), the average plume dilution (expressed in terms of volume dilution) is 2.8. In other words, a given amount of plume volume has been diluted with 1.8 times as much ambient fluid. After rising 2 diameters (3.4 m), the average dilution is 3.7, and so on. At 15 diameters rise, the dilution is 21.4. The next entry follows in a line headed by "T", indicating that the initial trapping level has been reached. This means that the plume and ambient densities are equal at this level and momentary equilibrium has been attained. The "trapping" level dilution is 26.2 and the corresponding plume rise, set off in parentheses to the right of the dilution, is 17.0 diameters. The parentheses are a mnemonic for indicating trapping while values set off in square brackets are merging level plume rises. When a plume intercepts the water surface, it is deprived of some of its entraining surface and consequently the dilution is less than that indicated in the tables. For well-diluted, unmerged or slightly merged plumes, with k not equal to zero, the plume diameter, d, may be estimated: d = d0/D/T (VI-61) In dimensionless units, or diameters: d/d - \/D/k (VI-62) In the present case, the diameter at maximum rise calculated in this way is 25.2 diameters (42.8m). Thus the top of the plume is 34.8 diameters (22.2 + 12.6) above the level of the outfall, i.e. 12.6 diameters above the plume centerline, and 5.2 diameters below the surface. Therefore, surface interaction does not occur. For the sake of comparison, the plume diameter calculated by the program at maximum rise is 23.5 diameters which compares favorably with the simplified estimate made above. 331 ------- co CO no ';• .».•; -.'; -.": • -.o>^d if f u ser '. '•". T.'°..•'.-- •«,.;.';f«>-»>^ FIGURE VI-30 SCHEMATIC OF PLUME BEHAVIOR PREDICTED BY MERGE IN THE PRESENT USAGE ------- , a Example B. Suppose that all the conditions given in Example A apply here except that the depth of water is only 29.7 diameters (50.5 m). Table 81 is again used to provide dilution estimates; however, surface interaction does occur. A conservative estimate of initial dilution is obtained by assuming that entrainment stops as soon as the top boundary of the plume intersects the surface. In reality, some additional ambient water could be expected to enter- through the sides of the plume. When the centerline depth of the plume is 20 diameters, its dilution is 37.3 and its approximate diameter is 19.4 diameters (33 m). Consequently, the top boundary of the plume is 29.7 diameters above the level of the outfall and is equal to the depth of water. Thus the dilution of 37.3 provides a conservative estimate of initial dilution in this case. Example C. Suppose the following data apply: - 0.15 m/s v =1.5 m/s pe = 1000 kg/in pa - 1015 kg/m S-j = 0.34 m dQ - 0.17 m, and dpa/dz - 0.0441 kg/m". Then, Fr = 9.5, k = 0.1, SP - 2000, and PS = 2, and Table 3 in Appendix G is the appropriate source of dilution information. As the Froude number is almost equal to 10, column 3 information can be used without modification although interpolation may be appropriate in some applications. The plumes merge almost immediately at a dilution of 2.1. The initial trapping level is encountered after the plume rises 89.4 diameters (15.2 m). The maximum dilution is 76.2 after rising 125 diameters (21.3 ). 333 ------- For closely spaced plumes, the diameter may be estimated from the relationship: d/do = (irD) (4 k PS) (VI-63) The maximum diameter estimated in this way is 299 diameters (50.9 m). In contrast, the program gives a value of 268 diameters (45.5 m). No surface intraction occurs in deep water. In very shallow water, a conservative estimate of dilution may be made by dividing the total flow across the length of the diffuser by the flow through the diffuser. It is conservative because no aspiration entrainment is included in the estimate. Table 3 contains a blank entry in the second column of the 90-diameter rise line. The previous entry in the column indicates trapping. This means that trapping and the 90-diameter rise level occurred in the same iteration. Therefore, the dilution of 41.3 is the appropriate value for this blank. Example D. The methods given in Examples A and C for estimating the plume diameter are not accurate when intermediate degrees of merging exist. If surface interaction is important, it may be necessary to run the model to obtain accurate plume diameter predictions. Example E. Sometimes outfalls or diffusers are located in water only a few port diameters deep and, as a result, initial dilutions may be expected to be quite small. However, after the plumes reach the surface, they still have substantial horizontal velocity and continue to entrain ambient water more vigorously than a plume whose trajectory is unhindered by surface constraints. The workbook by Shirazi and Davis (1976) may be consulted to estimate additional dilution. Example F. Strong stratification inhibits plume rise. As stratification weakens, plume rise and dilution tend to increase. Predicting large dilutions and plume rises can require more program iterations than used to develop the tables in Appendix G. On the other hand, very large dilutions are usually of lesser interest. Consequently, the number of iterations is arbitrarily limited to 1000 and rise to 300 diameters. Table 94 provides examples in which the runs 334 ------- for each densimetric Froude number are limited by the permitted number of iterations. The final dilutions listed are underlined to remind the user that larger dilutions and plume rises occur. When the rise limitation criterion has been reached, a rise of 300 diameters or slightly more will be indicated. Example G. Many diffusers have horizontally discharging paired ports on each side of the diffuser. In cross current, the resulting plume behavior appears somewhat like that shown in Figure VI-31. The upstream plume is bent over by the counter flowing current and ultimately may be entrained by the downstream plume. The entrainment of pollutant laden fluid will reduce the overall dilution in the merged plumes. Estimates of the magnitude of this effect may be made if it may be assumed that: 1. the interaction occurs 2. there is merging of adjacent plumes to assure cross diffuser merging and not interweaving of plumes 3. the opposite plumes have similar rise and overall entrainment 4. there are no surface constraints, and 5. the actual (not permitted) rise is provided in the tables. The final dilution of the merged plumes, Df, is approximately: Df = (D2) (2D - De) (VI-64) where D is the dilution at maximum rise of the downstream plume as given in the tables and De is the dilution of the downstream plume upon entry into the bottom of the bent over upstream plume (see Figure VI-31). De is estimated by finding the distance in diameters, 1Q, between the depth at entry and the port depth. The dilution at this depth is read from the appropriate line in the dilution tables or interpolated. The maximum radius of the plume is added to the depth at which maximum rise occurs. The difference between the port depth and the depth so calculated is Ze. 335 ------- current merged dilution Df CO CO 'a •.' >'• -,•*' '«• ',' °.". •.'" ••» '.'<•••'••«': .-..•'" .. .-! '»—"i o.'o' . • . ' '. „• ,. .. • . "..••.. ? ..-..'• •''._•»•".•.•_"' •'-:.".•:'• ...' i .*'•.'•'•'.'.• .a. * •.' . '• .".'.'•.. ° •.._•:• o' *• a ;..*•*.'..*'•.*•'. ^ FIGURE VI-31 CROSS DIFFUSE-R MERGING ------- Given that Fr = 3, PS = 25, SP = 2000, and k = 0.1, and that identical plumes are injected into the ambient water from both sides of the diffuser. From Table 63, it is found that the dilution is 270 and the rise is 55.1 diameters. The width of the plumes may be estimated: d/d0 = (7r270)/[4(0.1)(25)] = 85 (cf. the computer calculated width of 83 diameters). Therefore, the vertical distance between the ports and the plume entry level is 55.1-85/2 = 12.6 diameters, and, De = 15.5 as estimated from the table at rise equal to 12 diameters. D^ may now be calculated: Df = 270/[2(270) - 15.5] = 139 This result may have been anticipated: the dilution is effectively halved. This is the outcome whenever the entry level, Z , is small. In many cases, halving the dilution provided in the tables gives an adequate estimate of the overall dilution achieved by the cross diffuser merging plumes. Example H. Given that PS = 25, SP = 200, k = 0.0, Fr = 10, and that an estimate of the centerline dilution at maximum rise is required. By consulting Table 77, it is found that the average dilution at maximum rise is 26.0. Since there is no current and virtually no merging, this value can be divided by 1.77 to obtain the centerline dilution (based on a gaussian profile, see Teeter and Baumgartner, 1979). The centerline dilution is 14.7. With identical conditions except for port spacing of 2 instead of 25, Table 16 shows that the dilution at maximum rise is 11.6. The centerline dilution is again smaller but not by the same percentage amount. For the 3/2 power profile, similar to the gaussian, the peak-to-mean ratio in stagnant ambient and complete merging is 1.43 (Teeter and Baumgartner, 1979). Thus the centerline dilution may be found to be 8.1. The peak-tc-rr;ean ratios given above are flow-weighted and are obtained through a stre-icht.for.vard integration. Unfortunately the problem is not as si.r.ple v;hen current is present because the caussian or other arbitrary profiles of velocity are superimposed onto a non-zero average velocity. Hence, in high 337 ------- current, the peak-to-mean ratio for single plumes assuming the 3/2 power profile is 3.89. For merged plumes, the ratio is lower. For intermediate currents, the ratio is between the corresponding extremes depending on the degree of merging and the actual current velocity. Fortunately, many standards and regulations - for example, the Federal 301(h) regulations - are written in terms of average dilutions. Also, repeated measurements in the field are likely to provide estimates of average concentrations before estimates of maximum concentrations are possible. Thus, the user of MERGE is normally not concerned with centerline dilutions. It is useful to remember that estimating average dilutions using centerline models involves not only the use of variable peak-to-mean ratios but also variable aspiration coefficients. END OF EXAMPLE VI-11 338 ------- 6.5.3 Pollutant Concentration Following Initial Dilution The concentration of a conservative pollutant at the completion of initial dilution is expressible as: Ce"Ca Cf = Ca + (vi-65) where C = background concentration, mg/1 a C = effluent concentration, mg/1 Sa = initial dilution (flux-averaged) Cf = concentration at the completion of initial dilution, mg/1. When the background level, CQ, is negligible Equation VI-65 simplifies to (VI-66) This expression can be used to predict the increased pollutant concentration above ambient, as long as the effluent concentration greatly exceeds the ambient concentration. It is interesting to note that when the effluent concentration is below ambient, the final pollutant concentration is also below ambient. Since water quality criteria are often prescribed as maximum values not to be exceeded following initial dilution, it is useful to rearrange Equation VI-65 to express the maximum allowable effluent concentration as follows: 339 ------- (cj = c e max a -Ca> (VI-67) where (C ) = maximum allowable effluent concentration such that water c f I IQA quality criteria are not exceeded. = applicable water quality criterion (Sa)min = minimum expected initial dilution Since initial dilution is a function of discharge and receiving water characteristics, as discussed in detail in Section 6.5.2, finding an appropriate "minimum" initial dilution is not a trivial problem. Most often, initial dilutions are lowest when density stratification is greatest. For a given stratification profile, dilutions generally decrease at lower ambient current speeds and higher effluent flow rates. Based on expected critical conditions in the vicinity of the discharge, the tables in Appendix G can be used to predict EXAMPLE VI-12 Analysis of the effluent wastewater from a treatment plant discharging into a large west coast estuary revealed that the effluent contained a number of priority pollutants. A few of the pollutants and their measured concentrations are shown below. Priority Pollutant Concentrations (yg/1) Criterion Level Dry Weather Wet Heather (yg/1) copper zinc mercury lindane 32.3 33.0 not detected 8.6 61.9 180.0 3.5 not detected 4.0 58.0 0.025 0.16 340 ------- The critical initial dilution has been determined to be 30. If the criterion levels are designed to be complied with at the completion of initial dilution, determine if the criteria for the four priority pollutants are contravened. A cursory review of the tabulations above shows that all detected effluent pollutant concentrations (i.e. undiluted concentrations) exceed the criteria levels, other than zinc during dry weather flow conditions. Hence if initial dilutions were to become low enough, each of the four priority pollutants could violate water quality criterion for either dry or wet weather conditions. Using the minimum initial dilution of 30, the final pollutant levels can be predicted using Equation VI-66, by assuming background levels are neglible. The final pollutant levels compared with the criterion levels are shown below. Final Concentrations (yg/1) Criterion Level Priori ty Po 11 utant Dry Weather Wet Weather (yg/1) copper zinc mercury lindane 1.1 1.1 - 0.3 2.1 6.0 0.1 - 4.0 58.0 0.025 0.16 Both mercury and lindane violate the criteria while copper and zinc do not, However, copper levels are sufficiently close to the criterion of 4.0 yg/1 to warrant further attention. END OF EXAMPLE VI-12 341 ------- 6-5.4 pH Followlng Initia! Pi 1ution The pH standard governing wastewater discharges into estuarine or coastal waters is usually quite strict. Typically, state standards require that the pH following initial dilution not deviate by more than 0.2 units from background. A step by step approach is presented here that can be used to determine whether a discharge will comply with a standard of this type. Step 1. The following input data are required: Sa = initial dilution Alk = alkalinity of receiving water, eq/1 Alk = alkalinity of effluent wastewater, eq/1 pHg = pH of receiving water pHe = pH of effluent wastewater Ka j, cKa j = equilibrium constant for dissociation of carbonic acid in wastewater and receiving water, respectively (first acidity constants) K-, o >cKa „ = equilibrium constant for dissociation of Q , 2. Q , / bicarbonate in wastewater and receiving water, respectively (second acidity constants) KW CK = ion product for wastewater and receiving water, respectively. Table VI-21 shows values of the equilibrium constants and ion product of water. For seawater, typical values of pH and alkalinity are 8.3 units and 2.3 meq/1, respectively. 342 ------- TABLE VI-21 VALUES OF EQUILIBRIUM CONSTANTS AND ION PRODUCT OF WATER AS A FUNCTION OF TEMPERATURE FOR FRESHWATER AND SALT WATER Temperature, °C 5 10 15 20 25 Temperature, °C 5 15 20 25 -log \f Freshwater 6.52 6.46 6.42 6.38 6.35 -log Xw Freshwater 14.63 14.35 14.17 14.00 f Seawater 6.00 5.97 5.94 5.91 5.84 Seawater 14.03 13.60 13.40 13.20 -log Freshwater 10.56 10.49 10.43 10.38 10.33 Ka,2 Seawater 9.23 9.17 9.12 9.06 8.99 343 ------- Step 2. Calculate the total inorganic carbon concentrations in the effluent wastewater (Ct ) and receiving water (C ): K Alk - -^r— + [H+] + Ln J and where e H+ e A1K, - _Kw + [H+] a a (VI-68) C = 5 (VI-69) a / . « . 1 [H+]2 + [H+] K. + K K (VI-70) d> 1 a> i 3,2 [H+]2 + [H+] K + K Ks a, i a, i a,2 Note: CK and CK are used in a, and a, to calculate a,i a,2 344 ------- Step 3. Calculate the akalinity (Alk ) and total inorganic carbon (C,f) at the completion of initial dilution: Alk - Alka (VI-72 Alk, = Alk + — ( L ' a Sa (VI-73) Step 4. Express the final alkalinity as: CK Alkf = Ctr (a, + 2a2)f + - [H+]f (vi-74) -f Rather than solving for [H ~\^ directly in Equation VI-74, it is easier to calculate Alk, in Equation VI-72 for a range of [H ] values, until the alkalinities computed from Equations VI-72 and VI-74 match. In most cases pH, will not differ from the ambient pH by more than 0.1 to 0.3 units. Consequently it is usually most expeditious to begin by assuming pH = pH . If pH >pH , then each subsequent calculation should be at 0.1 pH T a e a units higher than pH . If pH ------- TABLE VI-22 ESTIMATFD pH VALUES AFTER INITIAL DILUTION Seawater Seawater pH 5'C 10 In it 25 al Oi 50 ution 75 100 15 'C Initial Dilution 10 25 50 75 Effluent pH = 6.0 Alk 7 0 7 5 7.7 8.0 8.3 8.5 7.0 7.5 7.7 8.0 8.3 8.5 7.0 7.5 7.7 8 0 8.3 8.5 7.0 7.5 7.7 8.0 8.3 8.5 7.0 7.5 7.7 8.0 8 3 8.5 7.0 7.5 7.7 8.0 8.3 8 5 7.0 7.5 7.7 8.0 8.3 8.5 7.0 7.5 7.7 8.0 8.3 8.5 7.0 7.5 7.7 8.0 8.3 6.94 7.37 7.56 7.88 8 ?1 8^43 6.74 6.')8 7.07 7.27 7.56 B.01 6.63 6.80 6 86 6.98 7.21 7.51 6.45 6.55 6 58 6.64 6.73 6.83 6.92 7.32 7.49 7.80 8.15 8.38 6.85 7.18 7.31 7.60 8 00 8.26 6.75 6.99 7.07 7.25 7.61 7.95 7.03 7.52 7.71 8.00 8.30 8.50 7 07 7.54 7.71 8.00 8.30 8.50 6.97 7.44 7.64 7.95 8.26 8.47 6.87 7.23 7.39 7.70 8.08 8.33 6.81 7.10 7.2J 7.48 7.91 8 20 6.68 6.88 6.96 7.11 7.41 7.78 6.96 7.42 7.61 7.92 8.24 8.45 6.93 7.35 7 53 7.84 8. 19 8.41 6.88 7 23 7.38 7.67 8.06 8.30 7.01 7 51 7.70 8.00 8.30 8.50 7.0) 7.51 7.70 8 00 8.30 8.50 6 98 7.47 7 67 7.97 3.28 8.48 • 6.93 7 35 7 53 7.35 8.20 8.42 6.89 7.27 7.43 7.75 3.12 8.35 6.81 7 11 7.23 7.49 7.91 8.20 6.98 7 45 7.65 7.96 8 26 3.47 6.96 7.42 7.61 7.92 8.24 8.45 6.93 7 K 7 53 7.84 8.18 8.40 7 00 7.50 7.70 8.00 8.30 8.50 7.01 7 50 7.70 8 00 3.30 8.50 6 98 7.47 7 67 7.97 8.28 8.48 6.95 7.40 7.59 7.90 8.23 8.44 6.92 7.34 7.52 7.83 3.18 3 10 6.86 7.21 7.36 7.66 3.06 8.31 6.98 7.47 7.66 7.97 8.27 8.48 6.97 7.44 7.64 7.95 8.26 8.47 6.95 7.39 7.58 7.89 8.22 3.43 7 00 7.50 7.70 8 00 8.30 8.50 7.01 7.50 7.70 8.00 3.30 8.50 6 99 7.48 7.68 7.98 3.29 8.49 6.96 7. ',2 7.61 7.93 8.25 8.46 6.94 7.37 7.56 7.87 8 21 8.42 6.39 7 27 7.43 7.75 3.12 8.36 6 99 7.47 7.67 7.97 8.28 8.48 6.98 7.46 7.65 7.96 8.27 8.47 6.96 7.42 7.61 7.92 8.24 8.45 7 00 7.50 7.70 8.00 8.30 8.50 7.00 7.50 7.70 8.00 8.30 8.50 6 95 6.97 6.98 7.40 7 45 7 47 7.59 7 65 7.67 7.91 7.96 7.98 8.24 8.27 8.28 8.45 8.48 8.49 Effluent pH * 6.0 Alk 6.77 6 89 6.94 7.03 7.27 7.38 7.16 7.45 7 57 7 44 7.79 7 90 7.89 8.15 8.23 8.18 8.38 8.44 Effluent pH = 6.0 AH 6.66 6.83 6.90 6.86 7.15 7 31 6.94 7.30 7.49 7.12 7 63 7 82 7 51 8.04 8.17 7.89 8.28 8.39 Effluent pH = 6.0 Alk 6.48 6.71 6 83 6.60 6.94 7 16 7.64 7.04 7.31 6.73 7 28 7.65 6.89 7.73 8.06 7.10 8.07 8.30 Effluent pH <• 6.5 Alk 6 93 6.97 6.98 7.34 7.43 7.46 7.53 7.63 7.66 7.85 7.94 7.96 8.19 8.25 8.27 8.40 8.45 3.47 Effluent pH = 6.5 Alk 6.87 6.94 6.97 7.22 7.37 7 43 7.39 7.57 7.63 7.72 7.89 7.94 8.09 8.22 8 26 8.33 8.43 8.46 Effluent pH » 6.5 Alk 6.78 6.89 6.94 7.04 7.27 7.17 7.15 7.44 7.56 7.41 7.77 7.88 7.84 3.13 8.21 8.12 8.35 8.42 Effluent pH = 9.0 Alk 7.04 7 01 7.00 7.51 7.50 7.50 7.70 7.70 7.70 8.00 8.00 8.00 8.30 8.30 8.30 8.50 8.50 8.50 Effluent pH * 9.0 Alk 7.03 7.03 7.01 7.54 7.51 7.50 7.71 7.70 7.70 8.00 8.00 8.00 8.30 8.30 3.30 8.50 8.50 8.50 Effluent pH = 9.0 Alk 7.0 7.5 7.7 8.0 8.3 8.5 7.10 7.56 7.72 8.00 8.30 8.50 7 04 7.52 7 71 8.00 8.30 8.50 7.02 7.51 7.70 8.00 8.30 8.50 7.01 7.00 7.70 8.00 8 30 3 50 7.01 7.50 7 70 8.00 8.30 8.50 7.11 7 04 7.02 7.56 7 52 7.51 7.71 7.70 7 70 8 00 8.00 8.00 8.30 8.30 8 30 8.50 8.50 8.50 = 0.1 6.99 7 43 7.63 7 98 a. 29 8.49 • 0.6 6.96 7.42 7.61 7.93 8.25 8.46 = 1.0 6.93 7.36 7.56 7 83 8.21 8.42 = 2.0 6.83 7.25 7.43 7.77 8 14 8.37 = 0.5 6.98 7.47 7.67 7.97 8.27 8.47 = 1.0 6.98 7.45 7.65 7.96 8.27 8.47 - 2.0 6.96 7.41 7.61 7.92 8.23 8.44 =• 2.0 7.00 7.50 7.70 8.00 8.30 8 50 = 4.0 7.01 7.50 7.70 8.00 8.30 8.50 = 6.0 7.01 7.50 7.70 8.00 8.30 8.50 100 6 99 7.48 7 63 7.99 8.29 8.49 6.97 7.44 7.63 7.95 8.26 3.47 6.95 7.39 7.59 7.91 8.23 8.44 6 90 7.31 7.50 7.83 8.13 8.40 6 99 7 48 7.67 7.98 8.28 8.48 6.98 7.46 7.66 7.97 8.28 8.48 6.97 7.43 7.63 7.94 8.25 8.45 7.QO 7.50 7.70 8.00 8.30 8.50 7.00 7.50 7.70 8.00 8.30 8.50 7.01 7.50 7.70 8 00 8.30 8.50 25°C 10 6.95 7.42 7.62 7.94 8.25 8 46 6.77 7.08 7.24 7.60 8.02 8.27 6 67 6.90 7 01 7.29 7.76 8.06 6 50 6.64 6.70 6.')j 7.11 7.48 6.93 7.37 7.56 7.88 8.20 8.40 6.38 7.26 7.45 7.80 8.14 8.36 6.79 7.08 7.23 7.55 7.96 8.20 7.04 7.51 7.70 8.00 8.30 8.50 7.08 7.53 7.70 8.00 8.30 3.50 7 11 7.54 7.70 8.00 8.30 8.50 Initial Dl 25 50 6 93 7 46 7.66 7.97 8.25 8.48 6.89 7.31 7.51 7 35 8.19 8.41 6.84 7.20 7.38 7 73 8.10 8.32 5.72 6.99 7.12 7.45 7.91 8.18 6.97 7.44 7.64 7.94 8.2C 8.44 6.94 7.40 7.60 7.92 8.24 8.44 6.90 7.30 7.49 7.82 8.16 8.36 7.01 7.50 7.70 8.00 8.30 8.50 7.03 7.51 7.70 8.00 8.30 3 50 7.05 7.51 7 70 8.00 8.30 8.50 6.99 7 48 7.68 7.98 8.29 8.49 6.94 7.40 7.60 7.93 8.24 8.45 6.91 7.33 7.53 7.86 8.19 8.40 6 84 7.20 7.39 7.75 8.12 8.35 6.98 7.46 7.66 7.96 8.26 8.46 6.97 7.45 7.65 7.96 8.27 8.47 6.94 7.39 7.59 7.90 8.22 8.42 7.00 7.50 7.70 8.00 8.30 8.50 7.01 7.50 7.70 8.00 3.30 8.50 7.02 7.50 7.70 8.00 8.30 8.50 ution 75 6,99 7.48 7.68 7.99 8.29 8.49 6.96 7 43 7 64 7.95 8.26 8.47 6.93 7.38 7.58 7.90 8.22 8.42 6.88 7.29 7.49 7.84 8.18 8.40 6.98 7.47 7 67 7.97 8.27 8.46 6.98 7 46 7.66 7.97 8.28 8.48 6.96 7.42 7.62 7.93 8.24 8.43 7.00 7.50 7.70 3.00 8.30 8 50 7.01 7.50 7.70 8.00 8 30 8.50 7.01 7.50 7 70 8.00 8.30 8.50 100 6.99 7.49 7.69 7 99 8.29 8.49 6.97 7.45 7.65 7.96 8.27 8.47 6.95 7.41 7.61 7.92 8.23 3.43 6.91 7.34 7.54 7.88 3.21 8.42 6.99 7.48 7.67 7.97 8.27 8.46 6.98 7.47 7.67 7.98 8.28 8.48 6.97 7.44 7.64 7.94 8.25 8.44 7.00 7.50 7.70 8.00 8.30 8.50 7.00 7.50 7.70 8.00 8.30 8.50 7.01 7.50 7.70 8.00 8.30 8.50 Note Value-, are shown to 2 decimal places to allow interpolation but should be rounded to 1 decimal plate for compdrison to s tandards. 346 ------- EXAMPLE VI-13 A wastewater treatment plant receives alkaline waste process water, and because of the low level of treatment received in the plant, effluent pH values as high as 11.1 units have been observed. The effluent wastewater is discharged into a water body where the pH standard permits a 0.2 unit deviation from ambient at the completion of initial dilution. Determine if the standard is violated by the discharge. The required pertinent data are: pH = 8.3 a Alka = 2.3 meq/1 a Alke = 2.0 meq/1 CKW = 6.3 x 10~14, for the ambient water K.. = 10~7 , for the wastewater W CK, = 8xlO~7,for the ambient water a»i K = 5xlO~7, for the wastewater a, i 'K = 4.68xlO~ , for the ambient water a,2 K = 0.5xlO"10, for the wastewater a,2 Sa = 20 The dissociation constants for the wastewater, a1} and cx2, are: IP"11-1 x 5 x IP"7 (10"11'1)2 + 10"11'1 x 5 x 10'7 + 5 x 10"7 x 0.5 x 10"10 = .137 5 x 10'7 x 0.5 x 10'10 a2 = _ = .863 (lO'11-1)2 + 10'11-1 x 5 + 10'7 -H 5 x 10~7 x 0.5 x 10~: 10 347 ------- The total inorganic carbon of the wastewater is: .002 - -^~Y + 10"lla Ct = = 0.000398 mole/1 e 0.137 + 2 x .863 The dissociation constants for the ambient water are: 10'8"3 x 8 + 10~7 —— (10-8-3)2 + 10-8-3 x 8 x KT7 + 8 x ID'7 x 4.68 x HT10 and a2 = 0.085 The total inorganic carbon content is: 6.3 x lO'1" 0.0023 — + 10"8'3 "a .909 + 2 x 0.085 The final alkalinity and inorganic carbon are: Ct = - = .00212 mole/1 0.002 - 0.0023 Alk, = 0.0023 + - = 0.00229 eq/l f 20 0.000398 - 0.00212 Ct = 0.00212 + - = 0.0020 mole/1 lf 20 Using Equation VI-74, the alkalinity is calculated for the range of pH values tabulated below, beginning at 8.3 and incrementing by 0.1 units. 348 ------- £H Alkalinity, eg/1 8.3 0.00217 8.4 0.00222 8.5 0.00228 8.6 not needed 8.7 not needed 8.8 not needed The actual and calculated alkalinities match at a pH barely exceeding 8.5. Since this slightly is more than 0.2 units above ambient, the pH standard is violated. The pH problem that results from this discharge could be mitigated in a number of ways, such as increasing initial dilution, or by treating the wastewater in order to lower the effluent pH. END OF EXAMPLE VI-13 6.5.5 Dissolved Oxygen Concentration Following Initial Dilution Dissolved oxygen standards in estuarine and coastal waters can be quite stringent. For example, the California Ocean Plan (State Water Resources Control Board, 1978) specifies that: "The dissolved oxygen concentration shall not at any time be depressed more than 10 percent from that which occurs naturally, as the result of the discharge of oxygen demanding waste materials." Since dissolved oxygen concentrations can naturally range as low as 4.0 to 5.0 mg/1 at certain times of the year in estuarine or coastal waters, allowable depletions under these conditions are only 0.4 to 0.5 mg/1. The dissolved oxygen concentration following initial dilution can be predicted using the following expression: 349 ------- DO, = DO + • a DO - IDOD - DO e a Sa (VI-75) where DOf - final dissolved oxygen concentration of receiving water at the plume's trapping level, mg/1 D0a = ambient dissolved oxygen concentration averaged from the diffuser to the trapping level, mg/1 D0e = dissolved oxygen of effluent, mg/1 IDOD - immediate dissolved oxygen demand, mg/1 Sa = initial dilution. The immediate dissolved oxygen demand represents the oxygen demand of reduced substances which are rapidly oxidized during initial dilution (e.g. sulfides to sulfates). The procedure for determining IDOD is found in standard methods (APHA, 1976). IDOD values are often between 1 and 5 mg/1, but can be considerably higher. When the effluent dissolved oxygen concentration is 0.0 mg/1 and IDOD is negligible (which is a common situation), Equation VI-75 simplifies to: °°f = °°a I1 -7: (VI-76) The ambient dissolved oxygen concentration which appears in Equations VI-75 and VI-76 is the concentration in the water column averaged between the location of the diffuser and the trapping level, while the final dissolved oxygen concentration is referenced to the plume's trapping level. 350 ------- The dissolved oxygen concentration can change significantly over depth, depending on the estuary or coastal system as well as on seasonal influences (e.g. upwelling). As the plume rises during initial dilution, water from deeper parts of the water column is entrained into the plume and advected to the plume's trapping level. If the discolved oxygen concentration is much lower in the bottom of the water column than in the top, the low dissolved oxygen water is advected to a region formerly occupied by water containing higher concentrations of dissolved oxygen, and then a "pseudo" dissolved oxygen depletion results, solely caused by entrainment and advection and not consumption of oxygen-demanding material. The following example illustrates this process. EXAMPLE VI-14 Puget Sound, located in the northwest corner of the state of Washington, is a glacially carved, fjord-type estuary. The average depth of water is about 100 m (330 ft). During periods of upwelling, low dissolved oxygen water enters the estuary at depth and produces a vertical dissolved oxygen gradient throughout much of the estuary. In Commencement Bay, near Tacoma, dissolved oxygen profiles similar to the one shown in Table VI-23 have been observed. Suppose the trapping level is 43 ft (13 m) above the bottom and the minimum initial dilution is 28. Find the final dissolved oxygen concentration and calculate the percent depletion. The dissolved oxygen concentration varies significantly over depth, from 5.0 mg/1 at the bottom to 7.8 mg/1 at the water's surface. The average concentration over the plume's trapping level is: 5.0 + 6.1 =5.6 mg/1 Using Equation VI-76, the final dissolved oxygen concentration at the trapping level is: DO, = 5.6 I 1 ) = 5.4 mg/1 ), = 5.6 f 1 |=5.' f \ 28 / 351 ------- TABLE VI-23 DISSOLVED OXYGEN PROFILE IN COMMENCEMENT BAY, WASHINGTON Depth ft(m) 0 (0) 3 (1) 7 (2) 10 (3) 16 (5) 23 (7) 33 (10) 49 (15) 66 (20) 98 (30) 108 (33) Temperature, °C 14.0 12.0 12.0 11.7 11.7 11.7 12.5 13.5 11.5 11.5 11.5 Dissolved Oxygen, mg/1 7.8 7.7 7.6 7.4 7.2 7.0 6.8 6.5 6.1 5.3 5.0 352 ------- Compared to the ambient concentration at the trapping level (6.1 mg/1), the percent depletion is: 6>1 " 5'4 x 100 = 11 percent 6.1 Compared to the average over the height of rise, the percent depletion is only: 5.6 - 5.4 x 100 = 4 percent 5.6 END OF EXAMPLE VI-14 In contrast to the deep estuaries on the west coast of the United States, those on the east coast are quite shallow. In the Chesapeake Bay, the largest east coast estuary, water depths are often in the 20- to 30-ft (6 to 9 m) range, with channels as deep as 60 to 90ft (18 to 27 m) in places. Because of the shallow water depths, initial dilution is often limited by the depth of the water and can be 10 or less at times of low ambient current velocity. 6.5.6 Far Field Dilution and Pollutant Distribution After the initial dilution process has been completed, the wastefield becomes further diluted as it migrates away from the ZID. Since concentrations of coliform organisms are often required not to exceed certain specified values at sensitive locations (e.g. public bathing beaches), a tool is needed to predict coliform ,(or other pollutant) levels as a function of distance from the ZID. This can be accomplished by solving the following expression: 353 ------- u 3x = £ 3y*~ " kC (VI-77) where C = pollutant concentration u = current speed £y = lateral turbulent diffusion coefficient k = pollutant decay rate. Figure VI-32 shows how the sewage field spreads laterally as a function of distance from the ZID. The concentration within the wastefield, C(x,y), depends on both x and y, with the maximum concentrations occurring at y = 0,for any x value. It is the maximum concentration C(x,y = 0) which is of interest here. Solving Equation VI-77, the maximum concentration as a function of distance x is: = C + exp-^ (VI-78) where DS = dilution attained subsequent to the initial dilution and is a function of travel time and all other symbols have been previously defined. The subsequent dilution is unity when x = 0 (i.e. at the completion of initial dilution), so C = C^ at x = 0, as required. In many instances, the background concentration is negligible, so that Equation VI-78 simplifies to: 354 ------- Line source Sewage field FIGURE VI-32 PLAN VIEW OF SPREADING SEWAGE FIELD 355 ------- cf C = — exp (-kt) (VI-79) Subsequent dilution gradually increases as the wastefield travels away from the ZID and depends on mixing caused by turbulence, shear flows, and wind stresses. Often, dilution caused by lateral entrainment of ambient water greatly exceeds that caused by vertical entrainment. This is assumed to be the case here. In open coastal areas, the lateral dispersion coefficient is often predicted using the so-called 4/3 law (Brooks, 1960), where the diffusion coefficient increases as the 4/3 power of the wastefield width. In mathematical form: e = e I —1_ i / 3 1 ' ' (VI-80) where £Q = diffusion coefficient when L = b L = width of sewage field at any distance from the ZID b = initial width of sewage field. The initial diffusion coefficient can be predicted from: eo = O.OOlbVa where e = initial diffusion coefficient, ft2/sec 356 ------- b = initial width of sewage field, ft. Based on Equation VI-80, the center!ine dilution, D , is given by: D = erf 1.5 1 + I/ -1 (VI-82) where t = travel time and erf denotes the error function. The 4/3 law is not always applicable and in confined estuaries might overestimate the diffusion coefficient. Under these circumstances, it is more conservative to assume the diffusion coefficient is a constant. Equation VI-81 can be used to estimate the constant diffusion coefficient, unless the user has better data. Under these circumstances, the subsequent dilution is expressible as: Ds = erf 1 b2 \ 16 £ t \ ° 1 l/2 -1 (VI-83) Equations VI-82 and VI-83 are cumbersome to use, especially if repeated applications are needed. To facilitate predicting subsequent dilutions, values of DS are tabulated in Table VI-24 for different initial widths (b) and travel times (t). The initial sewage field widths range from 10 to 5,000 feet and travel times range from 0.5 to 96 hours. 357 ------- TABLE VI-24 SUBSEQUENT DILUTIONS* FOR VARIOUS INITIAL FIELD WIDTHS AND TRAVEL TIMES 00 Travel Time(hr) 0.5 1.0 2.0 4.0 8.0 12. 24. 48. 72. 96. 10 2.3/ 5. 3. I/ 13. 4.3/ 32. 6. I/ 85. 8.5/>100. 10. />100. 15. />100. 21. />100. 26. />100. 29. />100. 50 5 1.5/ 2.0 2.0/ 3.9 2.7/ 8.5 3.7/ 21. 5.2/ 53. 6.3/ 95. 8.9/>100. 13. />100. 15. />100. 18. />100. Initial Field 100 1.3/ 1.6 1.6/ 2.6 2.2/ 5.1 3.0/ 11. 4. I/ 29. 5. I/ 50. 7. I/ 100. 10. />100. 12. />100. 14. />100. Width (ft) 500 l.O/ 1.1 1.21 1.3 1.4/ 1.9 1.9/ 3.5 2.5/ 7.3 3.0/ 12. 4.2/ 30. 5.9/ 80. 7.3/>100. 8.4/>100. 1000 l.O/ 1.0 l.l/ 1.1 1.2/ 1.5 1.5/ 2.3 2.0/ 4.4 2.4/ 6.8 3.4/ 16. 4.7/ 41. 5.8/ 73 6.6/100. 5000 l.O/ 1.0 l.O/ 1.0 l.O/ 1.0 l.l/ 1.2 1.4/ 1.7 1.6/ 2.3 2. I/ 4.4 2.8/10. 3.4/17. 3.9/24. * The dilutions are entered in the table as Nj/N2, where Nj. is the dilution assuming a constant diffusion coefficient, and N2 is the dilution assuming the 4/3 law. ------- The dilutions presented in the table reveal that as the initial field width increases, the subsequent dilution decreases for a given travel time. For a wider wastefield, a larger time is required to entrain ambient water into the center of the wastefield, so dilutions are lower. This illustrates that a tradeoff exists between large diffusers where initial dilution is high but subsequent dilution low, and small diffusers where initial dilution is low and subsequent dilution high. The table also reveals that the predicted dilutions are significantly different, depending on whether Equation VI-82 or VI-83 is used. In many cases likely to be evaluated by users of this document, the 4/3 law might overestimate subsequent dilution, even if the outfall is in coastal waters. To attain the subsequent dilutions predicted by the 4/3 law at large travel times, a significant amount of dilution water must be available. Since many outfalls, particularly small ones, are often not too far from shore, the entrainment rate of dilution water can be restricted by the presence of the shoreline and the depth of the water. The wastefield from diffusers located further offshore might entrain water at a rate corresponding to the 4/3 law for an initial period of time. As the wastefield widens significantly, the rate of entrainment could decrease, and the 4/3 law no longer obeyed. When travel times are small (e.g. 12 hours or less), there is less discrepancy between the two methods of calculating subsequent dilution, except for the very small initial wastefield widths. EXAMPLE VI-15 Figure VI-33 shows an outfall which extends about one mile offshore. At the end of the outfall is a multiport diffuser, 800 feet in length. Occassionally, fecal coliform bacteria counts as high as 10,000 MPN/100 ml have been detected in the effluent of the treatment plant. The allowable fecal coliform level at the shellfish harvesting area inshore of the diffuser is 70 MPN/100 ml. Typically, the ambient current is parallel to shore so that effluent is not carried onshore. However, when 359 ------- CO en o shellfish harvesting 60 •120 . 0 I contours in feet 1 nautical miles J •180 1.5 kilometers FIGURE VI-33 OUTFALL LOCATION, SHELLFISH HARVESTING AREA, AND ENVIRONS ------- wind conditions are right, onshore transport has been observed, and the sustained transport velocity is 4 cm/sec (0.13 ft/sec). Determine whether the coliform standard is likely to be violated or not. Other information needed are: t coliform decay rate = 1.0/day t minimum initial dilution = 35. The width of the diffuser is 800 feet and will be used as the initial field width. Note, however, that the diffuser is not exactly perpendicular to shore, so that the initial field width is probably less than 800 feet in the travel direction. Using 800 feet is conservative because subsequent dilution will be somewhat lower under this assumption. The coliform count following initial dilution is, using Equation VI-76: 10000 C, = - = 290 MPN/100 ml f 35 The travel time to the shore is: 5280 = 11 hours 0.13 x 3600 Interpolating from Table VI-24, the subsequent dilution is about 2.6. Using Equation VI-79, the coliform concentration at the shoreline is: 290 I 11 , C = exp - 1 x — =70 MPN/100 ml 2.6 24 ' The predicted coliform count is equal to the water quality standard. Since the subsequent dilution was conservatively estimated, it is possible that actual coliform counts will be less than 70 MPN/100 ml. However, the 361 ------- prediction does indicate that careful monitoring of coliform levels at the shoreline is needed to see that the standard is not violated. Since shoreward transport of effluent is infrequent, sampling has to be conducted at times when the transport is shoreward; otherwise detected coliform levels might not represent worst-case conditions. END OF EXAMPLE VI-15 6.5.7 Farfield Dissolved Oxygen Depletion Oxygen demanding materials contained in the effluent of wastewater treatment plants can produce dissolved oxygen deficits following discharge of the effluent into receiving waters. A method will be presented here to predict the depletion following discharge from a marine outfall. The most critical cases occur when the plume and wastefield remain submerged, so that reaeration does not occur. The analysis presented here is applicable to submerged plumes only. When the wastefield is mixed uniformly across the estuary, the methods presented earlier in Section 6.4.5 are applicable. The oxygen-demanding materials in the wastewater are the sum of the carbonaceous and nitrogenous materials (CBOD and NBOD, respectively). It is possible that the nitrogenous demand might not be exerted if a viable background population of nitrifiers is absent from the receiving water. Under these circumstances, the wastefield is likely to be dispersed before the nitrifying population can increase to numbers capable of oxidizing the NBOD. The user can perform analyses with and without NBOD exertion and then determine whether NBOD is significant or not. If it is, it is suggested that some sampling be conducted to find out whether nitrification is occurring. The dissolved oxygen concentration in the receiving waters can be expressed as a function of travel time as follows: 362 ------- DO, - DO I O D0(t) = D0 a f D, [l-exp(-Kt)] s (VI-84) where D0(t) = dissolved oxygen concentration in a submerged wastefield as a function of travel time t, mg/1 DO = ambient dissolved oxygen concentration, mg/1 a DOf = dissolved oxygen concentration following initial dilution (see Equation VI-75) = BOD decay rate Lf = ultimate BOD concentration above ambient at the completion of initial dilution D = subsequent centerline dilution Equation VI-84 expresses the dissolved oxygen deficit which arises due to an initial deficit at the completion of initial dilution (D0f-D0a) plus that caused by elevated BOD levels in the water column (If). The elevated BOD level is either the CBOD or sum of CBOD and NBOD. The initial dissolved oxygen deficit tends to decrease at longer and longer travel times because subsequent dilution increases. However, BOD is being exerted simultaneously and tends to cause the dissolved oxygen level to drop. Depending on the particular case being analyzed, one influence can dominate the other over a range of travel times so that a minimum dissolved oxygen level can occur either immediately following initial dilution, or at a subsequent travel time. The following example illustrates both cases. 363 ------- EXAMPLE VI-16 A municipal wastewater treatment plant discharges its effluent through an outfall and diffuser system. The maximum daily CBOD value is 270 mg/1, and the critical initial dilution is 114. Limited analyses have been performed on IDOD and the results vary widely, from 0 to 66 mg/1. The length of the diffuser is 500 m (1,640 ft) and can be used as the initial sewage field width. Determine the dissolved oxygen deficit produced by the discharge, assuming the wastefield remains submerged and the ambient dissolved oxygen concentration is 7.0 mg/1. The BOD concentration at the completion of initial dilution is: 270 114 = 2.4 mg/l,BODc = 3.5 mg/1, BOD-ultimate The dissolved oxygen concentration at the completion of initial dilution is (from Equation VI-75): D0f = 7.0 + or 0.0 - 66. - 7.0 114 = 6.4 mg/1, when IDOD = 66 D0f = 7.0 + 0.0 - 0.0 - 7.0 114 = 6.9 mg/1, when IDOD = 0 Note that the IDOD of 66 mg/1 produces a deficit of 0.6 mg/1. Since values of IDOD vary widely due to the limited analyses, the far field oxygen depletion curves will be calculated for the following three IDOD's: 0, 40, and 66 mg/1. A BOD decay rate of 0.2/day is used. When IDOD = 66 mg/1, the following oxygen depletions are predicted: 364 ------- Travel Time(hr) 1 4 8 12 24 48 72 96 Ds(Table VI-24) 1. 1.4 1.9 2.3 3.2 4.6 5.5 6.3 DVDOt (Equation VI-84) 0.6 0.5 0.4 0.4 0.4 0.4 0.4 0.4 These results are plotted in Figure VI-34 (Curve A), along with the cases for IDOD = 40 mg/1 (Curve B), and IDOD = 0.0 mg/1 (Curve C). When the IDOD is 66 mg/1, the maximum dissolved oxygen deficit is 0.6 mg/1 and occurs at the completion of initial dilution (a travel time of 0.0 hr). Thus, the processes which occur during initial dilution are more significant than the subsequent BOD exertion. Curve C (IDOD = 0.0 mg/1) shows the opposite situation: farfield BOD exertion is primarily responsible for the maximum oxygen depletion of 0.3 mg/1. The middle curve (Curve B) shows the case when the oxygen depletion remains relatively constant over time and both the near field and farfield processes are important. In summary, when the IDOD is above 40 mg/1, in this example the maximum oxygen depletion is controlled by the processes occurring during initial dilution. When IDOD is below 40 mg/1, BOD exertion in the far field is primarily responsible for the oxygen depletion. For primary treatment plants, IDOD values of 66 mg/1 are atypical; values from 1 to 10 mg/1 are much more common. Depending on whether the state dissolved oxygen standard is violated by Curve A, the user might need to make further IDOD determinations to firmly establish the true range of IDOD values. END OF EXAMPLE VI-16 365 ------- CD C 73 m OJ Crt cn %i co co co c o co r~ —H m ^3 O > < CD m x r- -< CD —I m m m m -l h—t O CO Dissolved oxygen deficit, mg/l p b CD B CD Q. 01 we CO ro — co - p I p Ko I p CO p Ol I p a> P bo p CD 1 o CO Ol o o CD co Ol 0 o > CO en O) O) o O c 03 0 o c~ -T 3 B 6 o p 3 ------- 6.6 THERMAL POLLUTION 6.6.1 General The presence of one or more major heat sources can have a significant impact on both the local biotic community and local water quality. As a result, consideration of significant thermal discharges by the planner is essential in any comprehensive water quality analysis. Thermal power plants account for the vast majority of both the number of thermal discharges and the total thermal load. However, some industrial processes generate significant amounts of excess heat. The most important of the impacts of heat discharge are: 1. Ecological Effects: Water temperature increases change the productivity of planktonic and many benthic species. As a result local community structures are altered. Many of the species benefited by warmer conditions (e.g. blue green algae) may be considered to be undesirable. In addition, many species can perform certain life cycle functions only within a limited temperature range. Elevated temperatures may prevent some species from completing one or more life stages, thus disrupting the reproductive cycle and destroying the stability of the population. 2. Water Quality Effects: Figure VI-23 showed the relative effect of salinity and ambient temperature on oxygen saturation. From this figure, note that a 10° C* rise in temperature decreases the oxygen saturation concentration by 1.5 to 2.0 mg/1. *Such a rise is common near power plant thermal plumes. 367 ------- Sediment Effects: Estuarine sedimentation rates are increased by increasing local water column temperature. The significance of this increase was discussed by Parker and Krenkel (1970). They concluded that not only are sedimentation rates be increased, but vertical particle size distribution, particle fall velocity, and thus bottom composition are also affected. Beneficial Effects: The effects of thermal discharges are not all negative. It has been shown for example, that marine biofouling is substantially reduced in warmed waters (Parker and Krenkel, 1970). In fact, the recirculation of heated discharge through the condenser has proven to be a less expensive and equally effective method of biofouling control than chlorination for several California coastal power plants. Estuarine contact recreation potentials are increased by increasing local water temperatures, and extreme northern estuaries have reduced winter ice coverage as a result of thermal discharges. 6.6.2 Approach A number of the algorithms which appear in this section were originally prepared by Tetra Tech, (1979) for the Electric Power Research Institute. The thermal screening approach for estuaries is composed of procedures that can be used to evaluate the following standards: • The AT Criterion: The increase in temperature of water passing through the condenser must not exceed a specified maximum. t The Maximum Discharge Temperature Criterion: The temperature of the heated effluent must not exceed a specified maximum. 368 ------- • The Thermal Block Criterion: The cross-sectional area of an estuary occupied by temperatures greater than a specified value must not exceed a specified percentage of the total area. • The Surface Area Criterion: The surface area covered by isotherms exceeding a specified temperature increment (above ambient) must not exceed a specified maximum. • The Surface Temperature Criterion: No discharge shall cause a surface water temperature rise greater than a specified maximum above the natural temperature of the receiving waters at any time or place. Table VI-25 presents a summary of the information needed to apply the thermal screening procedure. Data needed for the AT criterion and the maximum discharge temperature criterion were included earlier in the thermal screening section for rivers and are not repeated here. That the maximum discharge temperature criterion for rivers can be applied to estuaries assumes the intake temperature is near ambient, and that tidal action does not cause significantly elevated temperatures near the intake. 6.6.3 Application The AT criterion and the effluent temperature criterion can be evaluated first following the procedures outlined in the river thermal screening section. The maximum allowable flow rate through the plant, which needs to be identified for use in evaluating those criteria, may not always have a readily determinate upper limit, unlike plants sited on rivers. For estuaries that are essentially tidal rivers, a fraction (say 20%) of the net freshwater flow rate might be used as an upper limit. The remainder of the estuary physical screening procedure consists of evaluating the following three criteria: the thermal block, the isotherm surface area, and the surface water temperature criteria. Because of the complexity of the flow field in estuaries, slack tide conditions have been 369 ------- TABLE VI-25 DATA NEEDED FOR ESTUARY THERMAL SCREENING Variable ATc Dp r u Qp ATtb Atb dtb R W At D, K P c. P s n U Rh n Criteria Where Variable Used All All Thermal block. surface area All Thermal block Thermal block Thermal block Thermal block, surface area Thermal block, surface area Thermal block Thermal block, surface area Thermal block, surface area Thermal block, surface area, surface temperature Thermal block, surface area Thermal block, surface area Thermal block, Thermal block, surface area Thermal block, surface area Definition Temperature rise across the condenser (°F) Diameter of discharge pipe or equivalent diameter of discharge canal (m) Exit velocity of thermal discharge (m/s) Flow rate of discharge (m3/s) Temperature rise in estuary cross section that constitutes a thermal block (°F) Portion of estuarine cross-sectional area that constitutes a thermal block (m2) Average depth of estuary from discharge location to ATtb Isotherm at slack tide (m) Average freshwater flow rate flowing in the estuary past the power plant site (m3/s) Width of estuary at power plant site (m) Cross-sectional area at power plant site (m2) Longitudinal dispersion coefficient (m2/s) Surface thermal transfer coefficient (Btu/m2 -d • °F) Average mass density of ambient water at power plant site (kg/mj) Specific heat of water (Btu/kg • °F) Tidally and cross-sectionally averaged salinity (ppt. °/oo Manning's n (m'/6) Maximum tidal velocity over a tidal cycle (m/s) Hydraulic radium (cross-sectional area divided by wetted perimeter) (m) Default Value 20 -- 5 25% of the estuarine cross-sectional area 70.!,, -- see text discussion 1000 (zero salinity) 22 -- 0.016 - 0.06 __ .. Surface area Isotherm associated with legal surface area constraint (°F) Surface area Average depth under the surface area calculated for the surface area constraint (m) Surface area Legally allowable surface area surrounded by isotherms equalling and exceeding AT (m2) S3 temperature Gravitational constant (m/s2) temperature Mass density of thermal effluent (kg/m3) temperature Depth to centerline of discharge jet (m) temperature Maximum legally allowable surface temperature produced hy a submerged discharge (°F) -dp dz Surface Surface Surface Surface Surface Surface temperature temperature Linear density gradient over water column depth (kg/m3 • m) Mass density of water at depth of submerged discharge (kg/m3) 9.8 4 1000 370 ------- chosen as a basis for computations when possible. It is during these conditions that the effects of plume momentum and buoyancy are propogated the greatest distance across the estuary from the discharge site. It is also during slack tide that the thermal block is most likely to occur because of the absence of an ambient current that normally enhances plume entrainment of ambient water. As the plume spreads across the estuary, the methodology assumes it to be vertically mixed. Although most plumes do not generally exhibit this behavior due to such effects as buoyancy and stratification, this approach will roughly estimate the capacity of the estuary at the power plant location to assimilate the excess heat. In some instances, when the estuary is relatively narrow, the plume may extend across the estuary's entire width. In these cases (guidelines are given later to determine when this occurs) the near field momentum approach can be used. By using the well mixed assumption (even if the actual estuary is stratified) a lower limit on the expected temperature elevation across the estuary is obtained. Slack tide conditions will also be used to evaluate the maximum surface temperature produced by a submerged discharge. Both vertically homogeneous and linearly stratified conditions can be evaluated. 6.6.3.1 Evaluating the Thermal Block Constraint. Based upon momentum considerations, the relationship between the ATy isotherm and the distance (y) it extends from the discharge point is given by (Weigel, 1964): (VI-85) where AT = temperature rise across the condenser (°F) 371 ------- AT = temperature excess at a distance y from the discharge outlet y = distance measured along the jet axis originating at the discharge point (m) yQ = virtual source position (m) The virtual source position is usually about two to ten times the diameter of the discharge orifice. The equivalent diameter of a discharge canal is the diameter of a circle whose cross-sectional area is the same as that of the discharge canal. Brooks (1972) has shown that for round orifices, the virtual source position is approximately six times the orifice diameter. At the virtual discharge position (y = y0) the average excess temperature is approximately 70 percent that at the discharge location. Since one of the assumptions used in developing Equation VI-85 is that momentum is conserved along the jet axis, an upper limit on y must be established to prevent the user from seriously violating this assumption. The upper limit can be chosen to be where the plume velocity has decreased to 1 ft/sec or 0.31 meters per second. This implies that the minimum AT that can be evaluated using the equation is: AT „'min " U where Up = exit velocity of thermal discharge (m/s) (ATy)m-jn = minimum excess temperature that can be evaluated using Equation VI-86 (°F) This constraint generally does not restrict practical application of Equation VI-85. 372 ------- Using the value estimated by Brooks (1972) for the virtual source position, Equation VI-85 can be rewritten as: /ATc \ 2 y= 3DP AT^ 1 *fory - 6DP (AT ) . tb p[ ATtb I tb - v y'nnn The cross sectional area to the ATtb isotherm is (assuming the plume remains vertically mixed): Ac = ytb "dtb (VI-89) where A = cross sectional area measured out to the distance ytb (m2) d , = average water depth over the distance y., (m) If Ac ------- where AT = steady state well mixed excess temperature (°F) In this steady state approach, ATSS can no longer be estimated independently of the estuarine flow field characteristics. The surface transfer coefficient K can be determined by reference to the equilibrium temperature discussion in the river thermal screening section. Although the equilibrium temperature does not appear explicitly in Equation VI-90, its effect is indirectly included since K can not be determined independently of E. In the process of finding K, the ambient surface water temperature of the estuary generally should not be assumed to be at equilibrium because of the combined influence of ocean and river water (TRACOR, 1971), each of which may be at different temperatures. The dispersion coefficient, E[_, is dependent on estuary characteristics. A value obtained from past studies in the vicinity of the power plant site should be used if possible. Alternatively, the methods and data provided earlier in Section 6.4.5 can be used. 6.6.3.2 Surface Area Constraint. The surface area constraint can be evaluated employing the same approach used to evaluate the thermal block constraint. Before beginning, Equation VI-86 should be evaluated to ensure that AT exceeds (AT ) - , since (ATv)m-;n establishes the minimum excess isotherm that can be evaluated using these methods. The distance offshore to the ATsa isotherm (the isotherm associated with the legal surface area constraint) can be found as: ysa - 3Dp I ^- I for y > 6D. <«-91> where 374 ------- ysa = distance offshore at Al"sa isotherm (m) The surface area enclosed by that ATsa isotherm can be estimated as: - 6D W + D - 6Dp I ^ (VI-92) where 2Q When the estuary depth drops off rapidly from the outfall location, an appropriate average depth would be the depth to the bottom of the discharge orifice. If A_ J ss (VI-93) where W = width of estuary (m) d = 1/2 IR/^DX) C2 = 1/2 R/(ADi) + (4WL/(pCpAtD • 24 - 3600)) (WK/(pCpAtD! - 24 • 3600)) and ATSS was given by Equation VI-90. When A. -Aca the surface area constraint is not exceeded. S So 375 ------- 6.6.3.3 Surface Temperature Constraint. This section provides a method for estimating the surface temperature of a buoyant plume resulting from a subsurface discharge. Slack tide conditions and a horizontal discharge configuration are considered. A horizontal configuration should approximate conditions under which the lowest maximum surface water temperature excess is attained. When the ambient water density is constant over depth the following two dimensionless parameter groups are needed: f - ~^- Dp (VI-94) and 1.07 Up F (Froude Number) = v/P - Pp Dpg (VI-95) After calculating G and F, Figure VI-35 can be used to find SQ, the centerline dilution relative to the virtual source position. From this information, the maximum surface temperature elevation can be estimated as: AT urface If ATsurface ------- 4 6 8 10 20 F (Froude Number) 40 60 80 100 FIGURE VI-35 CENTERLINE DILUTION OF ROUND BUOYANT JET IN STAGNANT UNIFORM ENVIRONMENT (AFTER FAN AND BROOKS, 1969) 377 ------- I- 3/ ~D~ = 3'86 r T 8 (VI-97) where 1.07 IL yppp^ c PS P- 0.87 (ps - 2 = maximum height of rise of thermal plume (m) max 3 K \ / -£ = linear density gradient (kg/m3/m) Using Equation VI-97, the maximum rise of the thermal plume can be estimated. If it is less than the depth of water, the plume remains submerged. If, however, z exceeds the water depth, the plume will II Id /\ surface. In this case the methods given previously for the nonstratified case can be used to estimate the maximum surface temperature where the ambient water density should be chosen to be the depth-averaged mean. 378 ------- 6.7 TURBIDITY 6.7.1 Introduction Turbidity is a measure of the optical clarity of water and is dependent upon the light scattering and absorption characteristics of both suspended and dissolved material in the water column (Austin, 1974). The physical definition of turbidity is not yet fully agreed upon, and varies from equivalence with the scattering coefficient (Beyer, 1969), to the product of an extinction coefficient and measured pathlength (Hodkinson, 1968), and to the sum of scattering and absorption coefficients (VandeHulst, 1957). Turbidity affects water clarity and apparent water odor, and hence is of aesthetic significance. It also affects light penetration, so that increased turbidity results in a decreased photic zone depth and a decrease in primary productivity. Turbidity levels in an estuary are likely to vary substantially in both temporal and spatial dimensions. Temporal variations occur as a function of seasonal river discharge, seasonal water temperature changes, instantaneous tidal current, and wind speed and direction. Spatially, turbidity varies as a function of water depth, distance from the head of the estuary, water column biomass content, and salinity level. Much of the complexity in the analysis of turbidity results from different sources of turbidity responding differently to the controlling variables mentioned above. As an example, increased river discharge tends to increase turbidity because of increased inorganic suspended sediment load. However, such an increase curtails light penetration, thus reducing water column photosynthesis. This, in turn, reduces the biologically induced turbidity. Methods employed to monitor turbidity include use of a "turbidimeter". Light extinction measurements are commonly given in Jackson Turbidity Units (JTU) which are based on the turbidity of a standard clay suspension. Once standardized, this arbitrary scale* can be used as a basis to measure changes in turbidity. *The JTU scale is an arbitrary scale since it cannot be directly related to physical units when used as a calibration basis for turbidimeter measurement. 379 ------- The turbidity calibration scale is given in APHA (1980). From a measured change in turbidity a relative change in water quality may be inferred. Estuarine water is almost always extremely turbid, especially when compared to ocean or lake waters. The JTU scale is not the only available turbidity scale. In 1926 Kingsbury and Clark devised a scale based on a Formazin suspension medium which resulted in Formazin Turbidity Units (FTU's). More recently volume scattering functions (VSF) and volume attenuation coefficients have been proposed (Austin, 1974). However, JTU's are still most commonly used as an indicator of estuarine turbidity levels. As a rough indication of the wide variations possible in turbidity, Figure VI-36 shows suspended solid concentrations for the various sub-bays of San Francisco Bay for one year (Pearson, jrb ji]_, 1967). The solid line shows annual mean concentrations while the dashed lines indicate concentrations exceeded by 20% and 80% of the samples taken at each station over the one year time period. These variations at stations located near bay heads (left and right extremities of Figure VI-36) typically exceed 300% of the annual 20th percentile values. Use of extreme high/low values would produce correspondingly larger annual variations. 6.7.2 Procedure to Assess Impacts of Wastewater Discharges on Turbidity or Related Parameters Numerous states have enacted water quality standards which limit the allowable turbidity increase due to a wastewater discharge in an estuary or coastal water body. The standards, however, are not always written in terms of turbidity, but are sometimes expressed as surrogate parameters such as light transmittance or Secchi disk. The following three standards provide illustrations: 380 ------- SOUTH I LOWER CENTRAL! NORTH I SAN PABLO I BAY J/ BAY FIGURE VI-36 MEAN SUSPENDED SOLIDS IN SAN FRANCISCO BAY FROM: PEARSON EI AL,, 1967, PG V-15 381 ------- For class AA water in Puget Sound, State of Washington: Turbidity shall not exceed 5 NTU over background turbidity when the background turbidity is 50 NTU or less, or have more than a 10 percent increase in turbidity when the background turbidity is more than 50 NTU. For class A water in the State of Hawaii: Secchi disk or Secchi disk equivalent as "extinction coefficient" determinations shall not be altered more than 10 percent. For coastal waters off the State of California: The transmittance of natural light shall not be significantly reduced at any point outside of the initial dilution zone. A significant difference is defined as a statistically significant difference in the means of two distributions of sampling results at the 95 percent confidence level. These standards illustrate the need for developing interelationships between turbidity related parameters, since data might be available for one parameter while the state standard is expressed in terms of another. Based on these considerations methods will be presented to: • predict the turbidity in the receiving water at the completion of initial dilution • predict the suspended solids concentrations in the receiving water at the completion of initial dilution • relate turbidity and light transmittance data, and • relate Secchi disk and turbidity data. 382 ------- By treating turbidity as a conservative parameter the turbidity in the receiving water at the completion of initial dilution can be predicted as: where If = turbidity in receiving water at the completion of initial dilution (typical units: JTU) Ta = ambient or background turbidity Te = effluent turbidity S, = initial dilution a Initial dilution can be predicted based on the methods presented earlier in Section 6.5.2. Equation VI-98 can be used, then, to directly evaluate those standards written in terms of maximum allowable turbidity or turbidity increase. An expression similar to Equation VI-98 can be used to evaluate the suspended solids concentration in an estuary following completion of initial dilution. Specifically SSQ - SSa SSf = SSa + _e - * (VI-99) a where SSf = suspended solids concentration at completion of initial dilution, mg/1 SS = ambient suspended solids concentration, mg/1 SSP = effluent suspended solids concentration, mg/1 383 ------- S, = initial dilution a Consider now a situation where light transmittance data have been collected but the state standard is expressed in terms of turbidity. A relationship between the two parameters would be useful. Such a relationship can be developed by first considering the Beer-Lambert law for light attenuation: T. = exp(-ad) d (VI-100) where Td = fraction of light transmitted over a depth d, dimensionless a = light attenuation, or extinction coefficient, per meter d = vertical distance between two locations where light is measured, meters Austin (1974) has shown that the attenuation coefficient is expressible in terms of turbidity as: a = k -JTU (VI-101) where JTU = turbidity, in Jackson turbidity units k = coefficient ranging from 0.5 to 1.0 Combining Equations VI-100 and VI-101 the turbidity is expressible as: JTU = ' Td~ ln Td (VI-102) The increased turbidity ( JTU) is expressible as: 384 ------- (VI-103) where Td2 = light transmittance at the final turbidity = light transmittance at the initial turbidity EXAMPLE VI-17 Vertical profiles of several water quality parameters, including percent light transmittance, have been collected in the vicinity of a municipal wastewater discharge in Puget Sound. Figure VI-37 shows each of the three profiles. If the maximum allowable turbidity increase is 5 NTU, does the discharge, based on the light transmittance profile shown in Figure VI-37, violate this requirement? It is known that the wastefield is submerged between about 10 to 20 m below the water's surface. Light transmittances at these depths are about 18 to 20 percent. Deeper within the water column light transmittances are at background values of about 55 percent. Note that in the top few meters the light transmittances are between 0 and 10 percent. These low transmittances are not due to the wastefield, but rather are caused by a lens of turbid freshwater. Consequently, the following data will be used here: t k =0.5 t d = 1 m (i.e. percent transmittance measured over 1 m) • Td2 = 18 percent • Td = 55 percent 385 ------- • - /o Light transmission 0 10 20 30 40 50 60 70 • - Density crT 14.0 15.5 170 18.5 20.0 21.5 23.0 24.5 A -Salinity °/oo 170 18.5 200 21.5 230 24.5 26.0 27.5 Q J L _ 1 __.... 2- M CD ° W INJ 01' CO CO Ol T \ ^r "^ =c ) ^x_ — - — . -^n^ _ •* ^. ^ ^A \ ^**-^. k \ x \ \\ < L ^-^ 80 26.0 29.0 7 ^ t < j 90 100 27.5 29.5 305 32 5 \ I ^ FIGURE VI-37 WATER QUALITY PROFILE OF SELECTED PARAMETERS NEAR A MUNICIPAL OUTFALL IN PUGET SOUND, WASHINGTON 386 ------- The turbidity increase is: 1n Assuming JTU ancl NTU units are equivalent (EPA, 1979), then the increased turbidity is less than the 5.0 NTU allowable. It is of interest to calculate the percent light transmittance within the plume that would cause a 5 NTU increase in turbidity. Using a typical background light transmittance of 50 percent found in central Puget Sound, the minimum light transmittance (Td ) is computed to be: _, percent for k = 0.5 f4 p " 10.5 5 percent for k = 1.0 Light transmittances as low as 0.5 to 4 percent have been found due to causes other than the plume (e.g. plankton blooms and fresh water runoff), but the lowest light transmittances associated with the plume have been about 18 percent per meter. END OF EXAMPLE VI-17 Secchi disk and turbidity can be related to each other in the following manner. Assume that the extinction coefficient, of visible light (a) is directly proportional to turbidity (T) and inversely proportional to Secchi disk (SD), or: a - kx T (VI-104) and a = SO (VI-105) where ki and k2 are constants which have not yet been specified. These two relationships have theoretical bases, as discussed in Austin (1974) and Graham (1968). Combining those two expressions, the relationship between 387 ------- Secchi disk and turbidity becomes: k2 T = kj SD Typical values of kx and k2 are: k = 0.5 to 1.0, where T is expressed in JTU's k = 1.7 where Secchi disk is expressed in meters Thus Equation VI-106 provides a method of correlating turbidity and Secchi disk data. When state standards are written in terms of Secchi disk, it is convenient to combine Equations VI-98 and VI-106 to yield: 1 1 1 . l + SDe " SDa (VI-107) _ SD- SDa S T a a or SD e IVSDf SDj-a'SDa (VI-108) where SDf = minimum allowable Secchi disk reading in receiving water such that the water quality standard is not violated SDg = ambient Secchi disk reading Sa = minimum initial dilution which occurs when the plume surfaces 388 ------- SDe = Secchi disk of effluent Since Secchi disk measurements are made from the water's surface downward, critical conditions (in terms of the Secchi disk standard) will occur when the initial dilution is just sufficient to allow the plume to surface. It is notable that maximum turbidity or light transmittance impacts of a wastewater plume will occur when the water column is stratified, the plume remains submerged, and initial dilution is a minimum. Under these same conditions, however, Secchi disk readings might not be altered at all, if the plume is trapped below the water's surface at a depth exceeding the ambient Secchi disk depth. EXAMPLE VI-18 A municipality discharges its wastewater through an outfall and diffuser system into an embayment. The state standard specifies that the minimum allowable Secchi disk is 3m. Determine whether the discharge is likely to violate the standard. Use these data: SD = 5 to 10m, observed range S, = 75, minimum initial dilution when the plume surfaces a One method of approaching the problem is to assume that violation of the water quality standard is incipient (i.e. SDf = 3m). Under these conditions the effluent Secchi disk would have to be: SDe -1 = 0.1 m = 4 inches Thus, if the Secchi disk of the effluent exceeds 4 inches, the standards will not be violated even under these critical conditions. It would be a simple matter to measure the Secchi disk of the treated effluent to see whether the standard could be violated or not. END OF EXAMPLE VI-18 389 ------- 6.8 SEDIMENTATION 6.8.1 Introduction Like turbidity, sedimentation is a multifaceted phenomenon in estuaries. As in rivers, estuaries transport bed load and suspended sediment. However with the time varying currents in estuaries, no equilibrium or steady state conditions can be achieved (Ippen, 1966). Additionally, while any given reach of a river has reasonably constant water quality conditions, an estuary can vary from fresh water ( 1 ppt. salinity) to sea water ( 30 ppt. salinity), and from a normally slightly acidic conditon near the head to a slightly basic condition at the mouth. The behavior of many dissolved and suspended sediments varies substantially across these pH and salinity gradients. Many colloidal particles* agglomerate and settle to the bottom. In general, all estuaries undergo active sedimentation which tends to fill them in. It is also true for essentially all U.S. estuaries that the rate of accumulation of sediment is limited not by the available sources of sediment but by the estuary's ability to scour unconsolidated sediments from the channel floor and banks. 6.8.2 Qualitative Description of Sedimentation Before presenting what quantitative information is available concerning sediment distribution in an estuary, a qualitative description of sediment sources, types and distribution will be helpful. Sediment sources may be divided into two general classes: sources external to the estuary and sources internal to the estuary (Schultz and Simmons, 1957). The major sources of sediment within each category are shown below. By far the largest external contributor is the upstream watershed. *Co11oidal particles are particles small enough to remain suspended by the random thermal motion of the water. 390 ------- 1. External: • Upstream watershed • Banks and stream bed of tributaries t Ocean areas adjacent to the mouth of the estuary • Surface runoff from land adjacent to the estuary t Wind borne sediments • Point sources (municipal and industrial) 2. Internal: • Estuarine marsh areas • Wave and current resuspension of unconsolidated bed materials • Estuarine biological activity • Dredging General characterizations of U.S. estuarine sediments have been made by Ippen (1966) and by Schultz and Simmons (1957). Many individual case study reports are available for sediment characterization of most of the larger U.S. estuaries (i.e. Columbia River, San Francisco Bay, Charles Harbor, Galveston Bay, Savannah Harbor, New York Harbor, Delaware River and Bay, etc.). In general, estuarine sediments range from fine granular sand (0.01 in. to 0.002 in. in diameter) through silts and clays to fine colloidal clay (0.003 in. or less in diameter) (Ippen, 1966). Very little, if any, larger material (coarse sand, gravel, etc.) is found in estuarine sediments. Sand plays a relatively minor role in East Coast, Gulf Coast and Southern Pacific Coast estuaries. Usually it constitutes less than 5% by volume ( 25% by weight) of total sediments for these estuaries with most of this sand concentrated near the estuarine mouth (Schultz & Simmons, 1957). By contrast, sand is a major element in estuarine shoaling for the north Pacific estuaries (i.e. Washington and Oregon coasts). These estuaries are characterized by extensive oceanic sand intrusion into the lower estuarine segments and by extensive bar formations near the estuarine mouth. The relative distribution of silts and clays, of organic and inorganic material within different estuaries, and, in fact, the distribution of shoaling and scour areas within estuaries, varies widely. 391 ------- 6.8.3 Estuarine Sediment Forces and Movement As sediments enter the lower reaches of a river and come under tidal influence they are subjected to a wide variety of forces which control their movement and deposition. First, net velocities in the upper reaches of estuaries are normally lower than river velocities. Additionally, the water column comes under the influence of tidal action and thus is subject to periods of slack water. During these periods coarse sand and larger materials settle. The scour velocity required to resuspend a particle is higher than that required to carry it in suspension. Thus, once the coarser particles settle out in the lower river and upper estuarine areas, they tend not to be resuspended and carried farther into the estuary (U.S. Engineering District, San Francisco, 1975). Exceptions to this principle can come during periods of extremely high river discharge when water velocities can hold many of these particles in suspension well into or even through an estuary. Table VI-26 lists approximate maximum allowable velocities to avoid scour for various sizes of exposed particles. Values are approximate and are for unarmored sediment (sediment not protected by a covering of larger material). Sediments are subject to gravitational forces and have size-dependent settling velocities. In highly turbulent water the particle fall velocities can be small compared to background fluid motion. Thus gravitational settling occurs chiefly in the relatively quiescent, shallow areas of estuaries or during periods of slack water. As mentioned earlier, particle settling attains a maximum in each tidal cycle during high water slack and low water slack tides. During periods of peak tidal velocity (approximately half way between high and low water) resuspension of unconsolidated sediment may occur. Thus during a tidal cycle large volumes of sediment are resuspended, carried upstream with flood flow, deposited, resuspended, and carried downstream on the ebb tide. Only those particles deposited in relatively quiescent areas have the potential for long term residence. Compounding this cyclic movement of sediments are seasonal river discharge variations which alter estuarine hydrodynamics. Thus, sediment masses tend to shift from one part of an estuary to another (Schultz and Simmons, 1975). 392 ------- TABLE VI-26 MAXIMUM ALLOWABLE CHANNEL VELOCITY TO AVOID BED SCOUR (FPS) (KING, 1954) Original material excavated Clear water, no detritus Water trans- porting colloidal silts Water trans- porting non- colloidal silts, sands, gravels or rock fragments Fine sand 1-50 Sandy loarr 1.75 Silt loam 2.00 Alluvial silts 2.00 Ordinary firm loam 2.50 Volcanic ash 2.50 Fine gravel 2.50 Stiff clay 3.75 Graded, loam to cobbles 3.75 Alluvial silt 3.75 Graded, silt to cobbles 4.00 Coarse gravel 4.00 Cobbles and shingles 5.00 Shales and hardpans 6.00 2.50 2.50 3.00 3.50 3.50 3.50 5.00 5.00 5.00 5.00 5.50 6.00 5.50 6.00 1.50 2.00 2.00 2.00 2.25 2.00 3.75 3.00 5.00 3.00 5.00 6.50 6.50 5.00 393 ------- As fresh waters encounter areas of significant salinity gradients extremely fine particles (primarily colloidal clay minerals) often destabilize (coagulate) and agglomerate to form larger particles (flocculate). The resulting floe (larger agglomerated masses) then settles to the bottom. Coagulation occurs when electrolytes, such as magnesium sulfate and sodium chloride, "neutralize" the repulsive forces between clay particles. This allows the particles to adhere upon collision (flocculation), thus producing larger masses of material. Flocculation rates are dependent on the size distribution and relative composition of the clays and electrolytes and upon local boundary shear forces (Ippen, 1966, and Schultz and Simmons, 1957). Flocculation occurs primarily in the upper central segments of an estuary in the areas of rapid salinity increase. Movement of sediments along the bottom of an estuary does not continue in a net downstream direction as it does in the upper layers and in stream reaches. In all but a very few extremely well mixed estuaries upstream bottom currents predominate at the mouth of an estuary. Thus, upstream flow is greater than downstream flow at the bottom. This is counterbalanced by increased surface downstream flow. However, net upstream flow along the bottom results in a net upstream transport of sediment along the bottom of an estuary near the mouth. Thus, sediments and floes settling into the bottom layers of an estuary near the mouth are often carried back into the estuary rather than being carried out into the open sea. Consequently, estuaries tend to trap, or to conserve sediments while allowing fresh water flows to continue on out to sea. At some point along the bottom, the upstream transport is counter-balanced by the downstream transport from the fresh water inflow. At this point, termed the "null zone", there is essentially no net bottom transport. Here sediment deposition is extensive. In a stratified estuary this point is at the head of the saline intrusion wedge. In a partially mixed estuary it is harder to pinpoint. Nonetheless, sedimentation is a useful parameter to analyze and will be handles in a quantitative manner beginning with Section 6.8.4. To this point, flow in a fairly regular channel has been assumed. However, in many estuaries geomorphic irregularities exist. Such irregularities (e.g. narrow headlands) create eddy currents on their lee sides. These eddy currents, or gyres, slow the sediment movement and allow 394 ------- local shoaling. Additionally, large shallow subtidal or tidal flatlands exist in many estuaries. Such areas are usually well out of the influence of primary currents. As a result local water velocities are usually low and increased shoaling is possible. Wind and waves also have a major influence on estuarine sediment distribution. Seasonal wind driven currents can significantly alter water circulation patterns and associated velocities. This in turn determines, to a large extent, the areas of net shoaling and scour throughout an estuary. Local wind driven and oceanic waves can create significant scour forces. Such scour, or particle resuspension, is particularly evident in shallow areas where significant wave energy is present at the sediment/water interface. Local wind driven waves are a major counterbalancing force to low velocity deposition in many shallow estuarine areas (U.S. Engineering District, San Francisco, 1975). Finally, oceanic littoral currents (long shore currents) interact with flood and ebb flows in the area of an estuary mouth. Particularly in the Pacific Northwest, sandy sediment fed from such littoral drift is a major source of estuarine sediment, and the interference of littoral drift with normal flood and ebb flows is the major factor creating estuarine bars. Figure VI-38 shows the schematic flow of annual sediment movement through San Francisco Bay. With the exception of the magnitude of annual dredging, this is typical for most U.S. estuaries. The most important thing to observe is the dominance of resuspension and redeposition over all other elements of sediment movement including net inflow and outflow. Also note that there is a net annual accumulation of deposited sediment in the bay. This figure is also helpful in conceptualizing the sediment trap or sediment concentration characteristic of estuaries. In any year, 8-10 million cubic yards flow into the estuary and 5 to 9 million cubic yards flow out. However, over 180 million cubic yards are actively involved in annual sediment transport within the estuary. Figure VI-39 is an idealized conceptualization of the various sediment-related processes in an estuary. It must be remembered that these processes actually overlap spatially much more than is shown and that the 395 ------- processes active at any given location vary considerably over time. NET ANNUAL DEPOSITION FIGURE VI-38 SEDIMENT MOVEMENT IN SAN FRANCISCO BAY SYSTEM (MILLION CUBIC YARDS), FROM: U,S, ENGINEERING DISTRICT, SAN FRANCISCO, 1975) From this qualitative analysis, there are some general statements which can be made. Ippen (1966) drew the following conclusions on the distribution of estuarine sediments: a) The major portion of sediments introduced into suspension in an estuary from any source (including resuspension) during normal conditions is retained therein, and if transportable by the existing currents is deposited near the ends of the salinity intrusion, or at locations of zero net bottom velocity. b) Any measure contributing to a shift of the regime towards stratification causes increased shoaling. Such measures may be: structures to reduce the tidal flow and prism, diversion of additional fresh water into the estuary, deepening and 396 ------- PLAN VIEW MAJOR EDDY DEPOSITION ^CHANNEL BANK DEPOSITION :;...;., AREA OF LOW ENERGY DEPOSITION 4) PROFILE AREA OF MAXIMUM SALINITY GRADIENTS -FLOCCULATION SEDIMENT TRAP AREA Q> NULL ZONE "SETTLING -SEDIMENT MOVEMENT (NET) -WATER COLUMN MOVEMENT HEAVY PARTI CLE SETTLING FIGURE VI-39 IDEALIZED ESTUARINE SEDIMENTATION 397 ------- narrowing of the channel. c) Sediments settling to the bottom of an estuary are generally transported upstream and not downstream. Such sediments may at some upstream point be resuspended into the upper layers and carried back downstream. d) Sediments accumulate near the ends of the intrusion zone and form shoals. Shoals also form where the net bottom velocity is zero (in the null zone). e) The intensity of shoaling is most extreme near the end of the intrusion for stratified estuaries and is lessened in the well mixed estuary. f) Shoals occur along the banks of the main estuarine channel where water is deep enough to prevent wave induced scour and where velocities are reduced from main channel velocities sufficiently to allow settling. Schultz and Simmons (1957) made similar conclusions but added the presence of shoaling at the mouth where flood and ebb currents intercept littoral drift. 6.8.4 Settling Velocities As was stated in the previous section, settling velocities do not play a great role in controlling sedimentation patterns in estuaries as they do in lakes. However, it is informative to assess settling rates for various size particles. The possible size classifications of particles and their general inclusive diameter sizes are shown in Table VI-27 Table VI-28 lists terminal settling velocities for each particle size assuming spherical particles and density of 2.0* in quiescent water. From this table it can be *The density of many inorganic suspended particles is approximately equal to that of sand (2.7 gm/cm3) while that of biomass and organic detritus is usually much closer to that of water and can be assumed to be about 1.1 gm/cm3, 398 ------- TABLE VI-27 SEDIMENT PARTICLE SIZE RANGES (AFTER HOUGH, 1957) Derrick STONE One-man STONE Clean, fine to coarse GRAVEL Fine, uniform GRAVEL Very coarse, clean uniform SAND Uniform, coarse SAND Uniform, medium SAND Clean, well -graded SAND AND GRAVEL Uniform, fine SAND Well -graded, silty SAND AND GRAVEL Silty SAND Uniform SILT Sandy CLAY Silty CLAY CLAY (30 to 50% clay sizes) Collodal CLAY (-2p>50%) PARTICLE SIZE RANGE Inches Millimeters D D . max. mm. 120 12 3 3/8 1/8 1/8 — -- -- — -- -- — -- -- 36 4 1/4 1/16 1/32 1/64 -- -- -- — — — -- -- — max. -- 80 8 3 2 0.5 10 0.25 5 2 0.05 1.0 0.05 0.05 0.01 D . mm. -- 10 1.5 0.8 0.5 0.25 0.05 0.05 0.01 0.005 0.005 0.001 0.001 0.0005 10'6 (After B. K. Hough, Basic Soils Engineering, p. 69, Values listed are approximate) 399 ------- TABLE VI-28 « RATE OF FALL IN WATER OF SPHERES OF VARYING RADII AND CONSTANT DENSITY OF 2a AS CALCULATED BY STOKES1 LAWb'° (MYSELS,1959) Radius mm. 10 1 0.1 0.01 10'3 ID'4 10-5 10"6 io-7 Terminal cm. /sec. (>D (>D (>D 2.2xlO-2 2.2xlO-4 2.2x10-6 2.2xlO~8 2.2xlQ-10 (2.2x10-12) velocity cm./min. 1.3 0.013 1.3x10-4 1.3xlO'6 1.3xlO-8 To-apply to other conditions, multiply the u value by the pertinent density difference and divide it by the pertinent viscosity in centipoises. Values in parentheses are calculated by Stokes' law under conditions where this law is not applicable. c Stokes law states that the terminal velocity is nro- portional to the particle radius squared, the differ- ence in density and inversely proportional to the liquid viscosity. 400 ------- inferred that particles of the medium sand class and coarser probably settle to the bottom within a very short time after entering an estuary. Turning to the other end of the particle size scale of Table VI-28, particles with a diameter of 10" mm fall only 3.1 x 10~ inches per hour in the most favorable environment (calm waters). Such a settling rate is not significant in the estuarine environment. Figure VI-40 shows the quiescent settling rates for particle sizes in between these two extremes since this intermediate size group is of real significance in estuarine management (primarily silts). For particles smaller than those shown in Figure VI-40, gravitational settling is not a significant factor in controlling particle motion. Particles substantially larger than the range shown in Figure VI-40 tend to settle above, or at, the head of an estuary. Combining Figure VI-40 (fall per tidal cycle)** with known segment flushing times (in tidal cycles) the size of particles tending to settle out in each segment can be estimated. If such predictions reasonably match actual mean segment sediment particle size, then this method can be useful in predicting changes in sediment pattern. Anticipated changes in river-borne suspended sediment load by particle size can be compared to areas where each size of particle would tend to settle. This would then identify areas which would either be subject to increased shoaling or reduced shoaling and increased scour. This type of analysis has been more successful when applied to organic detritus material than for inorganic suspended loads. A number of simplifying assumptions have gone into this settling velocity analysis. The most significant of these are: 1. Water column density changes have been ignored. Inclusion of this factor would slightly reduce the settling velocity with increased depth. This effect will be more significant for organic matter because of its lower density. 2. Dispersive phenomena and advective velocities have not been considered. **Based on a 12.4 hour tidal cycle. 401 ------- 3. 4. Table VI-27 and Figure VI-40 are based on the fall of perfectly spherical particles. Non-spherical particles have lower settling velocities. Interference between particles has not been considered. However, in a turbulent, sediment-laden estuary such interference is possible (hindered settling). The analysis of the effect of interference on settling velocities was covered in Chapter V for lakes. This analysis is also basically valid for estuaries. The effects introduced there can be applied to Figure VI-40 velocities to adjust for particle interference. 05 10 15 FALL DISTANCE PER TIDAL CYCLE (FT) FIGURE VI-40 PARTICLE DIAMETER vs SETTLING FALL PER TIDAL CYCLE (12,3 MRS) UNDER QUIESCENT CONDITIONS (SPHERES WITH DENSITY 2,0 6.8.5 Null Zone Calculations It was previously mentioned that substantial shoaling occurs in the area of the null zone. It is possible to estimate the location of this zone, and hence the associated shoaling areas, as a function of water depth and river discharge. In addition to the importance of the null zone to 402 ------- shoaling, Petersone and Conomos (Peterson, ert aj_., 1975) established the biological and ecological importance of this area in terms of planktonic production. The null zone, therefore, is both an area of potential navigational hazard and an area of major ecological importance to the planner. Silvester (1974) summarized the analysis for estimating the location of the null zone with respect to the mouth of an estuary. The basic equation used in this analysis is: S U 2 n _ 1000 _r (VI-109) So 0.7S F2 o n where S = mean salinity (averaged vertically and over a tidal cycle) at the null point (n), (ppt) S = ocean surface salinity adjacent to the estuary in parts per thousand (ppt), Ur = fresh water flow velocity, (ft/sec) g = gravational acceleration = 32.2 ft/sec2, d = estuarine depth, (ft) = densimetric Froude number at the null zone where F is defined by: where 403 ------- Ap/pn = difference between fresh water density and that at the null zone (averaged over the depth of the water column) divided by the density at the null zone. This value may be approximated for estuarine waters by: Combining Equations VI-109 and VI-110 and solving for — yields pn Ap 0.7 * Pn 1000 bn (VI-111) This formulation is particularly good for channels which are either maintained at a given depth (dredged for navigation) or are naturally regular, as "d" represents mean cross section channel depth at the null zone. The use of these equations first requires location of the present null zone. This can most easily be done by measuring and averaging bottom currents over one tidal cycle to locate the point where upstream bottom currents and downstream river velocities are exactly equal, resulting in no net flow. This situation is schematically shown in Figure VI-41. When this point has been established for one set of river discharge conditions, Equation VI-111 can be substituted into Equation VI-110 to calculate Fn. This Fn value is an inherent characteristic of an estuary and can be considered to be constant regardless of the variations in flow conditions or null zone location (Silvester, 1974). With this information and a salinity profile for the estuary (SY /\ plotted against x from x = 0 at the mouth of the estuary to x = L at the head) the location of future null zones may be calculated. Given the new conditions of Ur (changes in river discharge) or of d (changes in channel depth, as by dredging activity), Equation VI-109 will allow calculation of a new Sn. This may be plotted on the salinity profile to caculate the location of a new null zone position. Even though these changes will produce a new estuarine salinity profile, the use of Equation VI-109 and the old (known) salinity profile will produce reasonably good estimates of longitudinal shifts in the location of the null zone. Salinity profiles for 404 ------- Mouth U, '09 .** .JNULLZONE NULL ZONE U0.9 * U " U R = tidally averaged velocity at a depth equal to 0.9 of the water column depth. = river flow velocity FIGURE VI-41 ESTUARINE NULL ZONE IDENTIFICATION 405 ------- appropriate seasonal conditions should be used for each calculation (e.g. low flow profiles for a new low flow null zone calculation). EXAMPLE VI-19 Estimation of Null Ipn e_location An estuary has the tidally averaged salinitv profile shown in the Salinity Table below. Mean channel depth in the area of the existing null zone is 18 feet and the salinity at that point is 10 parts per thousand (ppt). Current (low flow) river discharge velocity is 0.5 ft/sec. Normal winter (high flow) velocity is 1.8 ft/sec. It is desired to know where the null zone will be located in summer and winter if a 30 ft deep channel is dredged up to 70,000 feet from the mouth. SALINITY DATA FOR EXAMPLE VI-19 Dis tance from mouth (1 Salinity, (ppt) 000ft) 5 30 15 28 25 25 35 20 45 13 55 8 65 6 75 4 85 1 From equation VI-43 and equation VI-44 F = U n (Sn) (g) (d) = 0.5 ft/sec/ 1 (7xlO-4) (10 ppt) (32.2 ft/sec2) (18 ft) or, F - 0.248 n 406 ------- From equation VI-109 the null zone salinity with a deeper channel will be: Srt 1000 U2 5=0 r n 5 0.7 F2 gd o n 3 = (1000) (0.5 ft/sec)2 /0.7 (0.248)2 (32.2 ft/sec3) (30 ft) Sn = 6.0 ppt From the prevous tabulation this will occur approximately 65,000 ft from the mouth of the estuary. Under winter flow conditions, 1000 U2 S = - r 0.7F2gd = (1000) (1.8 ft/sec)/O.7 (0.248)2 (32.2 ft/sec2) (30 ft) $n = 77.9 ppt This Sn is greater than ocean salinity and will not actually be encountered. Thus, null zone shoaling will occur at the mouth if it occurs at all. This condition is common for rivers with seasonally variable flow rates. END OF EXAMPLE VI-19 407 ------- REFERENCES Abramovich, G., 1963. The Theory of Turbulent Jets, MIT Press. American Public Health Association, 1976. Standard Methods for the Examination of Water and Wastewater. Fourteenth edition. APHA, AWWA, WPCF, 1980. Standard Methods For the Examination of Water and Wastewater. Fifteenth Edition. APHA, Washington, D.C., 1134 pp. Austin, R.W., 1974. "Problems in Measuring Turbidity as a Water Quality Parameter," Proceedings of Seminar on Methodology for Monitoring the Marine Environment. EPA Environmental Monitoring Series, Number EPA 6QO/4-74-004. Beyer, G.L., 1969. "Turbidimetry and Nephelometry," Encyclopedia of Chemical Technology, New York, pp. 738-798. Brooks, N.H., 1972. Dispersion in Hydrologic and Coastal Environments. California Institute of Technology, Division of Engineering and Applied Science, Report No. KH-R-29. California State Water Resources Control Board, 1978. Water Quality Control Plan for Ocean Waters of California. State Water Resources Control Board Resolution No. 78-2. 15 pp. Carhart, R.A., A.J. Policastro, S. Ziemer, K. Haake, and W. Dunn, 1981. Studies of Mathematical Models for Characterizing Plume and Drift Behavior from Cooling Towers, Volume 2: Mathematical Model for Single-Source (single-tower) Cooling Tower Plume Dispersion. Electric Power Research Institute, CS-1683, Vol. 2, Research Project 906-1. Chen, C.W. and Orlob, G.T., 1975. "Ecologic Simulation for Aquatic Environments", Systems Analysis and Simulation in Ecology, Vol. III. Academic Press, Inc., New York, pp. 475-558. DeFalco, Paul, Jr., 1967. "The Estuary-Septic Tank of the Megalopolis," Estuaries; Ed: G.H. Lauff, American Association for the Advancement of Science, Publication No. 83, pp. 701-707. Duxbury, A.C., 1970. "Estuaries Found in the Pacific Northwest," Proceedings, Northwest Estuarine and Coastal Zone Symposium. Bureau of Sport Fisheries and Wildlife. Dyer, K.R., 1973. Estuaries: A Physical Introduction, John Wiley and Sons, New York. Edinger, J.E., 1971. "Estuarine Temperature Distributions," Estuarine Modeling: An Assessment. Chapter 4, Environmental Protection Agency Water Pollution Control Research Series, No. 16070DZV 02/71. Edinger, J.E. and E.M. Polk, 1969. Initial Mixing of Thermal Discharges into a Uniform Current. Water Center Report #1, Vanderbilt University. 408 ------- Fan, L.N., 1967. Turbulent Buoyant Jets into Stratified or Flowing Ambient Fluids. KH-R-15, W.M. Keck Laboratory, Cal Tech, Pasadena, California. Fisher, H.B., 1968. Methods for Predicting Dispersion Coefficients in Natural Streams, with Applications to Lower Reaches of the Green and Duwamish Rivers, Washington. U.S. Geological Survey Professional Paper 582-A, U.S. Government Printing Office, Washington, D.C. Frick, W.E., 1981a. Projected Area in Plume Modeling. Submitted for publication September 1981. Corvallis, Oregon. Frick, W.E., 1981b. Comparison of PLUME and OUTPLM Predictions with Observed Plumes. Tetra Tech, Inc., Frick, W.E., 1981c. A Theory and Users's Guide for the Plume Model MERGE. Tetra Tech, Inc., Corvallis, Oregon. Frick, W.E., 1980. Findings and Recommendations On the Use and Modification of the EPA Computer Model DKHPLM. Tetra Tech, Inc., Corvallis, Oregon. Frick, W.E. and L.D. Winiarski, 1980. Why Froude Number Replication Does Not Necessarily Ensure Modeling Similarity. In: Proceedings of the Second Conference on Waste Heat Management and Utilization, Miami Beach, Florida. Frick, W.E. and L.D. Winiarski, 1975. Comments on "The Rise of Moist Buoyant Plumes." Journal of Applied Meteorology, Vol. 14, No. 3, page 421. Giger, R.D., 1972. "Some Estuarine Factors Influencing Ascent of Anadromous Cutthroat Trout in Oregon," Proceedings of the Second Annual Technical Conference on Estuaries of the Pacific Northwest. Oregon State University, pp. 18-30. Glenne, B., 1967. "A Classification System for Estuaries," Journal of the Waterways and Harbors Division. February, 1967, pp. 55-61. Goodwin, C.R., E.W. Emmett and B. Glenne, 1970. Tidal Studies of Three Oregon Estuaries. Oregon State University Engineering Experiment Station Bulletin No. 45. Graham, J.J., 1968. Secchi Disc Observations and Extinction Coefficients in the Central and Eastern North Pacific Ocean. Limnology and Oceanography, pp. 184-190. Green, J., 1968. The Biology of Estuarine Animals. University of Washington Press; Seattle, Washington. Hansen, D.V. and M. Rattray, 1966. "New Dimensions in Estuarine Classification," Limnology and Oceanography, Vol. XI(3), pp. 319-326. Hardy, C.D., 1972. Movement and Quality of Long Island Sound Waters, 1971. State University of New York, Marine Sciences Research Center, Technical Report #17. 409 ------- Harleman, D.R.F., 1964. "The Significance of Longitudinal Dispersion in the Analysis of Pollution in Estuaries," Proceedings 2nd International Conference on Water Pollution Research. Tokyo, Pergamon Press, New Harleman, D.F.R., 1971. "Hydrodynamic Model - One Dimensional Models." Estuarine Modeling: An Assessment, Chapter II-3, EPA Water Pollution Control Research Series, No. T5D70 DZV 02/71, pp. 34-90. Harleman, D. and C.H. Lee, 1969. The Computation of Tides and Current in Estuaries and Canals. U.S. Corps of Engineers Committee on Tidal Hydraulics, Technical Bulletin No. 16. Hodkinson, J.R., 1968. "The Optical Measurement of Aerosols," Aerosol Science. Ed: Davies, C.N., Academic Press, Inc., New york, pp. 287-357. Hough, B.K., 1957. Basic Soils Engineering. The Ronald Press Co., New York, pg. 69. Hydroscience, Inc., 1971. Simplified Mathematical Modeling of Water Quality. EPA, Water Quality Management Planning Series, Washington, D.C. Hydroscience, Inc., 1974. Water Quality Evaluation for Ocean Disposal System - Suffolk County, New York. Bowe, Walsh and Associates Engineers, New York. Ippen, A.T., 1966. Estuary and coastline Hydrodynamics. McGraw-Hill Book Company, New York. Jirka, G. and D.R.F. Harleman, 1973. The Mechanics of Submerged Multiport Diffusers for Buoyant Discharges in Shallow Water. Report No. 169, Ralph M. Parsons Laboratory, Department of Civil Engineering, MIT, pg. 236. Johnson, R.G., W.R. Bryant, and J.W. Hedgpeth, 1961. Ecological Survey of Tomales Bay: Preliminary Report of the 1960 Hydrological Survey. University of the Pacific, Pacific Marine Station. Johnson, J., 1973. "Characteristics and Behavior of Pacific Coast Tidal Inlets," Journal of the Waterways Harbors and Coastal Engineering Division, August, 197, pp. 325-339. Ketchum, B.H., 1950. "Hydrographic Factors Involved in the Dispersion of Pollutants Introduced Into Tidal Waters," Journal of the Boston Society of Civil Engineers, Vol. 37, pp. 296-314. Ketchum, B.H., 1955. "Distribution of Coliform Bacteria and Other Pollutants in Tidal Estuaries," Sewage and Industrial Wastes, Vol. 27, pp. 1288-1296. Ketchum, B.H. and D.J. Keen, 1951. The Exchanges of Fresh and Salt Waters in the Bay of Fundy and in Passamaquoddy Bay. Woods Hole Oceanographic Institution, Contribution No. 593, Reference Number 51-98. 410 ------- King, H.W., 1954. Handbook of Hydraulics. Revised by E.F. Brater. McGraw-Hill Book Company, New York, pp. 7-33. McGauhey, P.H., 1968. Engineering Management of Water Quality, McGraw-Hill Book Company, San Francisco. McKinsey, D., 1974. Seasonal Variations in Tidal Dynamics, Water Quality, and Sediment in Alsea Estuary, Oregon State University, Dept. of Civil Engineering, Corvallis, Oregon. Mysels, K.J., 1959. Introduction to Conoid Chemistry, Interscience Publisher, New York, pg. 61. Neumann, G. and W. Pierson, 1966. Principles of Physical Oceanography, Prentice-Hall, Inc., Englewood Cliffs, New Jersey. O'Brien, M.P., 1969. "Equilibrium Flow Areas of Inlets on Sandy Coasts," Journal of the Waterways and Harbors Division, Proceedings of the American Society of Civil Engineers, pp. 43-51. O'Connor, D.J., 1965. Estuarine Distribution of Nonconservative Substances. Journal of Sanitary Engineering Division, ASCE. SA1, pp. 23-42. O'Connor, D.J. and R.V. Thomann, 1971. "Water Quality Models: Chemical, Physical, and Biological Constituents," Estuarine Model ing: An Assessment, Chapter III, EPA Water Pollution ControTTesearch Series No. 16070 DZV 02/71, pp. 102-169. Parker, F.L. and P.A. Krenkel, 1970. CRC Physical and Engineering Aspects of Thermal Pollution, The Chemical Rubber Company Press, Cleveland, Ohio. Pearson, E. ejt aj_., 1967. Final Report: A Comprehensive Study of San Francisco Bay, Volume V: Summary of Physical, Chemical and Biological Water and Sediment Data, U.C. Berkeley Sanitary Engineering Research Laboratory, Report No. 67-2. Perkins, E.J., 1974. The Biology of Estuaries and Coastal Waters, Academic Press, London. Peterson, O.H. et a^., 1975. "Location of the Non-tidal Current Null Zone in Northern San Francisco Bay." Estuarine and Coastal Marine Science, (1975) 3, pp. 1-11. Policastro, A.J., R.A. Carhart, S.E. Ziemer, and K. Haake, 1980. Evaluation of Mathematical Models for Characterizing Plume Behavior from Cooling Towers. Dispersion from Single and Multiple Source Natural Draft Cooling Towers, NUREG/CR-1581, Vol. 1, Argonne National Laboratory, Argonne, Illinois. Pritchard, D.W., 1960. "The Movement and Mixing of Contaminants in Tidal Estuaries," Proceedings of the First International Conference on Waste Disposal in the Marine Environment, University of California, Berkeley. Pritchard, D.W., 1967. "What is an Estuary: Physical Viewpoint," Estuaries. Ed: Lauff, G.H., American Association for the Advancement of Science, Publication No. 83, pp. 2-6. 411 ------- Pritchard, D.W., 1969. Dispersion and Flushing of Pollutants in Estuaries. Journal of Hydraulics Division, ASCE, HY1, pp. 115-124. Pritchard, D.W. and J.R. Schubel, 1971. "What is an Estuary," The Estuarine Environment-Estuaries and Estuarine Sedimentation, American Geological Institute. Rawn, A.M., F.R. Bowerman, and N.H. Brooks, 1960. Diffusers for Disposal of Sewage in Seawater. Journal of the Sanitary Engineering Division, ASCE, SAR, pg. 80. Schubel, J.R., 1971. "The Origin and Development of Estuaries," The Estuarine Environment-Estuaries and Estuarine Sedimentation, American Geological Institute. Schultz, E.A. and H.B. Simmons, 1957. Freshwater-Salt Water Density Current, a Major Cause of Siltation in Estuaries. Commission on Tidal Hydraulics, U.S. Army Corps of Engineers, Technical Bulletin No. 2. Serne, R.J. and B.W. Mercer, 1975. "Characterization of San Francisco Bay Delta Sediments - Crystalline Matrix Study." Dredge Disposal Study of San Francisco Bay and Estuary, Appendix F, U.S. Army U.S. Corps of Engineers, San Francisco, District. Shiraza, M.A. and L.R. Davis, 1976. Workbook of Thermal Plume Predictions: Surface Discharge, USEPA Corvallis Environmental Research Laboratory, Oregon. Silvester, R., 1974. Coastal Engineering, II: Sedimentation, Estuaries, Tides, Effluents and Modeling, Elsevier Scientific Publishing Company, New York. Stommel, H., 1953. "Computation of Pollution in a Vertically Mixed Estuary." Sewage and Industrial Wastes, 25(9), pp. 1065-1071. Streeter, V.L. (Editor-in-Chief), 1961. Handbook of Fluid Dynamics, McGraw-Hill Book Company, Inc., New York, New York. Stumm, W. and J.J., Morgan, 1970. Aquatic Chemistry: An Introduction Emphasizing Chemical Equilibria in Natural Waters, Wiley-Interscience, New York, pp. 507-513. Teeter, A.M. and D.J. Baumgartner, 1979. Prediction of Initial Mixing for Municipal Ocean Discharges, CERL-043. USEPA Corvallis Environmental Research Laboratory, Oregon. Tesche, T.W., W.D. Jensen, and J.L. Haney, 1980. Modeling Study of the Proposed SMUD Geothermal Power Plant: Model Application Protocol. SAI No. 118-E780-11, Systems Applications, Inc., San Rafael, California. Tetra Tech, Inc., 1979. Methodology for Evaluation of Multiple Power Plant Cooling System Effects. Volume: General Description and Screening. Electric Power Research Institute Report EA-1111. Palo, Alto, California 412 ------- Tracer, 1971. Estuarine Modeling: An Assessment For: Water Quality Office, Environmental Protection Agency. U.S. Engineer District - San Francisco, 1975. Draft Composit Environmental Statement for Maintenance Dredging of Federal Navigation Projects in San Francisco Bay Region, California, U.S. Army Corps of Engineers. U.S. Environmental Protection Agency, 1^79. Methods for Chemical Analysis of Water and Wastes, EPA-600/4-79-020. Van de Hulst, H.C., 1957. Light Scattering by Small Particles. John Wiley and Sons, Inc., New York. Winiarski, L.D., and W.E. Frick, 1978. Methods of Improving Plume Models. Presented at the May 2-4, 1978, Cooling Tower Environment 1978 Conference, University of Maryland, College Park, Maryland. Winiarski, L.D. and W.E. Frick, 1976. Cooling Tower Plume Model, EPA-600/3-76-100. USEPA Corvallis Environmental Research Laboratory, Corvallis, Oregon. 413 ------- ------- APPENDIX A MONTHLY DISTRIBUTION OF RAINFALL EROSIVITY FACTOR R Figure A-l - Key Map for Selection of Distribution Curves for Eastern United States Figure A-2a through A-2i - Distribution Curves for Eastern United States Distribution Curves for Hawaii (Figures A-3a through A-3c) Methods for Developing R Distribution Curves for the Western United States A-l ------- > INS FIGURE A-l KEY MAP FOR SELECTION OF APPLICABLE EROSION-INDEX DISTRIBUTION CURVE (WlSCHMEIR AND SMITH, 1965) ------- e-v C1 d ;O m 3> I ro Percent of Annual Erosion Index i\> ^ o> oo o o o o o o o Percent of Annual Erosion Index ro -t> O) oo o o o o o o o -< o CO CO o •— DC O m I m z PO O m > x O E 3 OO CO l . x to ^ c: H t— > — • LO O cn z m co H -JL m co H m Percent of Annual Erosion Index ro -& a) oo O o o o o o o Percent of Annual Erosion Index ro .& cn oo o o o o o o o m a co H m co ------- T3 C 100 80 o ^ UJ 60 ^ 4° H- O - 20 o> o 0 100 4/1 6/1 8/1 Date 10/1 12/1 2/1 4/1 6/1 8/1 Date 10/1 12/1 xlOO a> c 80 o to o 60 40 o c 2/1 4/1 6/1 8/1 Date 10/1 12/1 2/1 4/1 6/1 8/1 Date 12/1 FIGURE A-2e EROSION-INDEX DISTRIBUTION CURVES FOR THE EASTERN UNITED STATES (WlSCHMEIER AND SMITH, 1965) ------- 9-V Percent of Annual Erosion Index Percent of Annual Erosion Index CD d 73 m i ro o r=: 73 —• o CO CO O —i re o m i m z 73 o m > X a a CO CO 2 H X CO ^ cr H (_-i H-i CO O CD Z un m CO Tl o H X m m > CO H m m a GO m CO i i i I I i I I I I M i i i i i Percent of Annual Erosion Index Percent of Annual Erosion Index ------- 9-V Percent of Annual Erosion Index Percent of Annual Erosion Index o cz 73 m i ro a — • o CO CO o — . re o 2 -Z. m i m z 73 a rn > X •z. G C3 CO CO X D3 cn Percent of Annual Erosion Index Percent of Annual Erosion Index rn CO •n o m m > CO H m 73 a oo m CO i i i i i i i i i i i i i i i i i i i ------- 100 6/1 8/1 Date 10/1 12/1 4/1 6/1 8/1 Date 10/1 12/1 100 c 80 D 3 C 0> o l_ 0) 0_ 60 40 20 2/1 19 4/1 6/1 8/1 Date 10/1 12/1 4/1 6/1 8/1 Date 10/1 12/1 FIGURE A-2E EROSION-INDEX DISTRIBUTION CURVES FOR THE EASTERN UNITED STATES (WlSCHMEIER AND SMITH, 1965) ------- > oo x 100 O) •o c c 80 o o TJ C o o D c o t_ a> Q_ 60 o 3 I 40 o £ 20 o L. w °- 0 2/1 100 80 uJ 60 40 20 21 I 4/1 6/1 8/1 Date 10/1 12/1 22 2/1 4/1 6/1 8/1 Date 10/1 12/1 T3 ^ C O 55 o o 3 C C < «4- o c o> o L_ CL C a> o 100 80 60 40 20 100 T3 _C c 80 o 60 40 20 23 2/1 4/1 6/1 8/1 Date 10/1 12/1 24 2/1 4/1 6/1 8/1 Date 10/1 12/1 FIGURE A-2p EROSION-INDEX DISTRIBUTION CURVES FOR THE EASTERN UNITED STATES (WlSCHMEIER AND SMITH, 1965) ------- > xlOO o> c 80 o 60 o 3 4° C o> o i_ o> Q. 20 100 2/1 100 80 CO e UJ o o c c a> o L. a> Q. 60 40 20 0 2/1 4/1 6/1 8/1 Date 10/1 12/1 26 J I I I I I J I 4/1 6/1 8/1 Date 10/1 12/1 a> c 80 o C. Q> O 60 40 20 2/1 x 100 9) c g in o O 80 60 40 = 20 Q> O 4/1 6/1 8/1 Dote 10/1 12/1 2/1 4/1 6/1 8/1 Date 10/1 12/1 FIGURE A-2G EROSION-INDEX DISTRIBUTION CURVES FOR THE EASTERN UNITED STATES (WlSCHMEIER AND SMITH, 1965) ------- 4/1 6/1 8/1 10/1 12/1 4/1 6/1 8/1 10/1 12/1 2/1 4/1 6/1 8/1 Date 10/1 12/1 x 100 _c c 80 o to o uj 60 o I 40 *4- O c 20 0> o 6/1 8/1 Date FIGURE A-2n EROSION-INDEX DISTRIBUTION CURVES FOR THE EASTERN UNITED STATES (WlSCHMEIER AND SMITH, 1965) ------- 100 X 0) •o - 80 c o 'tn o uj 60 c < 40 § 20 i_ ------- I I-J to o '(A 2 UJ o 3 c o s. 100 80 60 40 20 0 80 60 40 20 0 KAUAI, Brydeswood Area Koloa District KAUAI, Southwest Port of Island, Waimeo District 2/1 4/1 6/1 8/1 10/1 12/1 Date 100 80 60 40 20 0 100 80 60 40 20 0 KAUAI, Lihue Area Lihue District MOLOKAI, North Central Part of Island, Hoolehua and Kualapuu Areas 2/1 4/1 6/1 8/1 10/1 12/1 Date 100 80 60 40 20 0 100 80 60 40 20 0 LANAI, Lanai City Area MOLOKAI, South Central Part, of Island, Kaunakakai Area 2/1 4/1 6/1 8/1 10/1 12/1 Date FIGURE A-3A EROSION-INDEX DISTRIBUTION CURVES FOR HAWAII (SOILS TECHNICAL NOTE No, 3, 1974) ------- > 100 80 60 X O) 40 c O "55 o UJ 5 20 c < 0 100 OAHU, Leeward Side of Island o 80 c « 2 60 s. 40 20 OAHU, Windward Side of Island 2/1 4/1 6/1 8/1 10/1 12/1 Date 100 80 60 40 20 0 100 80 60 40 20 0 HAWAII, Western Part of Island ill HAWAII, Eastern Part- vicinity of Hilo, North Hilo, South Hilo, Puna,. Dists. 2/1 4/1 6/1 8/1 10/1 12/1 Date 100 80 60 40 20 100 80 60 40 20 HAWAII, Northern Port of Island, Hamakua District HAWAII, Southern Port Ka'u District 2/1 4/1 6/1 8/1 10/1 12/1 Date FIGURE A-3B EROSION-INDEX DISTRIBUTION CURVES FOR HAWAII (SOILS TECHNICAL NOTE No, 3, 1974) ------- CD C. 33 m I v~M o GO 73 O O f-i CO r~ -< co o m i — i n z: x o z rn — X o > cm O CO i m co c: ^. -\ o — m co TI O > s: > Parcent of Annual Erosion Index o 8 S 8 § Percent of Annual Erosion Index S 03 o ro a> o o CD ro Percent of Annual Erosion Index ro O O) o 8 o o Percent of Annual Erosion Index 8$ 8 CO o o o ro o a Co ro ------- METHODS FOR DEVELOPING R DISTRIBUTION CURVES FOR THE WESTERN UNITED STATES (Conservation Agronomy Technical Note No. 32, 1974) R is significant in portions of this area. Divide the annual R for the location by the average annual precipitation to obtain a factor. Multiply each month's precipitation by this factor to obtain monthly R values. Add the prorated monthly R values to R for the months when snowmelt occurs, to obtain the monthly R values. Compute the monthly accumulative percent. The following example is for Hylton, in Elko County, Nevada. The 2-6 rainfall for this area is 0.9 in. The annual R determined from the Type II curve on Figure III-4, is 18. Annual precipitation average is 12.72 in. Factor is 18 ~ 12.72 = 1.42. Monthly precipitation (water depth) for December through March is 4.92 in. Rg = 4.92 x 1.5 = 7.38. This is prorated, based on local judgment to January 10% or 0.7 February 20% or 1.5 March 50% or 3.7 April 20% or 1.5 Month (1) January February March April May Precipi- tation (Inches Water Depth) (2) 1.18 1.14 1.29 1.49 1.48 R r (3) 1.68 1.62 1.83 2.12 2.10 Rs (4) 0.7 1.5 3.7 1.5 - R* 15} 2.38 3.12 5.53 3.62 2.10 Cumul R .(A) 2.38 5.50 11.03 14.65 16.75 ative °i 10 (7) 0.093 21.6 43.3 57.5 65.8 ^Columns (3) + (4). A-15 ------- Month (1) June July August September October November- December Precipi- tation ( Inches Water Depth) (2) 0.91 0.63 0.52 0.63 1.17 0.97 1.31 Rr 131 1.29 0.89 0.74 0.89 1.66 1.38 1.86 R R* (4) (5) 1.29 0.89 0.74 0.89 1.66 1.38 1.86 Cumul R (6) 18.04 18.93 19.67 20.56 22.22 23.60 25.46 ative 01 lo (7) 70.9 74.4 77.3 80.8 87.3 92.7 100. *Columns (3) + (4). Values in cumulative percent column (7) are the points used in plotting the monthly R distribution curve. f°T A-2, A-3, and A-4 Areas Shown in Figure II1-4 RS is not significant in most parts of these areas. Use the monthly rainfall distribution as the R distribution. Simply accumulate monthly precipitation amounts and divide each by the annual precipitation. The results obtained for each month will be the points for plotting the monthly R distribution curve. For B-1 and C Areas Shown in Figure III-4 R in most parts of these areas is significant. 1. "Multipliers" are used to time average monthly precipitation amounts. Sum the results of multiplications to obtain the "factored annual precipitation". Divide the annual R for A-16 ------- the location by the "factored annual precipitation" to obtain a factor which will be used to convert monthly precipitation amounts to the monthly R values (see the previous section for A-l area). Values of multipliers are: Month(s) Multipliers January, February, March 0.1 April 1.0 May 4.0 June, July, August 7.0 September, October 2.0 November, December 0.1 Add the prorated R values to the months when the snowmelt occurs to obtain the monthly R values. Compute the monthly cumulative percents which are points used in plotting the monthly R distribution curve. The following example is for a hypothetical area which has an annual rainfall factor Rr of 25, and a RS factor of 7.5 (4.94 x 1.5 rounded to 7.5). The 4.94 in. is total precipitation for December. January, February, and March. R factor is prorated to: January 0% or 0 in. February 33.3% or 2.5 in. March 33.3% or 2.5 in. April 33.3% or 2.5 in. A-17 ------- Month (1) January February March April May June July August September October November December Total Month TIT January February March April May June July August September October November December Total Precipi- tation (in.) (2) 1.33 1.14 1.35 1.48 1.43 1.00 0.80 0.78 0.85 1.14 0.92 1.12 13.34 Monthly Rs (6) - 2.5 2.5 2.5 - - - - - - - - 7.5 Multiplier (3) 0.1 0.1 0.1 1.0 4.0 7.0 7.0 7.0 2.0 2.0 0.1 0.1 Monthly R =Rr + Rs (7) 0.11 2.59 2.66 3.74 4.80 5.87 4.69 4.58 1.43 1.91 0.08 0.09 32.5 Factored Monthly pptn. (Col. 2 x Col. 3) (4) 0.13 0.11 0.13 1.48 5.72 7.00 5.60 5.46 1.70 2.28 0.09 0.11 29.81 Cumulati R W 0.1 2.7 5.4 9.1 13.9 19.8 24.5 29.0 30.5 32.4 32.4 32.5 Monthly R * r* (5) 0.11 0.09 0.11 1.24 4.80 5.78 4.69 4.58 1.43 1.91 0.08 0.09 25.0 ve % w> - 8 17 28 43 61 75 89 94 99 100 100 *In this example, the calculated factor value is 0.84 (25 + 29.81). Monthly R is obtained by multiplying each "factored monthly pptn." with 0.84: A-18 ------- For B-2 Area Shown in Figure II1-3 In this area, no R values are needed. Follow the same procedure and use the same set of multipliers as the preceding section for areas B-l and C, except that steps for obtaining monthly R values are not used. The cumulative R and cumulative percent are computed from monthly R (column 5 in the preceding example). REFERENCES FOR APPENDIX A Conservation Agronomy Technical Note No. 32, U.S. Department of Agriculture, Soil Conservation Service, West Technical Service Center, Portland, Oregon, September, 1974. Soils Technical Note No. 3, U.S. Department of Agriculture, Soil Conservation Service, Honolulu, Hawaii, May, 1974. Wischmeier, W.H., and Smith, D.D., "Predicting Rainfall—Erosion Losses from Cropland East of the Rocky Mountains," Agricultural Handbook 282, U.S. Department of Agriculture, Agriculture Research Service, May, 1965. A-19 ------- APPENDIX B METHODS FOR PREDICTING SOIL ERODIBILITY INDEX K Nomograph for Predicting K Values of Surface Soils Using Chemical and Physical Parameters. Nomograph for Predicting K Values of High Clay Subsoils Using Chemical Mineralogical and Physical Parameters. B-l ------- NOMOGRAPH FOR PREDICTING K VALUES OF SURFACE SOIL In 1971 Wischmeier, et al. (1971) presented a soil credibility nomograph derived from statistical analysis of 55 soil types. Five soil parameters are included in the nomograph to predict credibility: percent silt plus very fine sand; percent sand greater than 0.10 millimeter; organic matter content; soil structure; and permeability. Values of the parameters may be obtained from routine laboratory determinations and standard soil profile descriptions. The nomograph is reproduced here as Figure B-l. Description of Factors (Water Resources Administration, 1973) Grain Size Distribution Grain size distribution has a major influence on a soil's credibility: the greater the silt content, the greater the soil's credibility; the smaller the sand content, the greater the soil's erodibility. Particles in the very fine sand classification behave more like silt than sand. Therefore, the percentage of very fine sand should be subtracted from the total percentage of sand and added to the percentage of silt. Organic Matter The percentage of organic matter was determined, in work by Wischmeier, et al., by the Waikley-Black method (Walkley and Black, 1934). The organic matter content is approximately 1.72 times the percent carbon. Soil erodibility decreases as organic matter content increases. B-2 ------- s-g c: 33 m CO I GO o o a »—« ro o o 33 co o m m 2 UD Metric Tons/Hectare/Metric R Unit First Approximation of K Soil-Erodibility Factor K Metric Tons/Hectare/Metric R Unit o ooooooo o :_ ro w o o o o 8 8 3 S 8 Tons/Acre/English R Unit 'ro CM > oooo ------- Soil Structure The soil structure is descriptive of the overall arrangement of the soil solids. The four parameter values and their descriptions are as follows: Parameter Value Descriptions Granular - All rounded aggregates may be placed in this category. These rounded complexes usually lie loosely and are readily shaken apart. When wetted, the voids are not closed readily by swelling. 1 Very fine granular - less than 1 mm. 2 Fine granular - 1 to 2 mm. 3 Medium granular - 2 to 5 mm. 3 Coarse granular - 5 to 10 mm. 4 Blocky - Aggregates have been reduced to blocks, irregularly six-faced, and with their three dimensions more or less equal. In size, the fragments range from a fraction of an inch to 3 or 4 in. in thickness. 4 Platy - Aggregates are arranged in relatively thin plates or lenses. 4 Prismatic - Aggregates or pillars are vertically oriented, with tops plane, level, and clean cut. They commonly occur in subsoils of arid and semi-arid regions. B-4 ------- Parameter Value Descriptions 4 Columnar - Aggregates or pillars are vertically oriented, with rounded tops. They commonly occur when the soil profile is changing and the horizons are degrading. 4 Massive - Soil units are very large, irregular, featureless as far as characteristic aggregates are concerned. Soil Permeability Soil permeability is the ability of the soil to transmit water. Since different soil horizons vary in permeability, the relative perme- ability classes refer to the soil profile as a whole. The relative permeability classes are as follows: Class Permeability Rates in In/Hour 1 Rapid over 6.0 2 Moderately rapid 2.0 to 6.0 3 Moderate 0.6 to 2.0 4 Moderately slow 0.2 to 0.6 5 Slow 0.06 to 0.2 6 Very slow less than 0.06 Reading the Nomograph Entry values for all of the nomograph curves, except permeability class, are for the upper 6 or 7 in. of soil. For soils in cuts, the entry values are for the upper 6 or 7 in. of the newly exposed layer. In reading the nomograph, interpolate linearly between adjacent curves when the entry data do not coincide with the plotted curves of percent B-5 ------- sand or percent organic matter. The percent of coarse fragments may be significant and is not included in the nomograph. Therefore, reduce the value of K read from the nomograph by 10% for soils with strati- fied subsoils that include layers of small stones or gravel without a seriously impeding layer above them. Enter the left scale of the nomograph with the appropriate percent silt plus very fine sand, move horizontally to intersect the correct percent-sand curve (interpolating to the nearest percent), vertically to the correct organic matter curve, and then horizontally to the right scale for first approximation of soil credibility. For soils having a fine granular structure and moderate perme- ability, the value of K can be obtained directly from this scale. However, if the soil is other than of fine granular structure, or permeability is other than moderate, it is necessary to proceed to the second part of the nomograph, horizontally to intersect the correct structure curve, vertically downward to the permeability curve, and horizontally to the soil erodibility index scale. NOMOGRAPH FOR PREDICTING K VALUES OF HIGH CLAY SUBSOILS Subsoils are commonly heavier in texture than the surface soils, In addition, subsoils likely have aggregating agents that are very much different from those found in surface soils and the degree of aggregation is known to have a profound influence on erodibility. From an EPA study (Roth, et al., 1974) conducted at Purdue University, a multiple linear regression equation and nomograph were developed which can be used to estimate the erodibility factor, K, of many high clay soils. Multiple regression analysis revealed that B-6 ------- amorphous iron, aluminum and silicon hydrous oxides serve as soil stabilizers in subsoils (whereas, organic matter is the major stabilizer in surface soils). The nomograph was developed from the multiple linear regression equation relating the credibility factor to the soil texture factor, M, the amount of CDB (citrate- dithionite-bicarbonate) extractable iron and aluminum oxides, and the amount of CDB extractable silica. The equation used to derive the nomograph was: K . = 0.32114 + 2.0167 x 10"4 M - 0.14440 (% Fe^ + % Al^) - 0.83686 (% Si02) where K d = predicted K value of subsoil M = soil texture factor, defined by percent new silt (percent new silt + percent new sand). "New" silt has 2 to 100 urn mean diameter. "New" sand has 100 to 2,000 ym mean diameter. % Fe,>03 = percent CBD extractable iron oxide of soil. % A1203 = percent CDB extractable aluminum oxide of soil. % Si02 = percent CDB extractable silica in soil. The nomograph for estimating the credibility factor, K, of high clay subsoils is reproduced in Figure B-2. B-7 ------- ? o E 6 '0 3 20 O £ 30 1 40 c/> I 5° L ? 6° > 70 + *• Of) — OU c 90 o> u « inn rerceni \ re2^>^ T AI2U3 ; n • * • • a -BB=. / ^ ^ ^ / / / ^ x __,« — ^ X / x / /> /' •, ^ ^ P«rc (O.I x // /x/ x ^ f f / "^^ * ^ ^ ent — 2 x // X x ^ x' / / , T***!^ ^ ^ *>< Sand mm ) T 0 0.5 2 3 — 4 /; 60 .50 •-^.40 __—- 30 ^ X -20 • 15 NO 0 Percent / '/ '/ ^ X X / '/ / / s jf '/ ' ,' / , / / / J A f * s s /' / / , f ',*' ' 'j f s f s S J / / __/ / . t J • X : x X j '•/ I I I • • • • * * • / // ;/ X 1 / X '/ / / f, f '/ f t s X / / /, '/ r , X X X / ' 1 0.4 1 ,.j 0.3 0.2 0. 1 o 0 0.2 0.4 0.6 0.8 Tons /Acre/English R Unit i i 0 1000 2000 3000 40OO Factor M 0 0.2 0.4 0.6 0.8 1.0 I.I Metric Tons/Hectare/Metric R Unit Soil Erodibility Factor K FIGURE B-2 NOMOGRAPH FOR ESTIMATING THE ERODIBILITY FACTOR K OF HIGH CLAY SUBSOILS (ROTH ET AL,, 1974) B-8 ------- REFERENCES FOR APPENDIX B Roth, C.B., Nelson, D.W., and Romkens, M.J.M., 1974. "Prediction of Subsoil Erodibility Using Chemical, Mineralogical, and Physical Parameters," for the U. S. Environmental Protection Agency (EPA-660/2-74-043), Washington, D.C. Walkley, A., and Black, I.A., 1934. "An Examination of the Degtjareff Method for determining Soil Organic Matter," Soil Sci., 37, pp. 29-38. Wischmeier, W.H., Johnson, C.B., and Cross, B.U., 1971. "A Soil Erodibility Nomograph for Farmland and Construction Sites," J. Soil and Hater Conservation, 26:189-193. "Technical Guide to Erosion and Sediment Control Design (Draft)," 1973. Water Resources Administration, Maryland Department of Natural Resources, Annapolis, Maryland. B-9 ------- ------- APPENDIX C STREAM AND RIVER DATA Table C-l Stream and River Reaeration and Deoxygenatlon Rates (From Hydroscience, 1971) Table C-2 Deoxygenatlon Rate Constants (From Bansal, 1975) Table C-3 Alluvial Channel and Sediment Data (From Schumm, 1960) C-l ------- TABLE C-l STREAM AND RIVER REAERATION AND DEOXYGENATION RATES (FROM HYDROSCIENCE, 1971) River Name Category Grand River Shallow (Michigan) Clinton River Shallow o (Michigan) i Truckee River Shallow (Nevada) Fl int River Shallow (Michigan) Jackson River Shallow (Virginia) N. Branch Shallow Depth (ft. ) 1.9 1.58 1.67 1.67 1.67 2.1 2.6 2.6 1.7 1.9 3 2 Area 2 320.0 44.6 150. 150. 150. 210. 200. 400. 290. 400. 365. 100. Flow (cfs) 295. 33. 180. 195. 271. 134. 174. 174. 204. 204. 100. 100. Velocity (fps) 0.92 0.72 1.20 1 .30 1.81 0.64 0.83 0.44 0.73 0.51 0.27 1.0 k a @20°C (I/day) 4.5 5.9 5.6 5.7 6.6 3.5 3.9 3.1 5.0 2.2 4.1 9.0 k @20°C (1/da.y) 0.59 3.37 0.36 0.36 0.96 0.56 0.63 0.69 0.69 0.69 1 .25 0.40 Potomac River (Md., W.Va.) ------- TABLE C-l (continued) River Name Category Depth ft. Velocity (fps) ka @20 C kL 1320 C (I/day) (I/day) o i oo Clarion River (Penna.) South River Ivel River (England) Shallow Lark River (England) Shallow Shallow 1 1.9 1-2 1 .21 1.51 1.09 1.50 1.08 0.38 1.12 1.46 1.31 2.44 2.03 1.74 1.47 1.82 2.41 1 - 10. 35. 10.07 10.94 10.94 36.20 36.20 0.55 4.86 4.15 3.87 15.40 4.86 4.15 3.87 15.40 15.40 10.07 0.14 0.14 0.13 0.37 0.16 0.15 0.13 0.38 0.47 0.23 0.22 0.28 0.37 0.50 0.43 2.26 35 06 20 37 57 09 18 18 18 0.90 1.66 0.78 2.12 1.41 0.31 ------- TABLE C-l (continued) o River Name Derwent River (England) Black Beck River (England) St. Sunday's Beck (Eng.) Yewdale Beck (England) Category Shallow Shallow Shallow Depth [ft. Elk River (Penna.) Shallow 0.72 0.89 0,85 0.40 0.40 0.39 0.60 0.69 1.00 0.82 0.78 0.64 0.48 0.72 0.66 0.67 0.69 0.9 Flow (cfs) 21 .60 21 .60 21.60 2.70 2.70 2.70 17.70 17.70 17.70 19.10 19.10 5.10 5.10 17.30 17.30 17.30 17.30 Velocity (fps) 1.37 1.19 1.07 0.44 0.56 0.63 1.83 1.81 1.54 1.07 1.27 0.46 0.60 1.16 1.31 1.30 1.25 a @20°C kL @20 C 0.97 (I/day) (I/day) 31 .80 24.53 34.57 25.59 28.34 22.80 49.17 30.77 18.46 21 .05 16.06 12.04 30.32 18.90 20.25 17.09 19.16 5.84 ------- TABLE C-l (continued) o C71 River Name Mohawk River Mohawk River (New York) North Branch Susquehanna New River (Virginia) Wabash (Indiana) Clinch River (T.V.) Holston (T.V.) Category Shallow Medium Medium Medium Medium Medi urn Medium Depth (ft.) Area 9 (ft2) Flow (cfs) Velocity (fps) k a @20 C (I/day) k, L @20°C (I/day 3 15 5-7 3.27 5.09 4.42 6.14 5.65 7.17 11.41 2.12 2.93 4.54 9.50 6.29 143. 3,800. 1,700. 1,720. 800. 1,000. 1,200. .21 0.60 0.70 .07-4.0 1.5 1.04 1,000- 5,000 3,300. 4,500 3,190 5,890 5,910 5,930 10,385 3,230 6,400 14,085 10,440 6,540 3.07 3.69 3.10 2.68 2.78 2.64 2.92 2.47 3.44 4.65 3.94 2.51 2.27 1.44 .98 .50 .74 1 .13 .28 3.36 2.79 1.57 .46 .39 .23 .40 0.35 2.5 0.5 .40 ------- TABLE C-1 (continued) River Name Category Depth !ft. Flow 'cfs' Velocity (fps) ka @20°C @20°C (I/day) (I/day) n Holston River (T.V.) Fr. Broad (T.V.) Medium Medi urn Wautaga River (T.V.) Hiwassee River (T.V.) Medium Medium 7.52 7.07 5.44 8.06 3.98 9.38 10.19 3.29 4.74 5.72 6.98 4.29 6.01 7.16 9.49 3.42 3.02 2.83 10,500 10,500 5,590 11,930 952 12, 17. 44, 8. 12. 17, 4. 8. 12. 010 120 105 775 455 270 150 775 455 17,270 3,112 1 ,145 1,145 3.15 3.30 3.11 4.28 2.73 .41 .06 .40 .46 4.02 52 85 .75 .23 3.71 5.0 3.05 3.91 .27 .55 .54 .60 1.25 1 .27 .23 .88 .84 .88 .91 .00 .55 .98 .25 43. 11 21 5.6 1.7 3.2 Ohio River Deep 32 43,000 6,000 .14 .06 ------- TABLE C-l (continued) River Name Category Flow [cfs' Velocity (fps) kan (?20 C @20°C (I/day) (I/day) o -q Upper Hudson (Troy, N.Y.- Saugerties) Lower Sacramento River Upper James River (Va.) Deep Deep Deep Illinois River Deep 17.5 21.0 15-20 15.5 10-12 9.2 9.0 8.9 6,000 6,750 8,000 11,500 14,500 14,500 14,000 14,500 13,500 15,000 3,000 4,500 10,000 1,800 2,600 9,000 7,500 4,500 3,800 1,350 8,000 0.5 1.5 1.5 0.16 0.18 0.63 0.53 0.31 0.28 0.13 1.37 1.57 1.63 .34 .34 .28 .15 .24 ,15 .14 .12 .13 .22 .24 .22 ,225 .269 ,224 .125 .165 .40 .48 .30 .31 .41 .39 .38 .43 .07 ------- TABLE C-2 DEOXYGENATION RATE CONSTANTS (FROM BANSAL, 1975) X-section Discharge area Top Width cfs sq ft. ft. Kansas River at 15,200 2,160 2,090 2,440 1,300 828 632 1,080 Kansas River at 1,750 1 ,360 2,060 2,300 1 ,040 793 1,170 Kansas River at 3,040 1 ,460 1 ,800 2,690 1 ,900 764 631 608 Bonner Spri 4,300 1,200 1,170 1 ,300 850 550 425 710 Lecompton, 750 590 880 1 ,000 450 350 500 ngs, Kansas 770 505 500 525 450 415 405 432 Kansas 725 660 774 757 592 538 620 kj_ rates base e/day Temp °C 25 28 25 24 9 5 9 14 27 32 28 10 6 0 16 Observed .02 .12 .12 .24 .02 .16 .26 .17 .19 .15 .35 .30 .47 .23 .05 Estimated (From Fig. C-l) .258 .249 .242 .241 .204 .190 .195 .213 .232 .239 .236 .201 .184 .169 .206 Topeka, Kansas 1,450 700 865 1 ,285 910 365 310 290 468 437 447 466 450 405 368 364 22 31 27 18 7 7 11 15 .08 .07 .1 .37 .14 .06 .23 .10 .241 .248 .243 .230 .200 .189 .196 .204 C-8 ------- TABLE C-2 (continued) kj_ rates base e/day Di X-section scharge area Top Width Temp cfs sq ft. ft. °C Republic River below Mil ford, Smoky Hill Smoky Hill Solomon Ri 258 657 609 201 15 36 249 River 215 100 373 146 113 210 157 River 185 67 734 ver at 61 35 117 184 412 392 140 10 26 177 at Enterprise 122 57 211 83 65 120 88 at New Cambri 87 35 252 Niles, Kansas 65 40 125 Kansas 196 251 249 166 68 77 192 , Kansas 119 69 131 91 75 118 97 dge, Kansas 86 79 88 53 49 61 24 28 24 14 1 0 16 27 32 24 6 0 15 14 27 31 29 28 30 21 Observed .18 .19 .07 .25 .14 .23 .29 .09 .26 .16 .32 .14 .17 .24 .09 .19 .27 .21 .19 .06 Estimated (From Fig. C-l) .224 .242 .283 .203 .153 .161 .208 .232 .238 .234 .193 .173 .207 .204 .232 .225 .255 .237 .234 .231 C-9 ------- TABLE C-2 (continued) k|_ rates base e/day X-section Discharge area Top Width cfs sq ft. ft. Temp. °C Observed Estimated (From Fig. C-l) Kansas River at Wamego, Kansas 890 1,540 2,530 1,470 680 535 483 Big Blue River 1 ,060 162 90 810 961 232 50 50 Kansas River at 1 ,250 559 1,200 511 390 670 1,080 730 300 225 190 at Tuttle Creek, 1,050 - 70 42 490 1 ,000 108 30 30 Manhattan (Fort 4,250 1 ,750 4,050 367 413 468 540 462 395 381 375 Kansas 194 76 62 191 194 92 52 52 Riley), 533 493 530 247 27 26 27 15 0 2 7 22 24 27 23 8 1 6 13 Kansas 26 32 26 25 .23 .13 .30 .26 .28 .11 .06 .21 .14 .23 .28 .6 .37 .15 .2 .26 .15 .10 .09 .231 .236 .244 .214 .171 .172 .181 .251 .224 .225 .240 .217 .179 .181 .195 .268 .265 .267 .234 C-10 ------- TABLE C-2 (continued) k|_ rates base e/day Di Solomon Ri scharge cfs ver at 44 47 79 30 48 33 30 X-section area sq ft. Glen Elder 38 40 58 30 41 31 30 Top Width ft. , Kansas 49 49 53 33 49 36 33 Temp. °C 28 28 24 7 0 0 5 Observed .20 .23 .10 .35 .34 .37 .35 Estimated (From Fig. C-l) .229 .23 .227 .21 .172 .173 .185 Saline River at Tescott, Kansas Smoky Hill Smoky Hill 8.3 5.8 132 River 138 35 675 River 77 147 493 249 14 21 18 81 14 10 75 at Mentor, 88 20 288 at Langley 60 85 210 122 15 21 19 60 19.4 17.8 30 Kansas 83 81.5 92.5 , Kansas 57 67 90 75 20 23 22 58 2.7 28 21 24 26 26 23 27 24 23 7 1 6 11 .37 .25 .26 .10 .15 .42 .42 .51 .14 .14 .20 .28 .29 .33 .226 .224 .235 .226 .207 .25 .224 .236 .240 .232 .186 .176 .186 .199 C-ll ------- TABLE C-2 (continued) k[_ rates base e/day Discharge cfs iver, Michi 295 X-section area sq ft. gan 320 Top Width ft. 168.4 Temp. °C 20 Observed .59 Estimated (From Fig. c-D .228 River, Michigan 33 44.6 28.22 20 3.37 .225 River, Nevada 180 195 271 iver, Michi 134 174 174 204 204 150 150 150 gan 210 200 400 296 400 89.8 89.8 89.8 100 76.9 153.8 170.6 210.5 20 20 20 20 20 20 20 .36 .36 .96 .56 .63 .69 .69 .69 .226 .226 .226 .230 .233 .233 .226 .228 Jackson River, Virginia' 100 365 122 20 1.25 ,236 North Branch Potomac River (Maryland, West Virginia) 100 100 50 20 .4 ,229 North Branch Susquehanna 1,000 1,700 425 20 .35 ,241 C-12 ------- TABLE C-2 (continued) k|_ rates base e/day X-section Discharge area cfs sq ft. New River, Virginia 1,200 1,720 Upper Hudson, Troy, New York 3,000 6,000 4,500 6,750 Lower Sacramento River 10,000 8,000 Upper James River, Virginia 1,800 8,000 2,600 11,500 9,000 14,500 7,500 14,000 4,500 14,500 3,800 13,500 1,350 15,000 Cooper River, South Carolina 10,000 40,000 Savannah River, Georgia and 7,000 10,000 6,800 40,000 Top Width ft. 344 343 321 457 742 935.5 935.5 903.2 935.2 871 967.7 1,000 South Carol 1,000 1,428.6 Temp. °C 20 20 20 20 20 20 20 20 20 20 20 20 ina 20 20 Observed .5 .125 .165 .4 .48 .30 .31 .41 .39 .38 .43 .3 .3 .3 Estimated (From Fig. c-D .245 .269 .273 .269 .267 .267 .267 .267 .267 .267 .267 .286 .258 .279 C-13 ------- TABLE C-2 (continued) k^ rates base e/day X-section Estimated Discharge area Top Width Temp. (From Fig. cfs sq. ft. ft. °C Observed C-l )' South New Jersey 23 2,500 208.3 20 .2 .262 Compton Creek, New Jersey 10 1,000 69 20 .23 .265 10 790 75 20 .23 .259 C-14 ------- TABLE C-3 ALLUVIAL CHANNEL AND SEDIMENT DATA (FROM SCHUMM, 1960) Location Willow Creek near Cheyenne Wells, Colo- Smoky Hill River near Arapahoe.Colo--- Smoky Hill River near Sharon Springs, Smoky Hill River at Russell Springs, Smoky Hill River near Arnold, Kans Smoky Hill River near Russell, Kans Smoky Hill River at Dorrence,Kans Smoky Hill River near Kanopolis Smoky Hill River near Bridgeport Smoky Hill River near Junction City, Kansas River near T^ek'a^ans Arlkaree River near Ankaree , Colo Arikaree River at Haigler,Nebr Republican River near Stratton.Nebi South Fork Republican River near Benk- Republican River near Benkleman,Nebr-- Republican River near BostwickfHardy ) , Republican River at Concordia.Kans Republican River at Junction City, Kans South Fork Powder River near Kaycee, Middle Fork Powder River above Kaycee, Middle Fork Powder River near Kaycee, Powder River below Arvada,Wyo Powder River near Locate, Mont Crazy Woman Creek near Arvada.Wyo — Little Powder River at Broadus, Mont- Bighorn River near Kane, Wyo Badwater Creek near Lysite,Wyo Badwater Creek at Lysite.Wyo Cottonwood Creek at Winchester, Wyo-- Gooseberry Creek at Pulliam,Wyo GraybuJl River near Basin, Wyo Bates Creek near Alcova, Wyo --- Med i a n grain size, (mm) 1.10 85 .41 1.30 .80 93 .81 1 30 63 .40 023 1.20 .70 .75 1 10 .25 38 .48 25 52 .63 .70 60 0.63 ?2.0 .40 21 42 .50 4 10 16 43 24 21 1 0 8.0 50 90 Smoky Hill -Kansas Rivers system Weighted Silt- Silt- mean clay in clay in silt-clay bank channel M Width (percent) (percent) (percent) (feet) 72 49 25 21 63 30 76 69 96 85 97 90 93 57 82 65 31 44 23 88 29 34 59 71 60 69 70 58 75 82 35 47 58 69 15 45 72 63 3 16 3 6 1 4 45 2 2.4 3 43 2 24 1 5 3 .5 44 4 14 3 13 87 89 5 6 1 3 8 5 3 Republican River System 3 4.7 3 8 3 3.4 15 34 6 67 5 44 1 2 8 2 1 .4 1 3.4 Powder River System 9 11.3 14 20 15 23 4 65 13 15 2 17 65 22 20 21 3 6.7 5 7 3 2 14 8 84 25 57 7 9 9 14 18 15 65 200 263 226 345 115 130 92 69 125 153 636 800 206 68 400 100 123 115 154 250 300 119 35 47 175 234 33 40 220 50 109 35 133 59 134 69 Depth (feet) 1 7 2 3 2 5 3 0 2 5 2.5 3 5 4.0 5 5 5 0 18 5 0 10 18 2 2 3 0 3.0 2.3 2 5 2 7 5 0 5.0 6 5 2.3 2.5 4 4 3.5 4 5 4 4 5 5 8 5 2.3 2 5 3.9 3.5 2 4 3 1 2 8 Width depth ratio (F) 8 8 28 80 88 90 138 33 33 17 14 7 31 64 44 94 23 133 43 49 43 31 50 46 52 14 11 50 52 7.5 7 3 26 22 44 9.0 38 25 43 25 Gradient (S) 0 003 .00066 .0007 .0005 0004 0008 0005 0 002 002 003 .009 .0008 0007 0007 0.004 .005 0015 .0011 .0037 .0037 .0015 .006 .0015 0035 Mean annual flood (cfs) 5,800 8,000 9,200 6,750 11,500 13,000 39,000 48,000 3,500 4,500 2,175 12,000 13,000 15,000 3,900 574 1,630 9,400 1,150 1,280 16,100 585 311 3,140 500 Mean annual discharge (cfs) 30(est) 65 2 215 314 340 1,254 1,454 4,398 5,155 19.6 56 8 105 843 1,000 35 58 133 639 40 39 2,888 34 10 178 16 Drainage area (sq mi) 5,220 6,965 7,857 8.110 18,830 19,900 55,240 56,710 1,460 2,580 4,770 5.760 22,400 23,540 24,900 1,150 450 980 956 15,900 484 371 1,130 377 C-15 ------- TABLE C-3 (continued) Locati on Sage Creek, S Dak. • \£ I Sand Creek, Nebr- Arroyo Calabasas, N. Mex. • Bayou Gulch , Colo. : Medano Creek, Colo • Paradise Creek near Paradise, Kans North Fork Solomon River near Downs Kans Solomon River at Benmngton(Ni IPS ) ,Kans- raine og Sappa Creek at Reaver City, Nebr y Frenchman Creek at Hamlet, Nebr Blackwood Creek at Culbertson, Nebr Red Willow Creek near Red Willow, Nebr -- South Loup River near Cumro, Nebr Niobrara River near Colclesser ,Nebr White River at Interior, S Dak Median grain size, DSO (mm) 0 06 06 12 12 .73 35 84 .50 75 .58 55 .24 24 .24 3 57 50 80 41 90 60 70 70 1 10 27 02 25 33 15 50 7^ Silt- clay in bank (percent) 93 93 96 70 60 65 18 26 16 13 6 5 .5 5 93 74 89 90 82 97 96 95 95 93 91 91 80 47 86 89 5f, Silt- clay in channel (percent) 55 68 40 14 15 10 3 3 5 4 4 1 1 5 5 7 8 1 2 4 1 5 2 17 2 2 5 8 7 75 30 9 4 2 32 5 2 f, Weighted mean •nit-clay M (percent) 73 79 54 23 22 20 4.1 4 8 5.8 4.4 4 1 1 1 5 11 30 16 11 19 23 43 19 35 31 81 45 16 3.3 56 5 3 3 Width (feet) 16 20 31 75 65 36 79 92 100 130 128 340 800 820 93 32 82 112 45 43 26 40 28 36 27 45 143 224 25 293 221 Depth (feet) 7 7 5 7 7 4 3 4 4 3 1.5 2 3 2 5 3 7.8 8.6 5 6.2 6.0 6 3 4 5 8 0 6 5 8 4 7 1 7 3 3 4 10 0 5 8 5 0 Width depth ratio (F) 2 3 2.9 6 2 10 7 9 3 9.0 26.3 23.0 25.0 43 85 170 267 328 31 4.1 9 6 22 7.2 7.2 4.1 8.9 3 5 5 5 3.2 6 3 19 6 65.9 2 5 50 6 44 2 Gradient (S) 0.0055 0045 .0045 .0015 .003 .001 013 .009 on .010 .016 .017 .019 .016 .001 0006 0005 0013 .003 .001 001 .0013 0021 001 003 003 002 0025 Mean annual flood (cfs) 4,300 1,300 8,000 7,000 2,600 1,800 1,360 1,000 450 850 690 2,220 2,080 880 10,900 3.660 Mean annual discharge (cfs) 88 3 11 1 151 558 33 2 111 39 1 28 8 12 5 101 5 8 43 1 165 20 4 302 113 Drainage area (sq mi) 1 7 3 4 9.5 17.9 22 2 22 5 3 8 24 2 25.8 19 7 22.9 25 8 26.1 28 8 1,602 212 2,390 6,770 721 3,840 1,500 2,060 1 ,460 1 ,480 290 400 1,340 2,000 676 7,143 C-16 ------- APPENDIX D IMPOUNDMENT THERMAL PROFILES Thermal profile plots are provided (on microfiche in enclosed envelope for EPA-published manual; as Part 3, EPA-600/6-82-004c, for paper copies pur- chased from the National Technical Information Service) for a variety of im- poundment sizes and geographic locations throughout the United States. The locations are arranged in alphabetical order. Within each location set, the plots are ordered by depth and hydraulic residence time. An index to the plots is provided below, and the modeling approach is described in Appendix F, Atlanta, Georgia 20-ft Initial Maximum Depth D-4 40-ft Initial Maximum Depth D-14 75-ft Initial Maximum Depth D-24 100-ft Initial Maximum Depth .... D-34 200-ft Initial Maximum Depth .... D-44 Billings, Montana 20-ft Initial Maximum Depth D-54 40-ft Initial Maximum Depth D-64 75-ft Initial Maximum Depth D-74 100-ft Initial Maximum Depth .... D-84 200-ft Initial Maximum Depth .... D-94 Burlington, Vermont 20-ft Initial Maximum Depth D-104 40-ft Initial Maximum Depth D-114 75-ft Initial Maximum Depth D-124 100-ft Initial Maximum Depth . . . .D-134 200-ft Initial Maximum Depth . . . .D-144 Flagstaff, Arizona 20-ft Initial Maximum Depth D-154 40-ft Initial Maximum Depth D-164 75-ft Initial Maximum Depth D-174 100-ft Initial Maximum Depth . . . .D-184 200-ft Initial Maximum Depth . . . .D-194 D-l ------- Fresno, California 20-ft Initial Maximum Depth D-204 40-ft Initial Maximum Depth D-214 75-ft Initial Maximum Depth D-224 100-ft Initial Maximum Depth . . . .D-234 200-ft Initial Maximum Depth . . . .D-244 Minneapolis, Minnesota 20-ft Initial Maximum Depth D-254 40-ft Initial Maximum Depth D-264 75-ft Initial Maximum Depth D-274 100-ft Initial Maximum Depth . . . .D-284 200-ft Initial Maximum Depth . . . .D-294 Salt Lake City, Utah 20-ft Initial Maximum Depth D-304 40-ft Initial Maximum Depth D-314 75-ft Initial Maximum Depth D-324 100-ft Initial Maximum Depth . . . .D-334 200-ft Initial Maximum Depth . . . .D-344 San Antonio, Texas 20-ft Initial Maximum Depth D-354 40-ft Initial Maximum Depth D-364 75-ft Initial Maximum Depth D-374 100-ft Initial Maximum Depth . . . .D-384 200-ft Initial Maximum Depth . . . .D-394 Washington, D.C. 20-ft Initial Maximum Depth D-404 40-ft Initial Maximum Depth D-414 75-ft Initial Maximum Depth D-424 100-ft Initial Maximum Depth . . . .D-434 200-ft Initial Max.imum Depth . . . .D-444 Wichita, Kansas 20-ft Initial Maximum Depth D-454 40-ft Initial Maximum Depth D-464 75-ft Initial Maximum Depth D-474 100-ft Initial Maximum Depth . . . .D-484 200-ft Initial Maximum Depth . . . .D-494 D-2 ------- APPENDIX E MODELING THERMAL STRATIFICATION IN IMPOUNDMENTS Figure E-1 Comparison of Computed and Observed Temperature Profiles in Kezar Lake Figure E-2 Comparison of Computed and Observed Temperature Profiles in El Capitan Reservoir Figure E-3 Log of Eddy Conductivity Versus Log Stability— Hungry Horse Data E-1 ------- IMPOUNDMENT THERMAL PROFILE MODEL: BACKGROUND The model used for computation of impoundment temperature profiles is based on the Lake Ecologic Model originally developed by Chen and Orlob (1975). The model was modified for this application to compute temperature alone. The purpose of the model application was to simulate the effects of mixing, impoundment physical characteristics, hydraulic residence time, and climate on the vertical profiles of temperature. Physical Representation Each configuration simulated was idealized as a number of horizon- tally mixed layers. Natural vertical mixing is computed by the use of dispersion coefficients in the vertical mass transport equation. Values of the dispersion coefficients for different size lakes were estimated from previous studies (Water Resources Engineers, Inc., 1969). Temperature Temperatures were computed as a function of depth according to Equation (E-l). 77 3T _ 1 J ,. n 3Tx 9_ ,OTx + ^ , , _0_ _ T 97 (E- v 9l ' c7 9z ( z°z 9z j " 9z igU + cp U AU cp '9t where T = the local water temperature c = specific heat p = fluid density A = cross-sectional area at the fluid element boundary E-2 ------- t = time z = vertical distance D = the eddy diffusion coefficient in the vertical direction Q = advection across the fluid element boundaries A = cross-sectional area of the surface fluid element o M»A = coefficients describing heat transfer across air-water interface 0 = sum of all external additions of heat to fluid volume of fluid element v = element volume Application/Verification The model has recently been used in a lake aeration study (Lorenzen and Fast, 1976). In that study, the model was applied to Kezar Lake in New Hampshire and El Capitan Reservoir in California to verify that artificial mixing could be adequately simulated. Computed temperature profiles were compared to observed values as shown in Figures E-l and E-2. The model performance was judged to be good for the intended purpose of providing guidance for further study. PREPARATION OF THERMAL PROFILES The thermal profiles in Appendix D of this report were prepared by inputting the selected climatological conditions, inflow rate, impoundment physical conditions, and wind. Of these, only wind warrants special dis- cussion here. The remaining model parameters are discussed in the text of Chapter 5. Wind-Induced Mixing and the Eddy Diffusion Coefficient Figure E-3 is a plot of the eddy conductivity coefficient versus stability. It was used to obtain coefficients for wind mixing for the E-3 ------- 0 TEMPERATURE (°C) 20 0 10 26 JUL. 1968 FIGURE E-1 COMPARISON OF COMPUTED AND OBSERVED TEMPERATURE PROFILES IN KEZAR LAKE E-4 ------- EL CAPITAN 1964 - NO MIXING TEMPERATURE (°C) 10 15 20 10 15 20 1C 15 20 25 \l "H 1 1 i 1 1 i 1 1——-i——y C 0 Q 20 40 60 80 -A 1 \ •Simulated -Prototype I SO DAYS 165 DAYS I8ODAYS EL CAPITAN 1966 - WITH AERATION TEMPERATURE (°C) 10 15 20 10 15 20 10 15 20 10 15 20 25 V7 n I i i i i . . i i i i.i • . v 80 100 6ODAYS I 90 DAYS TODAYS ISODAYS FIGURE E-2 COMPARISON OF COMPUTED AND OBSERVED TEMPERATURE PROFILES IN EL CAPITAN RESERVOIR E-5 ------- 9-3 EDDY CONDUCTIVITY COEFF. D (z,t), m* seer1 x |Q4 CD I Ovl m cy^ CO H r~ o H *• X m m 33 m x—> rn pa M a m s. o co —i -< O '—' c c—> 33 -n o o o z m 33 O co c: »• mo d H i—i 2: >— z: CT^ < h-1 o (-> UD 33 O cn co m UD m -n m o co •-< m m O t) M m 33 co c CO CD r; H m N 3 _ O cn 3 r / 7 D C 0 J m r D O < 5 o" ~" XJ o> Y / 1 D C / > // I ( > / ^ B - / O c o < < ; /'c f - 0 / 'D/ X r i 0> ° > O •C < < ±> D C u , o J > > 0 0 o o ^ ^ x D X ~! •• O-^ y / / ^ C [ [ C &n 0 ^ f X n c U a 3 C fe J / / o c r c n f a x r D C 3 D C a a D D> t> > p / / O /f X 1 o D U -1 I J x o y X n < a c x a •i c > 1% > O ^ x T C > X> L ro > ~* i > t» c 3 C O O o 5 / I> C D C o oc o x D C 3 C -\ c ) (0 (0 a> 3 a. x O ro — a> ~ M 2 > m ^ «3 CD O> O) O1 O) D O «> 01 CD cn c r~ CD O) 01 ------- model runs. The upper envelope represents high wind mixing conditions and the lower envelope represents low wind mixing conditions. Note that the plot in Figure E-3 was developed for this model, and the model was then verified with data from Hungry Horse Reservoir, which is located on the South Fork of the Flathead River in northwestern Montana. Accordingly, the extremes of wind mixing and the effects on impoundment stability are as found for Hungry Horse Reservoir. The coefficients should be applicable elsewhere, however, because the eddy diffusion coefficient is relatively insensitive to climate and location. The significance of the eddy conductivity coefficient and its implications for wind mixing may be understood by examining an equation describing transport within the system. Mixing implies the transfer of materials or properties within a system from points of high concentration to points of low concentration, and vice versa. For a system which is undergoing forced convection, it has been observed that the time rate of transport, F, of a property, S, through the system is proportional (other things being equal) to the rate of change of concentration of this property with distance, z. In equation form, this rule is expressed as: F = - D || (E-2) where D is the coefficient of proportionality. The mixing process as defined by Equation (E-2) is variously called "effective diffusion," "eddy diffusion," or the "diffusion analogy" because it is identical in form to the equation describing the process of molecular diffusion. The difference between the two processes, however, is that for molecular diffusion,D is constant, while for turbulent transfer, D is a function of the dynamic character, or the turbulence level, of the system. In general, D is a temporal and spatial variable, and thus will be E-7 ------- referred to here as-D(z,t); 'Equation (E-2) rewritten for heat flow over the reservoir vertical axis is H = -pcD(z,t) fl (E-3) where H = heat flux, HL'V1 _3 p - density of water, ML c = heat capacity of water, HM D O "I D(z,t) = coefficient of eddy conductivity, L T T = temperature, D z = elevation in the reservoir, L t = time T From Equation (E-3), therefore, it may be seen that the rate of heat flux (H), which describes the rate of energy transfer vertically in an impoundment, is a function of the temperature gradient over J\T depth (g^) and the degree of turbulence (induced by wind and other factors) and is characterized by the eddy diffusion coefficient D(z,t) in the equation. It is this coefficient, D(z,t) which is plotted on the ordinate (stability is on the abscissa) in Figure E-3. Surface Heat Flux The simulation of temperature involves the following steps: 1. The net heat transfer at the air-water interface is evaluated for all surface nodes as a function of the meteorological variables and nodal temperatures. 2. The heat input due to shortwave solar radiation is distributed with depth according to the light trans- missibility characteristics of the water (which are a function of the suspended particulates). E-8 ------- 3. Heat is distributed within the water body by hydro- dynamic transport (advection and dispersion) in the same manner as conservative dissolved constituents. The net rate of heat transfer across the air-water interface is computed according to the following heat budget equation: H = q + q - q -q + q (E-4) Msn Mat ^w He - Mc v ' where H - Net rate of heat transfer (Kcal/m2/sec) q = net shortwave solar radiation across the air-water Msn interface, including losses by absorption and scattering in the atmosphere, and reflection at the water surface (Kcal/m2/sec) q = atmospheric long wave radiation across the air-water at interface (Kcal/m2/sec) q = long wave back radiation from the water surface to the 1w 3 atmosphere (Kcal/m2/sec) q = evaporative heat loss (Kcal/m2/sec) q = convective heat exchange between the water surface and the atmosphere (Kcal/m2/sec) The heat transfer terms for long wave back radiation, evaporative heat loss, and convective heat exchange depend on the water temper- ature in the surface nodes (A values), while the solar radiation and atmospheric long wave radiation (y values) are independent of water temperature. Algorithms for the various terms of Equation E-2 are used for separate computation and then summed as shown in Equation E-l. E-9 ------- NOTE: For a more detailed description of the model, its applicability, and the eddy diffusion coefficient, the reader is referred to a report entitled "Mathematical Models for the Prediction of Thermal Energy Changes in Impoundments." (See the list of references at the end of this Appendix.) E-10 ------- REFERENCES FOR APPENDIX E Chen, C.W., and Orlob, G.T., 1975. Ecologic simulation for aquatic environments in systems analysis and simulation in ecology. Academic Press, N.Y., San Francisco, and London. 111:475-588. Lorenzen, M.W., and Fast, A., 1976. A Guide to Aeration/Circulation Techniques for Lake Management: For U.S. Environmental Protection Agency Corvallis, Oregon. Water Resources Engineers, Inc., 1969. Mathematical Models for the Prediction of Thermal Energy Changes in Impoundments. Water Quality Office, Environmental Protection Agency. E-ll ------- ------- APPENDIX F RESERVOIR SEDIMENT DEPOSITION SURVEYS The material in this appendix consists of a reproduction of a bulletin compiled by F. E. Dendy and W. A. Champion, which provides data on rates of sedimentation in U. S. reservoirs. INTRODUCTION Data from known reliable reservoir sedimentation surveys made in the United States through 1970 are summarized in this bulletin. Additional data from surveys made after 1970 are included for a few reservoirs. This bulletin supersedes USDA Miscellaneous Publication No. 1143, which was published in May, 1969.- All reservoir surveys reported in Miscellaneous Publication No. 1143 have been repeated in this bulletin. In addition, it includes surveys made before 1965, but not previously reported, and new data on reservoirs surveyed or resurveyed since 1965. The reservoirs are located in all of the 48 conterminous United States, except Florida, and in Puerto Rico. In addition to data on storage reservoirs and ponds, some information on debris basins is included. A supplement to this bulletin, from which the data were extracted and summarized, contains detailed information about each of the reservoirs ]_/ Dendy, F.E. and" Champion, "W.A., Compilers. Summary of Reservoir Sediment Deposition Surveys Made in the United States Through 1965. U.S. Department of Agriculture Miscellaneous Publication No. 1143, 64 pp., May, 1969. (Cooperative report with the Sedimentation Committee. Water Resources Council). F-l ------- listed in the summary table. The method used in presenting this infor- mation is given on pages F-2, F-3, F-4 and F-5. The supplement has not been distributed with this bulletin because of its bulk and because the detailed information is not of general interest. Copies are available in the offices of the agencies represented on the Sedimentation Committee of the Water Resources Council. Reprints of data sheets for specific reservoirs may be obtained on request from the Director, USDA Sedimentation Laboratory, U.S. Department of Agriculture, Oxford, Miss. 38655. Requests for information not contained in this bulletin or in the supplement should be directed to the agency supplying the data. The accuracy of the survey data varies greatly. Surveys range from reconnaissance measurements of sediment depth at a few locations to detailed surveys based on closely spaced cross sections or contours. No attempt has been made to classify the surveys according to degree of accuracy. Information in this bulletin and in the supplement should prove useful to engineers and watershed planning specialists in private and public practice who are concerned with problems of reservoir sedimen- tation. Engineers, engineering firms and local government agencies who have data on similar reservoir surveys are invited to make this information available to the Sedimentation Committee, WRC, for inclusion in supplements to this publication. EXPLANATION OF THE SUMMARY TABLE Data in the summary table of this bulletin were obtained from the reservoir sedimentation survey data sheets contained in the supplement. Dashes in columns of the table signify that data were unavailable or that the column is not applicable for the reservoir. Reservoirs are grouped according to the 79 drainage areas into which the United States has been divided as shown in the publication, "River Basin Maps Showing Hydrologic Stations," compiled under the auspices of the Subcommittee on Hydrology, Federal Inter-Agency River Basin F-2 ------- 2/ Committee.— An index map of these drainage areas is shown on page F-78. The drainage areas in which the reservoirs are located are shown as subheadings in the si'mrnary table. The first of the two numbers identi- fying a reservoir indicates the drainage basin in which it is located. The second number denotes the particular reservoir in the drainage area and is based upon the order in which the data were prepared. These numbers are the same as those identifying the corresponding survey data sheets in the supplement. When a survey data sheet is revised or when another sheet is prepared with information for additional surveys, the identification number is modified by the addition of letters beginning with a; for example, 13-2, 13-2a, and 13-2b. Total drainage area includes the reservoir area and the area lying above all upstream dams but generally excludes noncontributing drainage areas lying within the watershed boundary. Where available, the drainage area figure published by the U.S. Geological Survey in Water-Supply Papers is usually used. The net drainage area is the sediment-contrib- uting area and generally excludes the reservoir area and the drainage areas above upstream reservoirs, or other structures which are effective sediment traps. The first date shown usually corresponds to the beginning of storage when sediment deposition began. However, for some reservoirs the first date represents the date of the contour or range survey made after the reservoir had been in operation for some time. For most reservoirs, the storage capacity given is the total storage below the level of the crest of an ungated spillway or the top of gates (less gate-height freeboard, if any) of gated spillways. Where capacity values below the spillway crest elevation are given, footnotes are used to explain. 2J U.S. Inter-Agency Committee on Water Resources, Subcommittee on Hydrology. River Basin Maps Showing Hydrologic Stations. U.S. Dept. Com., Weather Bur., Notes on Hydrol. Activ. Bui. 11, 79 pp., 1961. F-3 ------- The capacity-average annual inflow ratio (C/I ratio) was derived from the reservoir storage capacity and the average annual inflow. Normally the average annual inflow for the entire period of record was used to compute the C/I ratios. This time period may or may not correspond to the period for which sediment accumulation was given. Generally, the C/l ratio was not given if upstream structures con- trolled 25 percent or more of the drainage area. The specific weight of deposited sediment is an average or weighted value for the reservoir, determined generally from samples of deposits. In view of the variations with depth and location within the reservoir, specific weight is generally an approximation for the reservoir. The entry is marked by an asterisk where the specific weight is assumed or is calculated from field data or the size-frequency grading of the deposits. The average annual rate of sediment accumulation (acre-feet and tons per square mile of net drainage area) pertains to sediment deposited in the reservoir below the full pool elevation. Sediment deposited in deltas above full pool level or sediment discharged from the reservoir is not included unless explained by footnote. For reservoirs with more than one survey and where the latest survey indicated an increase in the specific weight of deposited sediment, the annual sediment accumulation rate in tons per square mile was not always computed in the same manner. For some reservoirs, compaction of earlier sediment was considered and in others it was not. All of the deposited sediment was assumed to have been transported into the reservoir by water. The agency supplying data is shown in the last column of the table. This agency either has the basic data available or has access to it through cooperative arrangements. The symbols used in this column apply to the following agencies: F-4 ------- ARS - Agricultural Research Service ODW - Ohio Department . .. , ^. Natural Resources-- BR - Bureau of Reclamation Division of Water CE - Corps of Engineers $cs _ So1] Conservation FS - Forest Service Service GS - Geological Survey TVA - Tennessee Valley T.,^ T-II- • r-,. x .14- Authority IMS - Illinois State Water J Survey FORM FOR REPORTING RESERVOIR SEDIMENTATION A completed sample of the reservoir sedimentation data sheet from the supplement is shown on pages F-79 and F-80. This sheet is a convenient and standard form for reporting results of reservoir surveys. An invitation is extended to readers, particularly those practicing engineering individually, in engineering firms, or in local government agencies, to prepare sheets covering surveys known to them but not included in this publication. A blank "Reservoir Sedimentation Data" sheet is enclosed as a tear sheet on pages F-81 and F-82. Additional data sheets may be obtained from the department offices listed on the title page or the form may be reproduced if desired. The completed forms may be sent to any one of the agencies represented on the Sedi- mentation Committee for inclusion in supplements to this bulletin. F-5 ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS HADE IN THE UNITED STATES THROUGH 1970 os DATA SHEET NUMBER 2-1 2-2 2-1 2-1. 2-5 2-6 2-7 3-2 1-3 4-la ,.-2. 4-3 4-4 4-5 4-6 4-7a 4-8a STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL | NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG ANN INFLOW (ACRE-FT PEB SPECIFIC (EIGHT (DRY) LB. PER CU. FT.) AVG. ANN SEDIMENT ACCUMULATION PERSQ MI. OFNETDH AREA FOR PERIOD SHOWN AC.-FT TONS AGENCY SUPPLYING DATA JT. JUH» »CHI*T, PENOBSCOT, SKWEBKC, ANDROSCROOCDI, AND PREciUMPSCOT RIVES BAilN HounLAin 3tre*t Plant* Pond SnuthllU(ton ReMrvolr do 4Mt field • Schoharie (Cllbaa Ehutj do fio t» do do !±-St!L Crirfin *Ur£rt" do d° Wllllxw- Dricffo do • do do ^__?1o— - - Broad Brook River Trib. of Bo»vor Brook Kightsil* Run Budd River *, do Hoose Mountain Branch *'**. n rB 0 > i; pping junpo «r , a v«r 0 do Griffin Greek (Legget,} ing - rrl " J° °*~1" "F "* ff i-ri Msart B k ^ ror rwa o roo do- — do ucan jTncK 3 — 1C .•"!„,,,.,, "• n«ir«Bt, *. 13.9 HOUSA-TUt*!", CONHtCTICUT, THAJCS, -I Broad Brook, xxw, 5.13 Greenfield, Haas. Plaflt8-/6G,410 59,864 1,991 1,953 3,746 3,686 2,686 2,232 i,on 1,0,6 3V6.19 "05.32 617. !16 56.04 <5.9C 55. M. 1P7."1 L87.13 186.70 2V..11 .oa — - - .005 .002 .025 .01') .017 .130 .129 .128 .250 .250 .^49 •50 •50 •50 57.3 *6C bi.,2 .01 .10 .04 .012 .094 609.8 10.9 108.9 43.6 13.07 102.4 •Su I/.156 1/217 •00 ."2 2o.lt. 'V, 2/.20 217.8 .01 4/.618 4/808 .187 23' .699 913 .'"I '47 .237 .034 — .394 421 .022 . )51 459 .r>7 Jii scs scs SC3 SCS ------- 4-11 4-12 4-13 4-U 4-15 4-16 4-17 4-18 fc-19 4-20 5-3 a 5-3 5-6 5-7b s-e 5-9 5-10 5-11 5-12 5-13 6-1 6-2 6-3 6-4 \f Tic 2/ Inc 3/ Par 4/ Net This area y Rev tl Con O/ B" Old :ia.TJfelter Palinjfton Reserv«ir ' ^c ' Ice-aal* " 111 -oatsviile- Lloerty leservcir do Llttl*oDeer %°' !tount Morr-ia do Patterson Greek flfl- Latce Barcroft do— m do do J° btamiton do Jackson . Triadelphia L. (Brighton D.)- do do Cordon Lake Thomas W. Koon Lake Savage River Dam Rocky Gorge- do — South River, Site 26 Lak ao Lake Ap?x do do High Point do iudes 103 acre-feet of sediment d tial survey eoverir.c sequent s 1-1 sediment contributing area wa« 2 was used in the 194J calculations pervasion or sediment pool only. *. 3r. :oioms >e«k— >o»der ;r«e* % ~ , . Jo _ Patapaco do __ Genesee River do Pattern :rwk Trib. of Potomac Ri *'er do Pedlar River ao- 0 ?~ " Ivor . do Patuxerit Siver rt°~ Zvitta Creek Patuxent River do Inch Brancn do Swift Creak do Sallie Keaney GreeK dc Deep River 0 redged in 1937-1939. 4 in Stoney brook Arm Only. 99.4 iq. ui. antl_ 1933 wher Pre Spring Grove, Pa.. — — do do- Joatsville, Pa. do rfards Shaped , Hd. Mount t>rri3, N. Y.— Endwsll, '<. Y. POTOMAC, H^P rails Church, ^a. do Oronooo, Va. Silver Spring, Hd.- Jo Greenbelt, Hd. do St t V aon on, a. do- Kanassas, Va. Brighton, Hd. Cuj^erland, Md. do 31oomington, Md. Laurel, HI. • «ayne9boro, Va. CHOhAN, ROANOhE, TAR, do Franklinton, N. C. jreensboro, S. C. High Point, N. C. ttyboy Dam was couple ted. »M,v of J,l«) ,cr,-f-e. 74.3 2.91 60.7 5.0 164 .74 1,07? 4.3 1.C4 2.90 - 159.1 1,011 4.3 1.64 PAriAt-.O^K, YORK, AND J 14.5 14.3 )3.21 27.0 10/.82 25 337 81.4 64 60 105.0 2.7 l.SR 33.07 26.97 .79 25 336.4 80. 0 59.6 104.44 50.14 2.7 1.85 f-TUSE, Ai'.T GAPE F-.A- R 4.0 4.- 1.13 1.12 74.1 62.8 10/ ?/ i2'' 73.4 62.3 Revised tievlged Koon "..a* 3a3ed on Apr. 1939 1937 Apr. 1939 — 1925 Oct. 1951 July 1951 — 1916 July 1951 Julj 1954 Jan. 1962 June 1958 t.ov. 1%2 Soy. 1951 H»J 1957 May 1963 Oct. 1968 Oct. 1970 Oct. 1908 Oct. 1970 AMES RIVEH oAJLN Jan. 1915 Feb. 1938 Aug. 1957 Feb. 1907 Feb. 1938 Mny 1930 Hw. 1938 July 1936 reb. 1938 Aug. 19^7 June 1968 Dec. 1925 Jan. 19i.O June 1957 July 1930 Aug. 1937 Jan. 1942 Oct. 1950 Sept. 1958 Aug. 1964 3.pt. 1913 Apr. 1940 Har. 1932 Apr. 194 Kar. 1952 thr. 1956 Mar. 1954 Aug. 1964 May 1956 Nov. 1970 Sept. 1966 Aug. 1968 Aug. 1969 1325 June 1941 Jan. 1925 Aug. 1934 Jan. 1928 Aug. 1934 Apr, 19j8 19c8. due to -_vable c total sediment 5' 1.6 20 51 35 -.9 4.4 5.5 5.9 2 2 19.5 31 7.8 1.6 19.5 10.8 .4 17.5 7.2 8.3 7.9 5.9 8.1 4.3 10.4 14.5 1.9 1.0 16 11.5 6.5 3.7 bull in bo 59.9 — a, ooc 27,426 -37 1,019 — 970 138,762.4 1.133 133,227.0 1.129 0/23.3" -- £/!<,. IS -- 336,611 .345 335,393 .344 891.43 .229 887.95 .228 272 . 18 ) 271.38 .182 3/1,847 .142 8/1,762 .134 2/2,092 .161 1,860 — 1,723 - 181 — 95 196 -.312 186 *.296 151 *.2»0 U/147 -234 385 — 373 350 4,500 4,158 12/20,222 .327 20,089 .324 *9,633 .317 19,045 .338 3,129 — 7,312 — 7,294 — 20, -00 .172 20,020 .169 21,390 — 20,789 — 610.4 .28 607.0 .28 196.9- .140 170.99 .122 103.72 .117 1'jb 34.7 — 2,870 2,610 4,354 4,135 — 5 4,033 ed in early sp-ing 1968. '3.2 »60 *50 77 *30 •60 «60 •50 •50 61.1 67 "60 »60 »60 =0.6 .669 .37 .03 .28 .426 6/1.055 1 .25 .20 0/.19 6, .257 .723 .134 .408 7.91 *. 2.27 2 1.52 1 .034 .053 .141 .20 .72 1.2' i .036 .643 1.15 1 .087 15/7. 3916/U 3.93 5 .19 .509 .308 .541 .416 — 433 434 3} 305 ,378. 419 335 ,'r,96 336 533 ,337 ,970 ,°45 181, 213 784 ,€63 840 ,678 110 ',133 402 596 458 ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MAUE [N THE UNITED STATES THROUGH 1970 00 ... DATA SHEET NUMBER RESERVOIR STREAM 1 i ! NEAREST TOWN DRAINAGE AREA (SQUARE MILES) , TOTAL j NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) t CAPACITY AVG ANN INFLOW RATIO (ACRE-KT PER ACHt-KIl SPECIFIC WEIGHT (DRY) LB. PER CU. FT ) AVG ANN SEDIMENT ACCUMULATION PER SO MI. OF NET DH AREA FOB PERIOD SHOWN AGENCY SUPPLYING DATA AC.-FT.I TONS (-5 6-6 6-7 6-S 6-9 6-lOa. 6-11 fc-12 7-7 7-4 T-5 7.6 7-7 7-10 7-11 "-1"- --16 ^ _. "ic— Roxboro City Uk« Burlington Municipal do John H. K«rr- Phil pott do— - Apptlaahl* * Albeaarl* 1-y -Ak«- - do- — Entwhistl* No. 3; Hlgfi Rock L*.ka L«« P«« DM Mfg. 3o. do Norwood L. (""illflry^ J0 3 ° * , 3»tt«rfUld Cr««k 3w»4=«* do Roanok* Rlirsr— do 3«ith Rlvtr sindy T\irk«y Quarter ^r««K South P»col«t Rivap South Tyg«r Hirer , r . ong Hi'chcock Oraek Little River Yadkin Biver „ rw.lt c i as n Hitchcock Jr««k- do S«1M ;r«k °ee De« River ^ _ -to HOWA-V, BOANOKS, TAJi, KEU3E Durhas, N. 7. — . • — koxboro, N C.-- Burllrigton, H. -.- South Kill, 7*. BtMtt, V-. PSE BEE. SAHTffi, . ' L*nc*st*r, 3. C. Flng.nrtll., o. :. do Gr~r, 5. C. Lumapoll*, N. C.. - do_ - do ~5b.M«ll, H. C Troy, N. :. Salisbury, S. -. Rocklngham, H. 0. do Wlr.ston-ialen, N. 0.-- Ht jllead, N. 0. __ -io - State .vills, N. 0. AMI CAFE 107.5 3.75 30.6 7.62 397 7,800 212 AWJ roisrc 16.05 9.40 91.33 63.0 33. C 18.0 4.7 168.") ^69 3,930 50. SO 176 27.63 4,600 6.75 U,*li FUVfi SIV-a BJO 166.7 3.73 30.3 7,52 105.0 397 7,391 185.7 5IVER BiSISS 15.92 9.34 90.6 62.8 n.7 4. 54 yil.o 269 3,863 50.34 V25 27.26 6/431 0.66 4.74 INS (0. pr. Ul. «>. tn« pr. pr. HOT. S.pt. Apr. July DM. D«. Hov. HOT. Oct. FA. J\in« "«J July Kir. Oct. Oct. July *i«. July Jun. Har. )far. Mar. NOT. Aug. Apr. June «a'. Nov. S.pt. July *u«. Apr. *y Sept. Mar. Har «pr OKTIHU 1926 1935 1927 1941 1932 1935 1924 1941 1940 1928 1938 1949 1924 1932 1952 1959 1951 1960 1926 1937 1925 1938 1926 1934 1=>47 1*5 1965 1904 1934 1924 1939 1939 1941 1925 1935 1892 1940 1915 1940 1927 1935 1927 1938 1874 1940 1"19 1939 1928 1940 1935 1940 1951 19'7 1962 1965 .969 EC) 8.75 14.33 2.9 17.2 10.0 11.3 2/9 7.4 8.9 11 13.4 8.2 12.7 18.6 30 15.5 1.9 1 L . ? «a.o 25.0 7.8 11.1 66 19.8 11.75 1.6 11.1 J. 12,671 12,276 103 95 1,115 1,851 531.2 460.3 448.4 1J25 1,202 974 209 2,808,400 2,750,349 201,500 198,000 682 585 190 1/3,506 .2/21891 1/2,593 4/3,109 2,500 1,600 1,070 918 2,600 2,574 1,201 1,122 184 163 1,104 976 289,432 '821 652 464 404 3,099 2,860 136,823 133,300 462 441 419 961.4 948. 5 9<.5 9 °L\I - — — - ~ — 63 .002 — .001 *43 .494 — .484 32.6 .966 — .949 46.2 — 65.3 - - _ — — 61.8 _ — 45.5 *4S5 .186 .184 7/62.2 .183 2/62-2 0.271 .150 .728 .545 1/.342 .155 .104 .2U 1.06 3.06 .55 .417 J/.412 J/.174 .48 .302 .774 1.71 .024 .019 .462 .302 .036 .696 .692 .299 .61 .18 .14 _ — - 213 143 2OO 754 2,103 593 406 - 367 685 296 826 244 1* SCS SOS scs scs scs 3. 3 SCS scs scs scs scs scs scs scs scs scs 305 so: scs scs scs scs ------- 3AVAIUUH, XXKXSS.. UK ALTAMAUA RIVER BASIUS Uh. I«WW Lloyd 3ho»lB North Pork Bn>*4 No. 6 «iorth ^ork Broad >te. ll tiorth fork Broaa So. 1 Horth Pork Broad No. U ^ Omit.. *,.r do Bear Craak- — — — To»'e Creek . do *ortto Fork Broad River 1-1 -J"* do Jac Ml, Bas Toe —do kson, Oa. ., 0. tonolle*, da. do «». G»- —do __ do 1,414 -yo 3.62 3.79 5.75 1.2 — 2A3.86 1,407 3.50 3.67 3.70 1.191 Apr. De*. J.IT Julv JVM Oct. Mar. Apr. 1941 1910 1956 1970 1956 1958 1954 1962 1964 1969 2.9 24-3 10.8 7.4 4.5 1,748 112,538 98,578 12/780. 9 751.55 1Q/792.4 763.9 633.2 281.1 276.« 267.0 - .176 .199 .193 .186 .148 .146 ~ 49.82 •60 55.1 74.8 73.8 63.2 ii/68.6 12/66.2 2.22 .335 .50 .34 ,2O5 .49 .93 2.410 1,140 532 676 4O2 1,645 814 2,234 547 362 1,341 SCS SCS 3CS 3CS 3C3 3A7LUJI, ST XAKrs, ST. JOHH3. UTO SUWUOK! RIVK BASIIO 30UTHIW FLOtltu UUHUJt APAUlCHICOLi AM) OCHLOCKOHB R1VS BASDtf U-l 11-2 11-3 12-1 12-2 U-3 12-i. 12-5 12-4 12-7 12-fl 13-1 13--1* IV ••w*- - •-. -ii -do White Hanganeae Ho. 6 Lake Auburn T ^ Lak* Pyrdy do High Pln« 3u Mo. 5 Barvlew- ._.--- Lake Karri* do * " U> , ** * nd JL° Trlb. of Chickamiaga Cr*ek do __ Pattlt Craek Towi Creak (*rlb. of) Coo RlT Looaa^tti Llttl. cahrti tl«r .^tir»^o^i:m Trlb. of Htgh Plna Village r>«ek - Tello* Crwk do Hn I ^ ogue UM ^*^ *i i f CHOCTAHUTCHKE, reLLOW, Cart«r«Tille. Qa. Auburn, Ala. Clanton, Ala. K^^f^, AU. 11 r iz£r^———~- Sowwkfl, Ala. • TUiCI^SKS, PAS-JiOCAJL Blnaingham, Ala TuacaloOM, Ala. d° * ° g*do**' *' 2.34 J.9 E3CA«1A, 1.60 12.46 1.6 9,087 41.74 7.45 .63 1.8 A, Affi) 0Fi 72.3 30.0 .13 2.31 2.8 AMD ALABAMA 1.51 12/U.o 1.6 9,076.5 40.22 7.18 .61 1.55 RL Rival BA3] 71.6 29.8 - .13 »o». 1937 F*. 1945 JUM 1925 Ikl 1956 IOT! 1970 RJVKR BASICS Julj 1929 JulJ 1939 Oct. 1929 •o.. 1938 T*>. 1931 Jan. 1937 D~. 1913 »aj 1936 Sapt. 1910 tor. 1935 Oct. 1948 "W 1957 Jug. 19S4 *7 1957 *r. 1961 Ka/ 1970 LHS *y 1911 0~. 1935 f*. 1929 •or. 1935 Aug. 1953 Aug. 1949 War 1963 13.4 7.3 31 10.9 10.0 9.2 6.3 22.3 25.2 8.5 3 9.17 24.6 6.75 17.75 13.5 354 218.4 176.6 535.2 •90 865 1,021 900 102 95 156,525 138,520 19,0*3 18,594 1,448.0 1,325.4 65.5 60.5 389.7 385.3 11,866 9,514 2,421 2,373 15/2,636 7.631 6.963 .116 .095 .014 .012 .U2 .167 .090 ».163 «.161 .061 .059 .066 .044 .040 '50 67 75.8 63.7 42.5 44.2 14/53.99 59.9 1.45 .41 3.92 1.66 1.20 .66 .089 .479 2.0 2.74 .32 1.34 .239 .110 .377 1.5*0 846 6,472 1,"40 2,63» 376.3 144 SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SC3 SCS LOWER HISSI53IPPI HI/KB BA3IM (MATGHEZ TO THE fCU^H) C&loiaivu, Htrawitau, and V*r»illon filv«r Baaina ExdudiiV? 2.04 acr«-f**t or ssdiaw •'si-'n f"T58" repo O. Els>att->n o' dam •*• \ cv or ' l«T,t tlsert "—* -"5.0 to I''" - feet anl o-I^lnal ~a »c ty a" e'f J*t.— """' fro« lak» in March 194 ; s«« H. D, 65, 75th ^o Sept. 1956. Dat. bas.n iy In 1940 In 19..9 VO/ Changed on ba»i» of 1970 sur-fey. Lj./ Average of 9 aaMplea. lg/ Average of 1C sajaplaa. lj/ Drainage aroa above reeervolr "o. 3 excluded. 14/ Weighted average Subaergwl sedljwnt 51.75 pcf ' ' ' With s-foot flashboaHs Added In IQf* Eatlaatod or aseuaad. ------- SUMMARY OF KESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM ! ! NEAREST TOWN ! DRAINAGE AREA j (SQUARE | TOTAL MILES) DATE OF PERIOD STORAGE BETWEEN CAPACITY SURVEY SURVEYS (ACRE -FT.) i (YFARS) NET CAPACITY AVG ANN INFLOW UCRE-FT SPECIFIC »EIGHT (DRY) LB PER :u FT ) AVG ANN SEDIMENT ACCUMULATION PER S<3 MI. OF NET DR AGENCY SUPPLYING DATA PERIOD SHOWN ' I AC -FT ! TONS i (CSSISSIPP1 RIVER BA3IN5 (HELENA TO 15-2 15-3 15-4 1 5 15-6 15 7 15—8 15-10 1S-U 15-12 15-13 15-15 15-16 15-17 15 1 15-19 15-20 15 --2 15-23 15-24 l<-2< 15-26b 15-27a ls-28a Lake Wijiona 0. P. White Pond B. H. Honnescuker Pond * H PtinH C. -. Hurdle Pond Agnes Jon«s Pond h L«e Johnaon Pond H~A1 r. T. HcAicxandcr 2° j *t"COKa H Like oooLniid Fletcher Hurdle Pond (North ;- h ( So li 1 do Gayooo Lake Ben 0. Pettis Pond do R. X. Williams ifenry W. Ramsey Pond do Dr. Braalett Pond do • ' lrl0 Pond Ben P. Smith Pond do A. L. Rodman Pond Charles Dockery Po'-d do V.. ¥. Murphy Pond do do j Alu,-n Fork Saline River Trib. of Chewalia Creek Trib. of Coldwater Siver-- H ""rib. of Coldwater liver— ,°^ 'r * ' * Ur "" ' C Ri no o oiauato i r T r " 0 Trib. of Red Banks Creek— Trib. of Byhalia Creek 0 do Tric.^of Coffa-a Creek— Trib. of "ississippi River Trib. of Toby Tubby Creek- do- ^ "Yib, of Sartor Cr-ee* do .rid. o. aiiarat^nle Trib. o" Pigeon Roost ~r - Trib. of Kurncare Creek— do Trib. of Jones Creek do East Goose Creek P g > ."* Little Rock, Ark. 43.0 Holly Springs, Hiss.— .OO97 Slayden, Hiss. .0625 0 ^^ H " Holly Springs, Kiss.— .0473 H° <~,"\ do . } o . yj4 Warsaw, MISS. .1019 Victoria, Miss. .0406 do riolJy Springs, Mna.— .0342 Horn Lake, Mi-is. .2196 Oxford, Kiss. .OO75 ao do . 4iU Taylor, Kiss. .02'>9 Cxloru, MibS. .1375 do ates i^.e, _ss. .0456 Holly Springs, Miss.— .0278 Arkabutla, Mi-53. .1563 Eudora, Miss. .0644 Arkabutla, Miss. 1,000 do __ '•oily Springs, Mlsa.-- .206 do ..^ord, Mi-is. ,^P6 j ' a ^ .0069 .0597 • J^ .0^51 • ' " •4'' .0954 ,011k .0389 __ .0320 .20J.7 .'K6? . 413 .1289 ._'" .0398 .0264 .14^8 .0566 943 .200 ".4-7 Cc-,. May Oct. Jan. in i c- Oct. I111" * UK. "" Feb! Feb. Feb. Feb. Feb. Aug. Feb. Feb. u ^ar. Sept. Xar. Jan. Mar. Mar. July Sept. Mar. Apr. toy Mov. Sept. Nov. Apr. c ' 1937 1950 19*7 iq^A 1QM 1940 iqjj* IQ^l 1942 1951 191b 1951 1947 1951 1948 1951 1942 1916 1951 1946 1951 1933 1951 1951 1951 1947 1951 1945 1946 1951 1939 1962 1953 1959 1963 1953 in a 12.6 4.0 i f ' J i -7 j. f. 35.0 4. - 4.0 2.7 - - 35.0 1-; u IS. 2 14.2 "> - r T — n»I»2 " '.3 '~'i 521, :i i, I, 12! p 36, 29. 8, 6, 2, 1, 2?6 94 ^8, If, 12. 12, q. 4. 2. 5. 3. 6. 4. 53. 1. 9. fc. 4. 2 31. 24, lu 17. 16. 3. 3. 30. 29. 23. 22. ,300 540 060 /2P. 19. 17. /J" ' ^s! ?i. 19. :: .46 — .07 ,0 — .35 — .1* — ,0 .80 .40 .8 , i,h ,11 __ — .1 — .9 ,1 .3 .66 — ,61 ,67 ,48 ,cl .47 — ,23 ,0 ,63 — ,07 ,93 .70 ,43 r4 ,C ,9 ,4 ,6 ,77 29 5 — 0 — C 0 .499 .495 -4S7 -jg 5.194 1? >.169 84 «.152 77 *.l,-5 Po 3^ 40 "SO *50 — 63, — 60, — o~, o7, 7b. 84, bl, — 39. — 66. 63, — 63. — 83. — 78. .6? .09 .9 .27 .13 .24 .05 .9 ,fi ,3 ,0 ,1 ,e 51-85 — '6, — 55. — 47. — 41. *37 — 52. — 67. — r50 — *44 — **>G *60 -*90 *90 *90 66 70 70 «70 ,72 72 .7.. • 75 ,04 58 0 — 13 — I1; — 7 12. 16 .11 .37 .1 18 .3 20 .78 10 .4 18 .6 27 12.4 ?2 "^ — 5. -_ i, — •j, 12, — . 16, — .Oj 10 . '2 4 .*P 6 .55 9 .5 17 .8 30 26.0 44 1.13 i — 2, .._ 3. — r,1 — 2. 1. — 3. — 4. — 1. — 3, 2/8. "3/3 2/3. 2A 2/5! 2/5. 2/1. .19 j T, i. 5 21 ,61 2 .12 .14 3 ,3° 7 .95 2 60 3 ,627 620 .4 t/16 5 "a/-" 5 i/6 66 2/8 87 2/8 30 2/8 38 2/2 120 403 — ,200 — ',000 — ,700 ,200 ,500 ,?00 ,»OC — ,800 — ,520 ,040 ,100 — ,400 — ,600 ,530 — ,060 — ,0"0 — i3"r — ,37C 913 -- ,'60 — ,200 — ,120 — ,420 — 819 810 ,465. ,448. ,860. ,136. ,949. ,080. ,103. ^ e 7 ± 4 4 o ------- 15-31 15-32 16-1 16- 2 16-3 16-4 16-5 i6-6 16-7 16-9 16-10 16-11 16-12 16-15 16-16 16-17 16-18 16-19 16-20 16-21 16-22. 16-23 1 ac Enid Reeervclr — ^° " en&cU r oer o r- ° -loan ° in fl -a » _ .. rl Loch H.ry " 1 Dering -o*l Co. Pond „ rnrtfl Horodo W»at Fr»nkfort • rfn ?° , ^ er, Plnevlew (Middle) f illarnay — — 0 ' L*k d °~ Crab Orchard L*K« LUt-le Graa»y Like Herrln Reservoir No. 1 .•)*dia»n'_ .ir conservation pool inly. Original i**rfiiB«nr -ang" surveys. Used *i ra^'rininff ,Ute of sediment da do Xooona River lal b eh* Si " -*rc „ .^o ings ~I*««K Browi Creek r t Trib. of Wolf Creek ° ° „ , ut o o r««* (i ° 0 Big Creek q ° " H^°C 3 aP~ F rtf " ° rt " elf Limb B run , Little Grassy Unnamed . _, fX) S 1 *- 3 . ^° 0 *' Enid, Miss. 3 LC«ER KISSIS5IPFI n St. Fran "!*r , a°~ a- *rto^' Kwlington, Ky. T*m ° i m Eldorado, 111. W*«t Frankfort, Ul.- 0 amington , rf 0 Q 0 Annapoln, Mo. fcpi.r fliorr, MO. c «Tion, il. 0 rf r -^ ° iarbondal.. 111. 1«rrin, 111. —lo 11 d t J 1,545 1,454 foO 516 IVEP. BASIN (3HE5TEB IX, Hn ,cio fiiv.r Basin 1.90 1.87 3.99 3.96 3.81 3.65 3.00 2.77 .219 .206 2.23 1.87 4.03 3.75 .63 .07 .56 .06 .49 .48 51 51 1,310 1,206 4.65 4.43 .339 .316 .26 .25 171 160 0.5 ^.31 15.7 14.2 1 . ^8 1 . 70 .33 .32 1.24 1.22 .925 .858 M«T 1956 2.5 S.pi.. 1959 3.3 Hov. 1963 4.1 lar. 1937 — 1 tfaj 1960 20.6 1 1940 — — 19513/ — Xfj 1961 9.83 1942 — 1 July 1953V ~ Hsj 1965 11.13 1 »Ai Oct. 1930 — July 1939 8.8 July 1939 1^ July 1939 10 — 1888 — Dec. 1908 20 3»pt. 1948 22.1 — 1919 — Oct. 1949 30 Oct. 1949 29 S«pt. 1936 10.1 July 1949 12.8 1939 7 1«9 9 193B7y 10 1910 — 1939 » July 19408/ — July 1947 7.0 Mar. 1964 16.7 P«b. 1944 June I960 16.3 1919 -- 1951 32 — 1937 — dug. 1951 14 MJJT 1940 — July 1951 11.2 1921 July 1951 30 Mar. 1942 — July 1951 9.3 1913 — — 1951 38 Dec. 1925 — »ug. l»5l 25.7 *.ug. 1954 14 1925 — — .ulj 1960 35 6/ Net sediment volume in 1949 was 120. 5 2/' CAJH failed spring 1938, surrey conduct 3/ ^riginal data fron topographic survey 5/ Based on tncoDrlett rMurvey; 1963 ™] * Estimatea or assumed. 18.83 17 .T) 16.47 ,569,900 ,549,336 060,030 657,201 , '37.400 ,320,020 24.05 19.56 87.7 82.9 171 158 1,228 1,184 1,386 1,193 89.3 73.0 844.4 726.0 i/lf6*-1- 1,515.0 1,487.8 8.9 8.2 30.9 29.1 8.2 5.4 818 622 625,000 624,651 613,161 1,746 1,659 58.1 46.8 24.0 21.7 67,320 63,894 705 590 25,741 25,365 19" 178 74. b 64.7 150 138 383.94 353.59 ac.-ft. du -,ed July 24 of 1935-36 lue of 0.57 '.102 •.096 •.089 .934 .922 1.073 1.068 .969 .957 •.0^7 •.063 - — - •.025 •.016 .540 .539 .530 .613 .582 .265 .214 .143 .129 .611 .580 .168 .141 2.543 2.506 .173 .155 .350 .304 .201 .184 .598 .551 e to compaction , 1939. is nK>re reliabl •90 2/6.2 2/12,153.2 •90 2/2.07 2/4,^57.6 •90 2/1.87 2/3,665.6 •60 •60 •40 7S4 54.8 64 •60 73. V •76 •67 •60 •60 •65 •60 34.0 56.6 36.8 47.5 34.5 38.7 27.5 62.9 44.5 37.1 o1" earlii e. .667 .558 1.205 1.133 .a3 .33? .600 3.15 2.64 2.18 6/933 1.43 3.3 .583 .133 2/.0414 .5705 1.20 .64 1.91 .61 2.85 .32 1.22 896 729 1 ,575 1,860 254 1.71 784 ',,070 4,370 3,180 1,870 4,310 825 174 888 1,368 1,976 1.58 2,402 192 1,671 .69 692 1.01 816.1 er deposits. Ci CE 6CS SOS MS IWS IW 505 SCS IWS MB Mi MS IWS rws MS I.'S MS ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IK THE UNITED STATES THROUGH 1970 SHEET NUMBER RESERVOIR 1 1 | STREAM NEAREST TO»N ; DRAINAGE AREA I | (SQUARE MILES) | TOTAL | NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG ANN RATIO (ACHE-rr PER SPECIFIC (EIGHT [DRY) IB. PER CU FT.) AVG. ANN SEDMENT ACCUMULATION PER SO MI. OF NET OR AREA FOR PERIOD SHOW AC -FT. | TONS AGENCY SUPPLYING DATA i HISSicSlPPI RIVVi BASIS (CHE3T«B TO HKLBU) St. prancis River 3*«ln (Conttnuad) IS-36. \^-n lfe-2s 16-31 16-32 U-J1 16-3e 17-1 17-2a 17-3 17-j. l"-ft 17-7 I"1-"* 17 9 17-10 17-13 17-lU 17-U* n-1- "'-IS "W £~T^»«.rtU.- Uk* .ohnton :ity — -«o - Heat rrankfort (Sewi ~ '" ' • 1 -to — Hough River rtS Ho. 1 Oblon Creoh PRS 124 Had Hlver FRS Ho. 14 ~^ LUX- flT .«ii*J .t»«k Mr j f u " - ^~ " Kuntlnifburg (Uoper) Oakland "ity if? • n1O Chafer Uto- 5pr;r,a Mill 10 Yerallion Lake Brown Park Lace 'rfc1^ avUaon 3 c Furina Lake Graham Lake ICRK at BlufoH Olney Reservoir (New) --- 1o Plum Creek No. 15 — ili,- HUM "r*ek No. 1" - ---Ho -- - -t*lner Lake-- Trib. of Rwlng Creek Lake Crwk C° *ndy Cr«« 5t**«» ^rwir Buf^*^* Unnajw^ Trib. Llttl* Cr««k Antioc- :r»-k _ ™ P rt- • at rorlc Trib. of Patoka RiT«r 3. Fork Pttoka River Tippec.no* W.er Mill Cr*«k in Trib. of Kidoan-aas Riyer— N. Fork Vtrnliion SlYer Trib. of fUccoon 3rcek 1 do *>"» ' Trlb of Veale Cre«k Trib of Flat Creek Trio, of Saat Fork 1b *% Dianal " ek Little Plum Creek do Trib. of Little Pljm Creek 1o 'Yib. of Pon-1 ..r-e* — -- T>iompsonTlli«, HI. Johniton City, in. — ^ in r' «est Frankfort, 111.— M K do 'anay farv, Ky. Sharon Grove, K/ ReedTvill K ' ' (^HIU HIrftR Huntingburg, Ino, Oakland City, Ind. tentisello, Ind. — • — Hltch«H, T-nd. Charleston, 111. Danville, m, Flora, 111. Ucled.. 111.— Washington, Ind. Bluford, 111. Otwell, Ind. Olney, 111. Taylorovllle, Ky. ® — fa "airfield, 111. .519 1.799 ^.85 2 7.62^ 2.86 .37 9.59 BASIN KOI SON TO Wabash Hirer Basi .67 .52 1,700 1 15.03 1.41 267 1.34 -53« 3.353 .034 ">.36 1.03 -56 .300 .512 1.725 3.75 7.288 2.85 .36 8.56 UKOHTOWN .63 .40 ,698 2/5.29 1.38 266 1.33 .531 31 3.199 -031 3.1) 1.02 .55 -'^ July June ug. Kay NOT. Kov. Jan. July June Oct. Sept. Apr. Sapt, Jun* June Aug. Aug. June Oct. Sept. Sept. Dec. 1957 1945 1960 1926 1922 1945 1964 1955 1960 1965 1964 197O 1894 1921 1923 1940 1938 1940 1941 1947 1915 1940 1938 1959 1928 1950 1956 1926 '960 1154 1954 1926 1956 1956 1960 1945 20 15 34 16 o.33 19.0 17.2 13.1 25.3 12 6 34 1,5 1,870 35.56 27.41 300.63 471 2,654.7 515.- 617 1/30.35 1/28.90 1,379.87 _~ 1,355-4 998 137 2/850.8 2/835. 8 aii.o 14,722 14,041 127 306 Z6O X87.4 171.9 4/8,643 7,438 49. OS 37.75 187.75 175,18 13.3 104,8 104.4 67O.7 10.7 10. (3 1,555.3 1,517.4 316.75 224.3 213.2 126.3 1^3.7 121.2 53.68 4fl.fc2 .295 .103 .079 .2*3 .195 .502 .296 .236 '.23 «.22 -15 .15 .33 .154 150 ".264 •2.116 •2.079 2.017 ".016 -.016 •.023 *.020 :: •.061 •.052 .044 .631 .588 .046 .300 .723 .706 .516 .268 .262 .254 .263 .25? .261 .237 38.3 51.5 48.7 35.9 •65 *eo 75.78 77. 7< 77.58 •40 •40 70 '75 •67 _ •70 72.4 •70 58.6 33.14 61.94 ~ 30.3 48.54 45 53 56 47 a. 3 0.64 1.06 .R80 2.41 4.6 y « _j. !/. 54 .617 1.937 2.490 .023 .975 ,140 1.75 .179 .40 — 2.46 .19 ,218 2.10 1.7O — 1.18 1.84 4.19 2.00 3.11 1-15 534 1,1*9 934 530 1,884.4 6,512.2 i/1,498 1/742 1/1 710 1/912 4 538 1,720 3,796 38 1,420 __ 213 2,760 273 510,5 — 1,775.6 256.35 1,460 — 1,247.5 1,803 4,837 2,439 3,180 1,034.3 IWS IWS IWS IWS sn scs scs scs scs srs scs scs scs srs 5CS IWS SOS IVS scs IWS IWS scs scs IWS ------- co l-»_io 17- a 17-22 17-73 1H-1 18- 2» l«-1e Ifl-flc 18-1? in-n 19-? io-3 19-4 10- So I/ ">*ii In *h« 106*1 y T*-« */ - IP •*• Scott aburg Uk« £agl*.. Kill (Cataract rfa >«t Falls """ — 1°" — to- _.. 7° 3O Wll °"~ ° 0 0 ° Pickwick Undi^ — •to 1o Dal« FUllow- ,*> J rf fto"0*7 Wolf ^r««k 'Lake Cta** U|m*r Gn*n Rirer *< ' _., ° rora F IttwLv, 4l* I — to M Pool or,'.? survny. •>»-< fro« ?2P ,"i """i o '!' tjo *nKfl r •'* ** t*k **T*do"r* Trlb. of Aueatatuck La**;-- Mill Crock j 1 Ittl Rl " it C*ney Fork River ao fto T Rl *""*"** 8r~ •to rin 1 ° 7° ° tn 1 ° do rtn do ° (to Obey Biw ,lo -u-*>«rtam1 Hlvar , . ^° JO pllot - South Fork — j_ *" stm*5 rte-°r c -JO _ Scioto Ri»«r ^_ ••am i- -h>ry Clo«d or 1 '.T'O ic. -ft. ™ l*» Ind. Seottgourg, Ii*d. ClovM-dal*. Ind. TOKE33EE RI\ HorAiosTlll Hvh-KJaia 1J.1.I. Ky. fto — — — Sock I aland, Terui. rto ~_ Cunt «irtll ^^ "'^ * do- •Vv Tow Cr»«k. Al«. ^° rto ao Fl 41 _A — *, do to "^^ ' T*""1' do d do dn " t*llb.rt»yille, Ky. ~~ do CelUia T«nn to- Old 11l.k«rj, T4.U1. 1^ ' do Palls of Hough, Ky. Stanford, Ky. OHIO RIVER BASI Kanaka, Big Sandy, Licking I~*nca3t«r, '• do flAJ Turd , Va . ^ ™- Dayton, Ohio ^ r*1 1o- l' ° do igfged li»e stone sinkhole-. .342 ".294 3.95 2.98 295 rER BASlf, (B rid and Ore. 2.1 6.10 1,675 24,450 29,590 __ 30,750 - 32 820 - 40,200 935 11,674 5,789 454 1.44 N (POINT ?U , Kentucky, .20 329 651 270 1,053 — .327 — 1950 — Jun. 1959 .278 — 1906 3.57 Oct. 1955 Oct. 1964 2.98 Fall 1949 Oct. 1961 287 DK. 1952 — FA. 1962 ELOV HALES BAH DAK) n River Ba.in* 2.0 liar. 1915 — »0». 1940 — Jan. 1941 — June 1959 1,671 S^t. 1935 — Aug. 1947 Sfl*. 1960 — No*. 1969 2,550 Ko». 1940 — Jun. 1947 — Hay 1956 July 1961 675,033 Oct. 1936 — Jun. 1947 — lay 1953 June 1956 1,135 0«. 1928 D«. 1931 — 0«!. 1936 — June 1951 — Au(. 1961 1,997 F*. 1938 — 3^>t. 1946 — June 1956 Auf. 1961 7,131 Aug. 1946 Hay 1951 July 1956 Oct. 1961 987 Apr. 1943 — Jun. I960 2,741 June 1954 Jun. 1965 5,690 Aug. 1950 Jun. 196) 437.56 OK. 1959 — July 1969 1.41 S^it. 1955 - Apr. 1966 EA.ANT TO MADI30NI Scloto, and Hiaan RiT.r Baeli .20 Oct. 1902 — S.pt. 1941 329 Aug. 1934 July 1944 639 — 1927147 264 — 1927147 1942 1,0*2 -- 1905 — 1935 1951 8/ 1953 survey revised. 9/ Used drainage area beloM 10/ Swtlwent contributing ar Uj Nljiue (-) indicates ecou 12/ Uncontrolled drainage ar 137 Including 19,000 cu. yd. 147 lMr survey -anges «re Estimated or assuned. — 52.11 9 46.5 53 54.50 9 2,409.8 — 749.02 12 713.24 i/232,370 9.17 2)0,906 — 1,31) 25.7 1,279 — 769 34 564 18.5 509 — 54,925 12.0 52,370 6.4 51,836 6.6 51,591 9.2 51,281 — 1,09", 380 6.6 1,080,897 8.9 1,073,164 5.1 1,064,228 10.7 771,071,717 6.0 8/1,061, 411 3.0 1,061,005 5.1 1,050,303 — 687,000 3.0 674,000 5.0 652,000 9.8 651,000 4.7 650,000 5.0 648,000 5.1 641,000 1,130,313 8.6 1,116,389 4-7 1,118,082 5.1 1,116,811 5.2 1,105,256 4.7 772|855!440 5.2 2/2,814,388 5.2 772,79O,«55 — 1,706,000 17.2 — — 467,000 11 453,703 — 6,089,000 12.83 332,940 9.75 329,670 — 320.71 10.5 316.59 114 J8.9 95 1,646 10 1 ,018 15 311,648 15 105,618 — 4,563 30 3,920 16 3,928 13 3.737 Halee Bar Dam (8,935 sq. «a reduced by eloeing Wh IT (treated as negative • >ea 2,776 aq. nd. dredged in 1930. established. .238 .212 .391 .316 ».7«7 •.76) •.294 •.280 1.123 1.116 .135 .099 .089 .024 .023 .OJ3 .022 .023 - 1.533 .8c6 .857 .23 .19 - •.810 *.8O9 '.554 •.552 .008 .007 .007 .007 mi.). —l.r Da. •diaent). 48.0 47.61 55 60.8 62.8 43 43 •60 •60 •60 •60 •55 •55 •55 •55 •55 •55 •55 •53 •53 •53 •53 •53 •53 •53 •53 •53 •53 •53 •53 70.27 59.9 - •70 77.5 1.89 .87 2.38 1.00 .54 .600 1.00 .495 .127 .050 .022 .02 .979 .141 .687 .141 .027 .417 S/.479 2/.490 J.120 .120 .401 .274 .811 U/-.180 .125 1.113 .719 1.107 .635 .441 .765 I/. 26 1372.50 .191 .037 79.5 .097 •65 .020 59.4 .014 i.Oct. 3, 1936, to 1, 1,975.9 902. 1 2,851 1,324.2 739 936 463 166 29 26 1,171 4O8 523 32 500 552.9 565.6 138. « 138.5 462.0 1,471.0 936 144 1,285 830 1,278 7)3 1,170 i'339 291 63 168 28.3 135 aq. 91. IKS ns SCS SCS SCS TV* 75* TVA TVA TVA TVA CE CE SCS SCS SCS SCS ODU ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W THE UNITED STATES THROUGH 1970 DATA SHEET RESERVOIR NUMBER STREAM NEAREST TO»N DRAINAGE AREA (SQUARE MILES) ) j TOTAL { NET OHIO RIVES BASLH (PO1BT PUUSAJTr TU XAEISOM lananfta, Big Sandy, ticking, Kentucky, Scioto, and tttaaj. River 19-6 °hl° Con*- K"** *> 73 Blacklick Cr**k Colu*w», Ohio ^ 24 jr* _, * ' ™'*- tJ- no. ,4 .to 19-Ba U*» ifclte— P*« D«« ~° An ^^ „ do -to Valto »^ L j_ j- 1 n D_1 1 ° • fH~ 19 1? Bjllewiy ww nir* llu 0'3hju*hn Sciot fi ™ •™*W1"""' do rtr rln Deck Lak Pa't *"; do j- j ,, (V«nt L«t 3 11 ™ ^"*n **" ~* do do d 19-17 Caldwell Lake Trib of 19-19 Pine Lake Tar Holl do do- ^ 19-33 Kweole Run (Trib. an of Bweole 11-23 Alien Lake Trib. of •*• do 2} Creek Waverlj, Oo^0 37-4 36.9 ii „ ** "alien, y. .^, .21, WilllaMaUju uutotai , Sy . . 4 , .1,7 Dublin*1 Ohl ublln, Ohio ^iSJ *rf/ ft Pioua Ohl n ^an 'T1*, (*hio ~. } -.30 •» London, Ohio 5,.~ ,,.0 do rJo Ml 3° • — un nt. Grab, Ohio ^j.^j ^4.97 rt d j Stonej Creek fcrerlj, Ohio 1.02 1.00 Chill 1° th Ohl ow Creak Gillaspierille, Ohio — 2.42 2. 40 do— L- - _- ' do K» Dublin, Ohto 13.8 13.7 Silver Creek Kenton, Ohio .50 .50 ^ do~ ""**• J 1.85 1.39 19-24 Sylwn Lake (Uf-pen do do .40 .38 19-25 Hoatermn Lake — Trib. of 19-36 Reynold* Pond Trib. of 19-5fl Scbott Pond Mb. of do d fed HiTer Sprin«ri»ld, Ohio 1.50 1.53 Bar-en Creek Bidwell, Ohio .70 .70 ^ — nt.^Ciload, Ohiu 8. ,} i/5.50 Bi^ »(alnut Creek- Westerrille, Ohio .82 82 19- TO ftaplo CTOT« Lake 3aB» Creek Mt. Gllead, Ohio 3.05 3.04 do — do do — — 19-U Pond Lick Lake- — — Pond Lick Run Friendship, Ohio 2.54 2.53 — ^° .40 .4 i ]«-«, HcBrid* -ak« — Trib. of Pnrd Run do - .61 61 | PERIOD DATE OF BETWEEN SURVEY SURVEYS {YEARS^ Basina {Continued/ June 1939 2.fr JM. 19'7 fc». 1939 2.8 Oct. 1935 — Dec. 1947 12 0 Aug. 1951 4 0 Oct. 1941 lo %7 193* 23.66 — 19344/ 9 — 19424/ « Julj 1951 9 Jane 195O 10 IStA — Jure 1949 2.6 June 1951 2.0 June 1954 3.0 D.,:. 194« — July 195O 1.6 Sept. 1957 7.0 Aug. 1962 5." July 1971 9.0 — 1937 — Sept. 1949 12 — 1939 — Sept. 1951 12.3 Fall 1938 Aug. 1950 11.7 Jan. 1940 — Jan. 1950 10.5 July 1954 4.0 June 1962 3.0 — 1925 — 1938 — Aug. 1951 13 Aug. 1951 1-8 1948 Aug. 19->1 2.8 Mov. 1938 Aug. 1951 12.7 1940 Aug. 195O 1J 1930 Oct.. 1948 18 1921 Aug. 1951 30 — 1901 S*pt. 1951 50 — 1932 — Sept. 1949 17 — 1938 Juljr 1950 12.3 — 19 J6 July 1950 14.3 193 c July 1950 15.3 1917 — 2.53 1.04 .52 3,734 3,338 i/3,706 2SP,949 *S5f?n* 128 122 113 1O6 8,892 3,538 3/16,67-* 15,604 14,538 14,162 115 ^4 594.0 530.2 511.0 486.7 1,140 1,111 1,068 1,027 965 88 85 74 71 134 123 3,215 3,010 2,929 2,867 384 7.3 4.8 774 744 28.1 23-9 48 39 25.4 23.1 Tl 32 13 *.D26 *.02i. *.023 *.022 *.084 -.069 .0564 .0550 .0529 .0508 .0478 '.120 .073 .06? .575 .539 .524 .513 •.029 '.006 *.OO5 .014 .012 .02i .019 .053 .048 .086 .083 .027 .02.. *9.0 1.5.9 49-9 52.6 44.8 *45 66.2 57.4 *60 57.1 ^5. 5 fl3.2 58.8 59.9? f>7.02 34.01 '.394 1.73 2.13 2/.184 .121 .135 .063 .913 .43 .17 .14 .721 .247 .324 .274 2.«D 2.48 .95 2.73 3.53 . iS .441 .039 .10 .84 .079 in 191 60.5 459 l^O 331 1,137 59S 2,*>10 2,144 3C^ 29H 2,664 3,400 548 551 51 124 1,015 143 35- 35r ODW ODW OOW ODW 3D* ODW ODW ODW COW OOW TOW ------- !-> 01 19-17 19-38 19-39 19- 4C .0-42* 19-.J. 19-50 19- n 19-53 20-lb 20- 2b 20-3b !' T ' • *" t ~A~ 4o w"r oc"in* ™°- - ^tt j 00 Lak , gu a e- **re~ W. n,. «11 Creek Reservoir (Wlnton Lake) C*~ k h ni" ^ r • • riulr Whit t Lak Ji»co Uk« j Lak A t Lak j Hi-Idle Pork Restrvolr " 1 ial Mln Lak *~ "1" S+°i M1 1 Ir r p t LMte- 5o H 1 to *ui:::::::::::::::::::::: do OI" rt ^^ d°~ ~w. 1.°" H Without 1 't. flashboards a-lde^ In i« Surrey lates Sept, -Nov. 1914, Sep'. 10"' rorr»c*lon for Marl* 'jfovs. Rf*r-v- r ivirtla ^ j 1red*ed -n Mar-'- *"-"" " eaK do Morgan Pork U*lt*d* """ ' ami " ak , 7° iia ~ k ''"rib. of :iear -reek Olentangy . irer- W Pork Mill Creek °"reek <* Trib. of ^ittle Salt Creek _M« k1° " A M. Fork or E. Pork White Water ReaervoLr ° "d'" f^t ~" i, n i -rcnk do Wat4u«a River do .. p n or o a n iver do A a d do- 0 Ar-1 34r. Oa-t on amount r __„ to° )hi ' ° d«- J.u.»,td,.. 'hi= -•ric*, *r, -.fi.o- d*i'i T° ~^ Wil i ' 1111 *rc * i1-*' h'° KiHsboro, 3hio *° Uelai«re, vfiiv. Cincinnati, Ohio Butlervllle, Ind. A°~ Jackaon, Ohio QC oo ° ' Jhio hcUMd. Ind. B«il h D< vl j r do iO.JO J.?.^D 4.45 4. '9 10.9 10.7 1 . - J. 3 . 42 1.87 1."" >a •> T> ,«.< 48.5 t>.60 6.4U .73 .69 3«1 379 29.5 2B.6 13.4 13.11 19.29 19.0 1.67 :.•# 6.88 6.72 "•* 1O6.5 AS. 14 47.87 1.05 1.00 .009 .000 TBWE3SEE RIVER BASIN (ABOVE KALES BAR 0AM Hampton, Tenr.. do „ do •lo do- do 1 19S1 surveys ar- not 468 453 _ 1,840 662 '..903 62 , Julj 1950 1'.3 Spring 1947 July 1950 j.5 Aug. 1960 10.0 — 1937 June 1949 12 July 1952 3 — 1937 — Aug. 1950 13 Apr. 1956 June 1961 5.0 1951 11 1960 120 — 1942 2.3 — 1949 ..0 — 19-SO 1 1956 1960 4, 1955 9 Ntr. 1951 Nej 1960 9.25 Dec. 19-2 •tey 1961 8.42 July 19 > 9.6 Sept. I .86! .612 .432 .79 .642 20.16 .249 .611 .609 .568 .430 .284 .520 .468 .012 .340 186 1.03» 820 22 963 940.711 "5 156 1,936 \720 2,104 923 1 .190 8/2O8 1,6»9 1,516.8 1,529 6-38 2,108 978.79 15,824 732 •>30 680 515 340 623 561 14.4 407 OOW ow OOW -CS OEM OOW ODw OW OOW OOW 3 s:s scs cow cow COW scs SC5 SCS TV* TVA TVA TVA TVA .241 2*9 .276 331 a*_er capacity at a-i' Iway cr«9* el.vatio-1. Til. to I,*?"7 oq mi. by closing o' katauga r D«c. It, 19------- Sl'MMARY Of RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH WTO h-' Ci DATA SHEET NUMBER 2O-6d iO-7c 20-8c 2O- 9b 20-lOfc 20-llc r-v; a-(= Ila Ionnc33.c rtlvcr do- - - - -o ^ T "hatug* Hiwaeaee Tiiver Bottelj Nottoly River •1. do do ._„: „..._ . !^l!^^*r"-iiiiiri"-~ -- "i^ ""inniiii "„! ""- lk) NEAREST TOWN . DRAINAGE -\REA •SQUARE MILES) TOTAL NbF TEMKESSEE -tl ,"ER r^Jv rABCX'i HALES dA>: DA«i ^ Jc - _ jo 10 ~ H-°,~, ~ , j0 ' . . - do - Unolr ;ityf Tenn. ^,550 1,;56 GlenvUle, N. C. 36. ^ ;-.,4 do do — Fontana, N. C. . , *TL ,.,426 do — do ,0 f!Z£::l'™:-~ ~Q' --" do 1 \.-rn, Ten- <,<^. ^.«'i _d^ 30 ao -0 _ fiayesvi- - f .. . -89 1 « --^— snr^ ;r-T-=: ^ 2^ -- --;--; 9- ^.r. ^o ?arne^ >nr. I.JI8 ^ 3, 'T" DATE OF 1 SURVEY (Continued Fall 1^1 ' (•pb. 1^33 Apr. 194" Oct. ^^ Jily 19i.9 Kaj 15" --•b. 19U Sept. 1-50 toy L969 Kar. 1950 Get. 196" Sept. Lu s.c 0.- c,.l 5.0 7.6 0.0 4.0 7.5 5.8 5.0 6.° 7.5 STORAGE ' CAPACITY (ACRE -I- 1 '21 T~ - ^^-1 12,010 "•."6C ,,1,32- ;i 5r~'^? :,49fc,"i2 400,9^= )98,OoO *" "'o =137 70,487 13?,159 i' Is'r-1 1 ,^,3,262 39,OjC 1.C52 1,580 .,347 1,118 2,047,527 2,036,324 1,195,229 1,17:., 954 242,0-2 241,502 240,516 3/176,521 175,865 174,429 174, i -7 2/439, "41 435,630 -.34,243 433 , ^68 57^979 ^7,75,- CAPACITY •\VG ANN INFLOW RATIO (ACRE-PT PFR ACRE-FT) .011 .00^ .OCR . JO6 Ct . 00 7 .002 312 .308 ,3Q \--> \ PER SO Ml • .rPL\IN OFNETDR i ATA AREA FOR PERIOD SHOWN ' AC -FT7 0,252 .2.:k .299 .32-> .107 .975 .lt>8 .83C i/-.251 .7 US .""CT — . -21 4 .181 .rili. .ol -i; — .28 i» .7^)1 — TONS " _ ™ At.1-, 126 35" 11" 82 183 '•VA ^94 — 895 "47 — TVA 25c il"? 807 TVA — 731 160 TVA 34C ^..1 — TVA .692 .6^1 .690 .689 .705 .704 .702 .701 .699 .586 .534 .581 *55 *55 •55 "55 *55 «55 *55 *55 »55 *55 *55 *55 .l&O .305 .155 .667 .589 .219 .595 .472 .590 .415 .758 .415 .GS7 .536 .132 y- 1,401.7 337.6 186 799 706 TV* 262.3 712." 565.4 — TVA 497.1 9O8.0 521.0 104. u TVA 8/-- 125 642 213 1,124 l,-58 ------- 20-2Oc 20-21d 20-22d 20-23c 20-24d 20-25 20-26 20-2? 20-28 21-1 21- 2a 21-3* 21-4 21 6 21-^a 1, T 6/ it ±LL/ nldge- io H° Ocoe. .to. 3 do •° - CO do do- do- do do ° C O. 1 0 J do ^ UgQ do do do rfC H do oo do- Oaceola Lax* Melton Hill Upper Ollis Creek ^e^ervoir — ,0 Senecaville Varies "ill riinckston nun Juemahoning 'alt Lick . Srirt^eport (Uope") do • Prior to 1925 dam was 35 ft. lower. Original volume comouted froa prooin ed from dam closure in 1913. Five fo Revised. in Mar. 1944. Blue Ridge Reservoir closed 3ec. L , Hi occoa i er i Ocoe. Hiver J° Co do do do.™. do- ao- 10 Tenressee River " "° r,° "° rto Shepard Creek Clinch River ' ^ do Seneca Fork t R nincKDton un Phoning Creek Salt Lick Run Jacobs 3reek j d° Ducktown, T«nn. 496 0 0 rf TJJ do— do — d Chattanooga, Tenn. 20,790 0 ^ 0 do- Clinton, Tenn. 3,343 1 1 T o^ e, aim. OHIC RIVER 3A5IH { ABOVE KJINT PLEASJU do — Senecaville. C hio 121 do — Mansfield. Ohio ao . p T 1C, ° * do- 92 do- — Ht. Pleasant, Pa. 18/31.64 £3 obtained Feb. 1933. Pediment deposits and nater inflow •ot lash boards removed ^ept. lao,,. • -napa. 1930. Oco-^ f> closed Aug. 15, 1942. 227 Apr. 19*4 — — Aug. 1949 5.3 Aug. 1954 5.0 Apr. 1966 8.8 263 Aog. 1942 — July 1945 2.9 - MOT. 19*6 1.3 — July 1953 3.0 Oct. 1955 2.1 Oct. 1958 3.0 — Oct. I960 2.0 Mar. 1968 2.6 10/96 D«*. 1911 — 1 — Oct. 1940 28.3 — 3«pt. 1949 8.9 - Aug. 1954 5.0 14/1,805 »OT. 1940 — — July 1947 6.7 — Ifcy 1956 1.8 15/990 Oct. 1935 — _ Oct. 1940 5.C July 1947 6.7 — Aug. 1954 7.1 — Kay 1956 1.8 — June 1961 5.1 Dec. 1967 6.5 1.50 — 1908 — — Oct. 1956 48 4.39 — 1923 — Oct. 1956 33 422 July 1963 — Maj 1970 10.75 Apr. 1964 — Oct. 1970 0.5 JT AND LAKE EB1E DRAINAGE 195 Oct. 1938 — — Feb. 1945 6.25 113 Oct. 193612/ — — Xar. 1945 8.3 207 June 1938 - Sept. 1946 8.25 July 1954 7.75 ^0.57 — 1905 — — Sept. 1937 32 90.7 Jan. 1912 — Sect. 1937 25.8 Sect. 1937 2' 13/31.52 Mar. 1887 Nov. 1937 50.6 — No*. 1964 27.0 12; Volume computed by average end conditions. 137 Volume computed from contours 14/ Sediment contributing area redi ^ara, Feb. li., 1943. 15_/ Sorris Da* closed Mar. 4, 1936 contributing area to 99O »q. mi. l^/ Determined during 1956 survey. Conservation Service, U3DA. ley Original data revised. 1964 s from transit survey (1963). *> estimated or assumed. 197,427 196,080 195,981 196,522 195,908 14,304 12,140 11,349 10,570 9,849 8,696 8,042 6,766 5,920 5,286 4,653 4,026 .1/109,200 12/91 , ?OO 11/86,737 87,267 86,809 16,466 746, 95i 734,970 745,178 740,367 738,320 153,483 152,928 152,251 152,992 153,032 154,002 154,012 16/246 190 125,900 125,578 461 649 87,700 87,424 88,500 87,667 88,000 85,886 85,483 3,453 3,315 35,295 34,413 .462 .454 .454 .455 .454 .017 .005 .091 .0056 .120 .093 .055 .045 .0429 .0428 .051 .050 .076 .674 .962 .953 •.657 •.641 «.638 2,432 - 642.0 .016 453.0 .011 338.5 .008 area method from first ar cased on 1949 survey. uced by closing .atts Bar , and ^hickamau^a Dam clos ranges established and sur •55 •55 •55 •55 •64 •64 64 •64 •64 •64 •64 •64 •64 •64 •64 64 •64 •64 •64 •60 : •60 •60 •60 61 •61 •61 •61 •01 43.1 45.7 •55 •62 •65 •65 •65 •65 •60 •60 65.4 curate ar Dam on Ja ed Jan. 1 veyed IT. 1.119 1,340.5 .881 1,055.35 V--498 — .308 368 2/2.114 2/2,947 2.312 3,223 1.646 2,294 1.3T3 1,914 1.460 2,035 1.1B3 1,649 1.616 2,253 1.608 2,242 1.388 1,865 .753 1,050 .916 1,27* 4/-1.10 — .974 1,358 .406 566 iy— iV— U481 1,935 .168 220 .102 135 4/-.105 — V--022 — V--192 — i/- — .780 732 .428 426 .109 131 .172 232 .227 321 .89 1,260 1.24 1,755 .253 358 .408 533 .~fn — .22 287 18/.L18 168 .134 191 ea— volume curves - , n. 1, 1942, and Apa] c, 1940, reducing si Dec. 1937 by Soil tion and topography TVA TVA TVA TVA SCS SCS TVA TVA CE CE CE SCS SCS .achia idijaent ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1»70 OO 1 DATA SHEET NUMBER I 1 RESERVOIR STREAM i NEAREST TOWN i | | DRAINAGE AREA (SQUARE j [ TOTAL KLES) DATE Of SURVEY NET j PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT ) CAPACITY AVG ANN INFLOW (ACHE-FT PEB SPECIFIC rciGHT ;DRY> LB. PER CU. FT) AVG. ANN SEDIMENT ACCUMULATION PER SQ. Ml, OFNETDB AREA FOB PBUODSBOVN AC.-FT. TONS AGENCY SUPPLYING DATA OHIO Rr.Ef- 8ASIN (AF^VE PI INT PLEASANT) AJ»D I UE EHIE DKA1NAC2 (Continued) -" 8 71-9 n i" 71-11 21 16 a.m. 71-19 71--V a-?2t> n-TO> ,! „„ 21-27a ?\ ?S ?i --»o ] ^ ?1 >l-''4fc Sarbertim Wolf >«<* Barborton, Ohio 2S.2 Puckey^'aXe s- ?o-* '-Ickin* Riw MUl«raport, 5hio 1/49.2 Le«»vlllfl- tGuire >e«k LeesrUJe, Ohio 40,0 -,o — do do — 'to - - T ih OM Rl do I1 Onto Cons. Pond No. SI- rrib. o. hio iver- 3hlo Miia. FtmJ HO, }*. 3~ 0 "• *" T ' v fifi '" i to P 300 x>rl«y5 Lake- ri , o. oi^n.ogn ny n on , d°~ 10 ui * DM ->p< •; i-ue fiocKwll y 3 ,^^ Stony Like McGwire Creek-^ — > — Perrysville, Ohio 11.75 ~''° ° -. Tabor Slub Lake Snail br. tt.skinguM R ver- do . 56 do do do do do do LoyaJhanna Lcyalhannfl Creak Saltsburg, Pa, 29C j - -- jj do GO MahoninK Creek-- Ma^orinR -reek Dayton, Pa. 340 do 1o do " " 'ri " f T-H Cit P5 277 ^ga-t River Tygsrt River Grafton, -*. 7«. 1,184 do • do do ~^° R " f P Toughlo^henr H,»#r oughiogheny iver ' , Atwoor" Reserroir Indian Fk. , Conottou "re«k Sherrodaville, Ohio 70 110 ^ Rl hft Irf Oh 02 Babb Pond Unnamej Icnrl* , i ° >1 17 do -io -do ^hrlstener pond no Parma, Ohio .09 ^°~ " 1 h*1 .^hufinbowlc ond o lcn.1 , hio ^ df • i k^ "h do do- do- do io do 28.0 45-.1 A5.7 .31 3/1 "4 1 "^ 11. --2 .54 2.93 285 336 — 1,179 — 4*;8 66.2 .09 " __ 7.4S - __ MOV! D«c. S^pt. June June Aug. Oct. Apr. Apr. — pr. July Aug. Dec. 1926 m 1936 1939 1915 195C 1927 1923 1938 1936 1941 1949 1942 1941 194B 1937 1940 1951 1940 1949 1955 1969 1935 1956 1961 — 12 36 ll.o 15 8.0 7 10.2 5.9 14.2 6 5 2,056 2/19,940 37,400 37,390 9. U 6,88? 121 61 53.6 42.4 133,400 132,571 .5/95,300 6/74, 20C 289,600 49,700 3.24 3.40 1.29 2.B4 1,511 1,451 178 134 131 -.101 ".083 •1.159 • .159 .042 .116 .028 .025 - •iii5 •.034 .210 .209 .276 .180 .177 .307 .307 ,175 .405 .994 .991 .019 .015 .016 ,058 ,076 ,066 .027 .195 .187 .025 .OC2 .021 __ •55 »5O •68 "60 46 •65 •65 •65 •44 43 *65 51 *fc5 •65 •65 •60 •60 •60 "60 •60 74.8 _ 17.9 -- .067 .151 .135 .120 .319 .156 VI. 38 .326 .203 .358 .326 .178 .062 .277 .341 .29 -15 .281 .611 .567 .100 .442 .213 .199 .466 .078 __ 73 224 120 452 1,500 462 287 343 272 167 87.0 30ft 106 483 410 196 367 798 741 131 720 — 164 SCS SCS SCS SCS SCS SCS SCS ODW ------- 21-36 21-37 21-38 21-39« 21-40 21-41 21-42 21-43 21-44 21-45 21-46 21-47 21-48 21-49 5. Br. Cuyahog. liver Trill, of HehonUu Si»er- Alliance, Oh] do- Berlin Center, Ohi Broad fort Bun — Trlb. of Sttidy Creek Ml. Lake Park, Hljwrvm, Ohio—— Hilton, Ohio - Lvica.t«r, Ohio Logui, Ohio— Orchard Pwk, ». I.— ElngKood, ». C«t.rrlU. Mil. Uk loungatow., Ohio- do Salem, V. Va. «• Fork rredvrlcktoMn, Ohio— — Lwcijigton, Ohio •lellijigton, Ohio jo Logan, Ohio— leehiia Creek Site f2 FranklinriUe, ». T.— 21-5) 21-54 I/ Drainage are* has been 115 sq. «1. (n«t) part of the tine in the past, when fed partly by feeder from S. Fork Mrkerwille River. 2/ At present spillway eleTatlon (lowed in 1908). Pro* 1836 to 1908, spillway -levation was 893.4, surface area 3,636 acres, and capacity 22.09O ae.-ft. Pro-i 1832 to 1836, spillway eleTatlon was lower and surface area was 3,13« acres. Natural lake of 650 acres origijially. £/ Oa* failfl earlier In 1938 but little sedinnnt lost. S/ At elevation 7"^ rJ.«»ation top of gatea - 97* ft. S' At e'.ev&tion l,lo^. KleTatinn top of gates - 1,164 ft. 8.66 — — — — — — — — — — — — — — . — . — . — — — — 16.88 — 8.22 — 246 — 7.4 — .07 — .12 — 277.4 — .11 — .58 — — — — — 10.38 — 81.76 — .29 — — — — 1948 — 1949 — 1950 — 1951 — 1952 1953 - 195* 1955 — 1956 — 1957 1958 1959 1961 - 1962 1963 — 1964 — 1966 1967 1968 — 1969 1970 — 1939 1mm 191.9 - 1913 Aug. 1950 July 1943 •OT. 1951 — 1880* July 1957 — 1931 1938 — 1930 — 1938 — 1916 — 1941 — 1946 — 1954 — 1930 — 1948 — 192H Oct. 1951 — 1902 June 1952 — 1855 — 1949 — 1929 1949 Oct. 1954 Oct. 1956 Oct. 1958 D«c. 1960 — 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 2.0 1.0 1.0 1.0 7.0 1.0 1.0 1.0 1.0 — 9.7 — 37 — 8.4 — 76 — 7 — 8 — 25 8 — 18 — 23 — 50 — 94 — 20 — 2.0 2.0 2.2 30.66 uAaii 1949 — — — 19.79 — — — 32.05 — 6.12 — U.17 — 2.75 — — b.iX — — It elevati« Aug. 1960 July 1970 "ay 1954 July 1955 July 1960 Aug. 1966 Oct. 1948 Aug. 1956 July 1962 Mar. 1956 June 1961 Feb. 1955 Aug. 1966 Aug. 1964 July 1967 Sept. 1969 Aug. 1964 Aug. 1967 i;epl. 1969 >n 920. Spilli 7 10 — 1.2 5 6 —. a 6 — 5.6 — 11.8 — 2.91 2.16 — 3 2.12 ay cr*ot •!< 234 217 206 202 199 197 193 192 187 183 177 176 170 166 163 159 150 148 146 145 142 4,659 4,535 994 933 — 91.200 122.75 77.02 .15 .0 .11 .00 28,100 22,250 9.46 9.11 11.5 4.65 169.99 161.26 144.8 117.3 86.3 38.3 32,400 31,835 69.58 68.95 68.77 68.60 3,502 3,399 3,283 1,111 1,092 1,059 1,009 13,176 12,886 12,731 760.4 745.5 3,142 3,081 465 464.72 464.33 1,085 1,083.77 1,082.95 tvation - 9 .037 .035 .033 .032 .0)2 .031 .031 .031 .030 .029 .028 .028 .027 .026 .026 .025 .024 .024 .023 .023 .023 •.340 •.331 .551 ~ .010 .004 .597 .586 .265 .262 .261 .261 .146 .142 .137 .0642 .0631 .0612 .0583 .565 .553 .546 .190 .186 .291 .285 .156 .156 .156 .159 .159 .159 9/55.7 9/50.6 "S/53 3/55.6 2/65.3 J/68.2 — » — — __ — — — — __ — — — — — •40 — 66 •100 — — _ •65 — 65 __ •65 _ 43.1 __ — . — to •50 •65 — •65 •60 — _ . *80 80 — *«O 80 _ . 1.00 10/1 1.27 1 .45 .34 .25 1 .41 .14 .55 .47 .64 .18 .37 .42 .33 .45 .55 ,22 .236 .136 .319 — .759 — .20 1.30 2 — .081 __ .29 .08 .84 1 -_ .36 __ .657 . .23 __ .117 _ .0493 — .346 1.09 1 .31 .27 — . .48 .378 __ .787 .341 .419 — 1.13 .806 — .435 — .363 — .0345 .Ob65 — .Oo5 .062 ,03 ,177 693 609 .239 926 - — — — __ — — — — — — — _ — — 661 — 287 ,830 — — _ 410 113.3 _ ,199 377 __ — _ 300 _ 127 — 69.6 — 489 — ,424.4 405.1 352.8 — — — — — — — — — — — — — — 60.; 116 — 113.3 108 ODW ODU DOW SCS ODH COW ODH ODW ODW SCS 3CS ODW ODW •rs ODW ODU ODW ODW ODW SCS scs 2/ 8/ In view of the United «jwunt of M-tLMtnt computed in the X94S report (384 He.-ft. ), the vtluaa of the 1945 report &re not included And were not used In computing eurrey d»t* for the 1959 reoort. It is considered that the longer period (21.5 JT.) waa necesBstry to develop * voluBe c«p«bl* of being measured with & rttaaoncble degree of Accuracj. 9y Density for antire period of record. 10/ Computed from differences in totil sedlnent accuntilation in tons »t each vurvvy U/ Gate closed Pall 194?. Drained Karch 195C. Oate closed Jtaj 1954. * EstijButed or aaeurMd. ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 19TO to o DATA SHEET NUMBER 'PA-4 •a -58 Salem - 10 21-S9 Uprer ri -ic 13-? ">..ronac 22-4a Auglaiz dc 0 do dc dc dc — - dc dc 22-1" •IjciT 22 1 a Bu.t i-= 22-14 Kohart 22-15 Vio <5u r\( 22 lo -Jorvel ic ?2-17 5ba-on 22-19 irookl; 22-20 Iron Md 22-21 Phoeni3 22-22 Sa-ine 22-21, artdge 22-?< Prankl 22-26 ' I'-e-1' I ; j i ' ' RESERVOIR STREAM i NEAREST TOWN DRAIN4C ' (SQUARE i TOTAL ork No. 11A Varr.er Hollow alei, *. Va .288 ockiug No. 1 Hunt-pr* -"Jin -anca •?•,<•-, Ohio 1.04 ^:^5^-,. :.^M . _ . . _ aL - ------ 1o ^ pine P.. of "tanistee liver- *ellston, wich. -91 POIld do - - -ao - e P.. Power Auglaize ^Ivar dc 2,329 ° J° -d '^ 3 do do — IT "° O^ "1 "fl ""'S ^!!I_!T lo do-- ..!: - — io — ^ . ^nat., ri , 3. j do do -,-esk5/ Sixmile :reek Defiance, Ohio '1.6 ' , - ,f0 d ^h ?^ nn , Pond_ _ __ L'-j.amei Oro/er dill, ^hio .021 e- Jake tocky Ford >->sk -indUv, Ohio 22. PO io — - ^' Lake Hi', er ".aisin '.'o" /ell , ''o.s'i. 59. 5 Hollo* 4o Manchn->*. : , v:ch. ^^.7 TI Mill Pond do Brooklyn, tch. 29.6 <*o io 11 ftond Iron Creek—— -do 1- U c "ond Middle "iver Houge ?lyrcwuth, Mich. ^.-^ vill ?oid Saline Ri- er- Saline, Mich. 'I?.6 jay lake Unnamed Dexter, 'ich. ". 5 dt, -do n ^11 Onnd - - - Pranklin Branch Houep - — "ranklir, "icn, "" - . J rri Vr,-- Middle River 2ouge — Northville, 'ich. r4 . io do i ! JEST TOWN DRAINAGE AREA (SQUARE MILES) i DATE OF SURVEY i PERIOD ] STORAGE BETWEEN SURVEYS (YEARS) CAPACITY (ACRE -FT.) CAPACITY AVG. ANN INFLOU RATIO (ACRE-FT PER SPECIFIC »EIGHT (DRY) ;LB. PER CO. FT.) AVG. ANN. SEDIMENT ACCUMULATION PEB SQ. MI. OF NET DR. AREA FOR PERIOD SHOWN AC.-FT. TONS AGENCY SUPPLYING DATA Aug. 1962 — — .237 — .94 — July Oct. Oct. Oct. Dec. June Apr. June 1967 195.* 1956 1958 1960 1962 1956 1962 4.9 — c 2 2.1' 1.51 — >.a '1AbW-? RIVER BASIN 93 23 1 .024 — 2,326 5.20 — 1.91 — .012 — 37.0 .035 — 2.79 — .13 - -"1.4 — .7k — .019 22.72 — — 25.3 — 25 — 6.2 — 6.4 — 5.2 — 56.8$ — 63 17 __ 7.5 7.8 — __ *ug. Jan. tfer. Aug. — — Julj _ Aug. AfiC. July — June July Jan. July — June — — July Sept, July Sept July Spring Nov. AU?. — Hay — fej May •fey — Aug. b.pt. Mar. May — Mar. — »pr. 1844 1940 1912 1953 1945 1951 1912 1951 1912 1951 1912 1951 1947 1951 1941 1149 1951 1945 1951 1919 1949 1947 1951 1962 1912 1951 1943 1951 1943 1051 1939 1948 1951 — 1969 1927 1969 1948 1069 1945 1969 — 1969 — 1969 1937 1969 1906 1969 1927 1969 1833 1969 96 41 t>.k — 39 — 39 39 — 4.3 — g,3 2.1 — - 6.7 — 30 — 4 6 — 39 — 2.3 7.8 — 9.5 2.8 — . 10C.H — 42 21 — 23 — 100 — JOO — 31 63 — U — 136 Sept. 1969 100 JA30 106 ./u 11 1 1 654.13 653.89 53 52.25 52.O5 51.95 51.75 450 U6.13 ,175 ,605 6U> 27 9.5 9.1. ,400 ,600 129 74 U8 104 2.6 2.5 991 929.1 902.4 5.03 ». 71 242 218 9.2 7,0 7.4 6.3 975 696 59 57 2.4 2.3 248 205 186 717.6 502.3 258.1 143.9 249.3 1B6.3 288.9 259.5 ,551 ,159 225 170 240.1 129.6 a. 33 10.9 76.7 47.9 97.? 13.1 173 101 .21 IiSe .166 .165 .165 .164 .882 .875 *2.193 •1.796 J.003 ".0001 '.761 '".753 .012 .009 .050 .029 «.15t *.109 •.417 •.401 .Oil ,049 .046 ».239 «.22I .120 .108 .133 .114 .10? .091 .094 .066 .155 .150 .229 .219 .022 .019 .017 .026 .018 .016 .009 .016 .012 .09 .08 .224 .168 .0074 .0056 .0061 .0033 .0026 .0013 .0250 .0156 .Olj3 .0018 .067 .0039 •55 110. 4 W.5 73.4 53.2 •53 53.7 43.4 57.8 •49.3 43. f 37.2 26.1 53.6 57.9 23.3 30.1 43.4 31.5 41.8 44 38 46 50 39 i/o. 01; 1.3O7 1,706 455 209 .348 .16 .443 2.64 .064 .92 .031 .27 .59 2.75 .34 1.71 .2fi 2.10 !969 .36 1.13 .53 .20 .31 .065 .11 .434 .20 3,162 154 902 - 347 675 4,396 232 392 2,001 277 3,270 1,460 343 924 301 233 391 43 72 457 137 .75 -OO97 .057 .01 OQ3 .079 .013 SCS 535 ODW ODH ODW 03W ODW COW ODW ow ODW ODH ODH ODW SCS 5CS SCS SCS SCS SCS 93 86 n ------- to 22-27 22- 2P 22-29 22-30 22-32 22-33 22-34 24-l» 24-3b 24-4a 24-5 24-6 24-8 24-9 24-10, 24-11. 24-12 24-1 ^a Jl-16 24-17 24-20 P4-21 24-22 34-23 11 TpcnmiHi fill Pond Belleville Lake Ford Lako Barton Pond ~ — ''ill ond M. H. Fry Pond — U J. -*. I I,' o urgh a o AH 1 c JVdrion Lake WilUa»on (Artie Pond)- do do do do H° T^ to Lake Decatur do Shaefer Pond ™ Lako pringfiold 1° Brack on do do Lock and Dara 2^ (Winfield) do do Mt. Sterling Lake Jacksonville do do do • Lanj^don Pond Franklin Ou.ine ~ub e do Nav-rly City Vo Roodhouse Park District Lake- rtoodbine Co'im-y Club Lake , ? " Dale _ole c.ii 3e«ly Por>d — ;j -is •)?n(i,'x) ac.-'t. •" C ok " M13 r° Huron River j 7* zz3rzzzzzzzzz ppor Squaw Creek do "^ r° reefc MISSISSIPPI H Trib. of Honey Creek )to do /• ' "rc do ' ,„ Sangaaon River A Trib. of Cahokia Creek „ 3u**r J^1*1 i r 3 "*" ^^ re ru ro do Mississippi River fa. 00 7° Trib. of Shelby Creek Sandy Creek do Unnamed do- do • do 0 j do do do do _ do rt ri J° rjQ — Belleville, Mich. 810 T 41 * * i« 1_ T«-. pau.an , men. fyu Ann Arbor, Mich. 708 Qnrtead, Mich. 12.45 th l« if f c . 5t-J Adrian, Mich.— 65 26. 3 — 1827 20.3 — 1929 — July 1969 11.2 -- 1933 183 - 1915 — July 1969 12.45 B«rly 1962 — S^rt. 1969 59 — 1942 GREAT LAKES DHAINAGi U« MICHIGAN AND *I3QONSIN) IVEE BASIN (LOUISIANA TO CHESTER) ILLINOIS, KA5KA5KIA, AND MERAMJ Carlinvllle, 111. — -- .53 -51 — 1922 u j T-il £1 "°rto rto Sa T A ' ' do Decatur, IU. 906 rt Edward sville, IU. .087 ° _, pring , -do- Winfield, Mo. 1^2,000 A Hn do Mt. Sterling, IU. 1.90 Jacksonville, in. 10.8 do — 32.6 •> -io PVanklin, 111. .358 0 Waverly, 111. ^.^i. do — Hoodhouse, 111. .-.51 *'*) jrocnrlcid, Hl'lTlm '11. .093 60 Dec. 1929 — tag. 1952 — July 1955 25.79 Jun. 1939 July 1954 Sept. 1959 902 Apr. 1922 .083 *>». 1937 July 1949 258 Jan. 1934 Aug. 1946 20.1 Apr. 192? S^>t. 1947 8.85 Dec. 1923 — June 1949 — Dec. 1946 — July 1939 Hay 1945 Deo. 1947 Ifcy 1959 1.75 — 1935 — — 1951 10.1 — 1939 June 1952 32.2 — 1921 2.72 — 1900 June 1952 .348 — 1907 — July 1952 July 1952 9.16 Oct. 1938 — July 195* July 1952 .439 — 1917 July 1952 .120 — 1926 — July 1952 .221 — 1924 July ' 952 .091 — i«S V rrlbut-.-, .,- 6/ Ul flg------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 to to DATA SHEET NUMBER RESERVOIR 1 STREAM NEAREST TOWN DRAINAGE AREA (SQUARE TOTAL MILES) NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG \NN (ACHE-l-1 PER SPECIFIC VE1GHT ;DRYJ LB. PER CU. FT.) SEDIMENT ACCUMULATION PER SQ MI. OF NET DH AREA FOR PERIOD SHOWN AC.-FT. TONS AGENCY SUPPLYING DATA , KASKA3KIA, AMD KERAKBC RIVK8 BASINS (Continued) 24-24 24-25 24-30 2A-11 24-3^ 74 JY 24-38 24-39 24-40 24-41 24-44* 24-45 24 47 24 4B *•-" TineyaM Pond Knapp •lo do -ah«lal, runt] do • • • •: B * Q 1. R. Lak«- Bduarda Lake — <3o : : . "fa Klnmind do do Pa L^kv Buiikc ril I L*ke Gilleipie- Uke Nashville Lake Staunton do ""V ^° ^"* A Parana Lak* Po*»r Fan** °onds— n ~° i v. C°A^ ^^* Pn if" rt do — *, Walton lub k« Lock and Da» 26- — * do do do Jnnaaed do Aw tf ** Trib. of Sangaacn River V In Irf Tr-b. of Kaakaskia Ivar- ^° Loa, -rcofc: K* ska ski* River "Vlh f Gahoki '" elt * ° -r«ek !• f? nooa tu. or 3ry Pork Nashville Cr*ek ~ r ky*n JI" 'rtn """ d ° Trib. of Indian Cr*«k Trib. of Sanganon River — - 0 ^ I, Hac.oon .rook "° ok -erra -ro Trib " r " k " j^" ° dc Hiasiaalppi River -do . j° -lo dc- Whlt«hall, 111.- Springfield, 111. a4 •a am. BrwnsJl k Irw1 "^ ' TalliOa, 111. do Gillaapie., IU. V A 1 < Til anoolia, 111, R rrlll I1! Gillespie, 111. Sashvill*. HI. Staunton, 111. do— Urlinville, 111. ~... * Panam, 111. Cantrall, Ul. r- 4. n T-n *" ' * ° 111 • * *" -L-ai — : . ' Alton, 111. • — do do J*° do do 0.054 3.49 -i -it -.. ', .85 ' ' 5. ^3 1.39 3.68 .85 .668 fl 48.4 " in ,4?o -- 0.052 3.43 l * T ^.JV .84 .40 , • .4« 5.62 1.13 3.5. .84 .666 — - ,_ — Jan. July . un July j , u«. - Jul May Hay Dec. Oct. 1937 1907 1906 1^A7 1902 1952 1949 1923 1936 1926 1954 1928 1940 1QT3 1950 193S 1945 1945 1947 1954 ' 50 57 - 28 in 17 7. 1. 16. )3 15 1.58 181.8 ?9 44 a 31.7 15-4 74.2 ^09 320 1,243 1,140 IT?. « 116 395,000 390,200 406,200 85,231 .053 .093 *062 *"cT6 .067 .033 .351 .272 .3^6 .6^0 .575 .536 .011 .003 .260 .136 - .0017 51. J 49.3 28.1 54.9 46.8 -W) 4A 4 _ - — — " 9 .39 1.09 1 76 1.01 .36 .70 36 2.70 .73 - .004 — 419 667 996 1,130 430 406 713.51 2,352 769.5 - — 7WS IWS IWS IWS IWS IWS IWS IWS IWS IWS IWS rws IWS TWS IWS TW* CE CE ------- ro»l ». 19 (Uto MlMlMlppl KiV KIHISSIP-I airai BA5i» (rAimoirf TO LOUISLUU) toi«. Stoat, «nd D.. fctn.j U'«r Bxliii low— 119,000 479,550 to co 25-2 25-3 25-4 25-5 25-t 25-7 25-« 25-* 25-10 25-11 25-13. 25-U 25-15 25-1° 25-17 25-U 25-19. 26-1. 2*-2 24-3 27-1 27-2 27-3 27-4 H *• IteCrwMr »•* •— Bvailtli Buia a.vll * do do r1 dn •-fltt*^" L*Jw { PoTMtvlll., •t t If* Mill ~ dn ^^ ' f i *• =- iri» i«i "mo do !i , — IktOAMd Tl-ih t* m " *- ^'^ ita ''•* no do rt Tfe 1 Ml «i lnoi to T* *Q.T*r do i r° JUW HJ.IM do OPPBB _, " do * "~ on do Ihqnok*t« River ^^ do * "i". owwr Cr««k W 1 ™* ConMnvtion Pool. All 31 rugM MMW •oaur, partially du* to re«ov*l of bon Splllwy r«lMd 2.89 ft. in 1946. Origin*! capacity MS do ^_ An Elnrtarhctlk HI ' j _ ^rt* ••w Cant-on ' ~^ ^' do HA^COfi, toW 7° ^U*"~» lwl* Pkli-flolil j Qnthrl C«vt JUUVl* LHILU r 1(IIM KUC.UI.., Io«. 111 UU1DCT, *•"•• * K»« ^1 IJ, Io>« do 13.9 13.1 13.8 13.0 2.94 2.88 52.0 50.2 15.34 15.24 77.0 4/72.7 77.0 66.0 31.8 2.54 2.05 2.1 99,400 134,300 2.25 99,600 135,000 3,115 4/72.7 i/59.6 31.6 2.52 2.00 2.1 — Z.13 3,076 WSSISSIPPI RIVER 8ASIH (PRAIRIE DU CHIZN TO SOCK ISLAND) A Rock and Uapilpinicon River Basini Rock laland. 111. 88,500 io do j d d° SlraiAsrrT Pt. , Ioi« — rto Dubuqu., Iowa UPPIB HISSIS3IPPI RIVER Wlaconaln, Root, Ch " do^*' lBC" • .. l\. u* A' 111 Wi ^L^**do 3C' Pr»iri« du Sac, Wiac.- MS.6 ac.-rt. All sedimentation - 116 81,600 BASIN (ST. ippeua , anc 60 50.75 138.6 fl,900 - 116 — PAUL TO '1UIRIE St. Croije River 60 50.73 138.2 6/600 4/ Excl 5/ Excl ?> Flo. June 1939 10 Jun. 1946 8 Sapt. 1947 13.3 S.pt. 1924 — Aiic. 1936 11.9 Julj 1947 11.0 kmr. 1926 A««. 1949 23.4 Dae. 1936 D.C. 1939 3 — 1941 2 1924 — Klnter 1932 t 1921 1936 15 Dec. 1936 Dae. 1939 3 Dec. 1939 3 1935 ln*6 11 1918 15 1934 J«lT 1953 19 Har. 1938 *>v. 1949 11.7 Oct. 1937 — Hov. 1950 13.1 Sept. 1937 Sapt. 1951 14.0 «mr. 1954 15.6 K«r. 1954 15.7 Sapt. 1958 Jan. 1964 5.33 Apr. 1968 4. >3 HO LAKE MICHIGAN DRAINA Har. 1934 Au«. 1938 4.5 Nov. 1944 6.2 Dae. 1946 2.1 Hov. 1948 1.9 Nov. 1950 2.0 Nov. 1952 2.0 Jul7 1934 Feb. 1942 7.6 Fab. 1949 7.0 Apr. 1938 Feb. 1953 14.8 DU CHUN) Baalna — 926 Oct. 1541 15 June 1939 68 Juni. 1939 72 — 1933 19 udes 3.8 aq. mi. Kiaala udea 5.B aq. mi. Miaala 312,216 660 452 273 - 308.2 •2,400 - •1,664 738 552 3,000 1,845 3,080 2,556 •2,800 •2,290 1,154 1,070 43 25 207 166 135 185 172 113,370 87,740 - 896 831 70,800 78,040 69,570 492,000 485,400 4«0,110 SE 39,432 39,224 37,881 37,086 608 473 683 457 < 127 46 1,677 • 683 • 91,851 — aippl River bottom alppl River bottom " .145 — .099 «60 - •50 •85 "85 .148 .111 *60 •067 .041 *85 .068 .057 "85 .059 "85 .069 .064 *65 .069 .040 «70 .303 .242 '51.6 .198 51.6 .386 — .359 «50 -.616 «*0 . .46 40 .46 45 - 75.1 .018 .012 »70 •80 .022 .009 72.5 •90 land. land. 1.11 .977 1.12 1.45 4.U 1.06 1.52 1.06 2.41 2.85 .24 .476 2.96 .795 .638 _ 2.16 .001 .004 .402 .397 .002 .001 -.005 .009 -.001 .004 .078 .082 .014 .252 .023 .100 .717 •1,490 1,190 1,370 1,5»0 7,740 1,960 •1,990 1.960 4,460 5,280 340 726 3,327 893 695 2,823 — 350.2 443.2 - 127 134 384 40 158 1,4OO SC& ns IMS SCS SCS SCS SCS SCS SCS SCS SCS SCS CE 3 SCS d CE CE CE SCS CE SCS SCS SCS CE loss data b*Md an higher opillwy «levatie>a. * Eotimated c ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 CO 27-5 27-6. 27-7 27-8 27-» 27-10 27-11 27-12 27-13 30-1 10-2 30-4 30-5 30-6 30-7 30-9 30-10 30-11 30-12 30-13 30-14 30-15 30-16 30-17 DATA S8E£T NUK3ER RESERVOIR 1 STREAM | NEAREST TOWN DRAINAGE AREA (SQUARE TOTAL MILES) ! PERIOD DATE OF SURVEY NET STORAGE BETWEEN! CAPACITY SURVEYS (ACRE -FT.) (YEARS) CAPACITY AVG ANN PER SPECIFIC (EIGHT DRY) La PER CU. FT.) SEffflMfTtT ACCUMULATION PEB9Q. ML OF NET DR. AIEAFOR PERIOD sacriN AC.-FT TONS AG8XCY SUPPLYING DATA UPPSB HSSISSIPPI RIVES BASIH tST. PAUL TO PRAUUE DU 3HIDI) WSCOKSIJf, SOOT, 3HIPPIMA, AW) 3T. JBOII RIVER BASIN vConti™*l) Prt*h»it Pam Pi Stalpl.ttgh r*™ Pond Hjfcl*1!*! Par-i Pond Wold Pan. Pond rB-28 Structure aaet Willow E-3 Itanalnk— 1.29 1.181 .26P .230 .384 .193 .433 July P*b. do Kov, Mar. 1960 Apr. 3964 Hay 1958 Jun* 1962 S*pt. 1957 Mv 1962 Julv 1955 Majr 1962 Ao«. 1954 Jan. 1962 Oct. 1954 Jun* 1962 MBJ 1956 Mar. 1960 Apr. 1964 UPPEH MISSISSIPPI RIVER BASIM (X80VS ST. PAUL) LAIS SUPERIOR WO) LATS OF THE W30DS AREA (II W1WE30TA) RED RIVER Cf TWE HURTH BA3IM ;»*- Bronao« Blabon TH« °!^-:±-zz-.ii--i^: nviimar 3»* • do '*'***? rik ' r°"d Magnolia Da» io r%"jon 31dln«; 3a» MalHrln Ballarud Fara Pond do , „ Pterb, o«_ I.* Item Ralalgtl D..* Sioux R»tlro*'l iUawfoir B«ld*iUl Out ''I^ika A*ht*bul*) HCMM Du (P»i-k River) Lake o' '.h« Otnrka (Bapi«U ^. 7hi^Ui«. n. Hi™, Ott.tr Till Kiv-ir Trlb. of GOOM Ri»«r M. Br. Por«8t Siv.r '*"* .^"r Trlb. of Wild Sic* Hivw— 0- T* _! d^ Buffalo Crselt Ruah Rlvar do d Trlb. of Wild Sic. Riv«r— Dog Tooth 3r««k Park River Trlb. of Wild Ric« Riv«r — 3h«7«nne Rlvar — S. Br. Park Rl»*r Trlb. of Waal NodaWtf Rlvar BroDaon, Minn. 4o Fr*»»«, Him. ,10 Blabon, N. Dale. Adama, N. Dak. Owinnar, N. Dak. . j ti n L, t^C' ' Havana, H. Dak. Ral«lgh, M. Oak. Ad&ma, N. Dak. Vallay City, N. Dak. Park Rivar, N. Dak. "CSSOURI RIVER BA! atantort, Iowa do 439 210 1.219 20.2 3.755 .226 27.76 12,16 30.2 1.125 14.375 .181 4.45 16.855 37.0 i/4,138 229 SIN (NEBRASKA 14,000 .166 438.5 1.188 14.6 3.670 .222 27.76 11.72 30.2 1.121 14.356 .183 4.45 16.66 21.06 2/1,979 229 CITY. TO KERHj 13,900 .163 Oct. Oct. Aug. Ma? Jun* Jun* Maj July D*c. Jan. Jan. Mar. INN) Peb. Oct. Juna 1*V 194C 195C 1926 1952 1935 1955 1935 19^7 1941 1955 1936 195fc 1939 1956 1908 1956 1912 1956 1942 1955 1934 1955 1934 1956 1909 1956 1911 1955 1938 H» 1958 1953 1958 1931 1948 1938 1949 3.4 4.1 4.1 6.8 4.7 6.8 7.3 3.83 4.08 $8 168.7 166.5 164.1 110.5 104.5* 14.27 13.29 19.O9 18.04 27.98 26.71 10.50 10,03 56.79 55.18 292.2 291.0 287.2 .474 .468 .461 .345 .327 .166 .155 .313 .296 .227 .217 .157 .150 .444 .431 .340 .338 .334 •90 — •70 •TO — •65 49.5 __ •45 — •55 -- 51.86 — •65 — •50 •50 - __ 0,51 .43 — 1.23 .52 .96 _,. .49 — .331 — .48 _ .11 .30 - _- 778 656 — 1,741 560 1,359 — 5*7 — 374 ~ 6AO — 120 330 CI SCS scs scs SC3 SCS 305 3CS SOS 3,792 3,626 155 137.1 13O.69 107.29 150.7 139.6 38.70 33.36 12.92 10.29 22.82 19.10 157.92 127.40 43.15 35.40 16.78 14.47 66. S9 46.19 5.227 4.467 175.47 145.23 88.37 69.16 1,995.6 1,808.8 76,400 75,410 3,650 3.382 — — — — •3.354 •2.753 •-2O9 •.194 •.284 •.245 •2.494 •1.986 •.026 *.022 •.406 -.328 •.045 •.037 *.412 •.355 •.128 •.089 •1.191 •1.018 •.925 •.766 •.145 '.113 — — — .204 .189 32 •90 •90 .03« .029 .98 .034 .101 .59 .0078 .052 .0058 .1579 .0676 .188 .144 .026 .2167 .0981 225 __ 25.6 12.6 __ 875 — 18. al 76.99 372.6 5.95 39.64 — 4.44 114.68 51. 93 — 184.3 109.8 18.88 — 151 192 — 441 SCS scs scs scs scs scs scs scs scs scs scs scs scs scs sea CB CI 17.8 10.9 1,972,531 3/9.46 2.59 .283 -.231 •.063 .464 598 3.87 4,200 a scs ------- BBS 8883 888838888838888 S 8 2 S 8 8 8 S S C 8 SRC8 8*8 5 43 8 ' ' ' ' ' ' 1*1 1 "1 3 n I Sift 5 I 3 If If 125* I 3 ISCIflfclPlflflllflJIflEIS If 1333 1333 1333 1333 1333 I S IS I d If I SiRS^S* & 2 SI 38 * 3g««8S53IS2 35x1 .• .• , | .' .•^^jSp.-.-j!.'.'.'. .,,!!,.... I3! 3SB^ -- « O r4 O O" ** H -* *-<-l ^ *• 'tai 3.aiJi*inss i» i Ja is i* i< 1 a i-* i OW«^ P~*^3 N 8 "* isia iaij i"!-* i" id is i*4 '•* i"' 'J i™J>4 i (VNP-1 is i !* IS8I8 i | J | « |^| ^ | ^ | | | ~ | * | |" | ' | ' | •< | •< |» | ' | ' I ' I ' | ' . ' | ' | | | ' I I I J I I I ' I I I ' I ! I ' I ' I - I ' I"' I I I I I I I S-3 BSSS £8 S ' ' ' 3 § S P3 I a I - I " I "' I ' I • I 1 1 " I *' I I ™ I ' I ' I J I "' I •*' I ' I ' I ' I ' I ' I ' I I I I ' 1 1 I rt I I I III III I I " I I * I 1 1 I I r li I i e Mill i • :a ;? . 3 g :- | iiK It I 111 58- •J , " c u B! it I I w is h <-* • l^ B R rt B sa ssstsasas *|* «c------- SUIDIARY OF RESERVOIR SEDDIEMTATION SURVEYS HADE IN THE UNITED STATES THROUGH 1970 NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL ] NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG- ANN (ACRE-FT PER SPECIFIC fEIGHT [DRY) LB. PER 01. FT.) AVG. ANN sfmffxr ACCUMULATION PEBSQ. ML OF NET DR. A1EAFOB PERIOD SBOWH AC.-FT. | TONS AGENCY SUPPLYING DATA to (CSSOUHI RIVER BASIH (NESHASXA HTT TC HSRWV) (Cent nu«i) n-3t n-3? n-«o n-u n-u n-u n-45 n-47 n-w 31-52 31-53 31-54 31-55 n-56 n-57 31-5H 32-1 32-2 31-4 »-» 110 "~ %lrl^ rwal ^ *" Tl WLMII ^ dp* _ do "" * do oo Rl«la»vlllo Old Cltj UJw Trlb. of Carlo Crook do *- .fc do d, - -—do J»it33nb«rwr - *>- Ljji SI1 T lb r tail**! a'»«r do do fa*«r — Trlb. of *»»h« Slvw Cosily Cr. tot^r*- (C-l)- a-u-cl^ Bnnch dp — do do— — -do ^ r-o.,^111 Muarlxud i"_ . j«. ** THh 3t l_Mht r Mfc to — ^do — — RM«r do 81*1 SOD . ,_ao — — do LfjMm — . Trib. of KM Cr^k- Qko Cum lU^rTOlr Trii>. Bull CrMk f_1_h'*? _.. ^ WBiniUoUi ruiLl oo ltljd.mjiiul Lit OTT 1 oti to 4o H»1I ftMMl *rib. Litti* 3u^r JohtMcn Port do Pltam jomttf Hat* -»K« -r Shvrtdui CooBtj SUt« Uk* 3*»llj,e Rir«r^ • UtBKtoo JUMi-Tolr Sicily Crttok • • ^° , jj rt B^^T^ mr^lr ^ ** do * ^n * UfJrwiJ* K*n« . ' do* to 1 s """ HM^ll..*.— do do aiohl^d Kan.. Zt»dor&, K-m». • ifantuttan, Kana.— 3*b*tS' K*n***" ColtQobi*. Ko. do- .-. . Holt Etui do do '- • G«n-*tt, Kan». ftrk«r, fan*. — Soj*,or, to. Edgorton, Kana. SichBcnd, Kane.-. Bluo Mound, Kana do — S"OKT HILL AND I " " ~Jy?°n' Quinter, Kans. Kanopolia, Kans Boatrico, Nobr. do do .18 18 1.17 3.78 2.728 .334 .119 .23 .125 3.20 .284 5.62' — .83 .16 .28 .23 1.17 .19 .77 .57 .86 .38 AVER RSPUBL 20.47 493 ^,860 .52 .67S - .18 .18 1.16 3.75 — 2.633 .117 .22 .122 3.14 .280 5.515 .82 .16 .27 .23 1.16 .19 .69 .50 .84 .37 .93 ICAN RIVES BA: 20.26 463 3/2,560 .512 .661 .171 Oct. fer. *>». "ay Oct. Sopt. Apr1! Nov. Apr. July JoBO July Sopt. July Oct. Oct. June Jan. "ay Apr. "ay Hay June Spr. Apr. Apr. Aug. July July Oct. July Pali July July July June June July July Sopt. Sept. Sept. July Peb. July July SINS Apr. Aug. AUJ. July Sept. Hay' 1957 1939 1956 1947 1955 1946 1957 1937 1949 1951 1955 1962 1968 1924 1964 1950 1964 1949 1962 1950 1962 1937 1962 1955 1962 1949 1965 1956 1962 1967 1967 1969 1971 1936 1967 1958 1968 1957 1968 1956 19M 1936 1967 1961 1967 1960 1970 1960 1970 1955 1967 1955 1967 1936 1967 1929 1937 1937 1948 1946 1960 1936 1956 1947 1956 1937 1958 7.7 17,7 6.4 11 12.6 1.4 4.3 6.9 6.1 39.8 13.8 12.67 12.4 25.1 7.1 16.33 5.9 .25 2 1.9 31 9.75 11 12 31 6 10.2 10 12 12 31 8.0 10.8 20 8.75 21 50.86 20.86 19.05 1/3.78 2.42 1/29.13 17.7 290.48 212.01 2OB.14 202.23 186.07 171.52 520.0 304.0 32.26 25.55 7.94 6.73 6.77 6.26 tt.D 54.27 1/7.52 5.68 206 176 1A3-" 11.32 1,017.07 1,010.8 989.3 974.9 19.67 11.06 18.07 16.18 64.35 59.98 31.26 27.3 22.8 14.1 6,7 6.16 204.3 191.1 14.683 11.03 232.86 222.06 46.22 42.87 24.03 17.3 1,001 930 777 436 446, COO 436,320 33.101. 14,704 30.5 22.22 8.058 2.301 - - - — - .103 .259 - — .05 .03 .39 .35 .80 .74 .47 .41 .049 .03 .08 .06 .607 .568 .061 .045 .68 .65 .25 .24 .05 .039 r •60 86.7 62.01 •60 69 68 •68 69.4 64.7 55.94 58. ^4 56.8 47.9 46.7 56.2 75 50.7 41.6 53 58.2 •60 •60 •60 67 60 •60 •65 •60 •60 •60 66.5 •50.0 •65 •65 •65 1.88 .56 .90 .90 1.44 .73 .36 .62 .62 2.061 2.686 .«5 .07 1.27 2.13 .58 1.61 4.57 1.94 1.38 .34 1.19 1.47 1.43 .24 .47 1.88 .77 1.07 .76 .24 .438 .0681 1.77 1.400 1.566 2,457 1.057.5 1,201 1.1^6 2,178 807 543 1.038 614 2,511 3,436 1,051 73 1,294 2,609 947 1,777 4,144 2,379 2,059 444 1,555 1,921 1,869 350 614 2,457 1,090 1,398 993 313 98.6 294 2,506 1,982 2,217 SCS s:s SCS AEJ. AKS AI3 SCS SCS SCS SCS SCS AttS SCS SCS SCS SCS SCS SCS SCS SCS 3CS SCS SCS cz SCS SCS SCS ------- a a n s 8 g B a a g B s g s 8 s a 8 n B s e 8 8 g g s B 8 s a a B s g s B § s . ' I J I - I ' I » | •> I ' I ' I ' I ' ! ' I ' I •* I " I J I ' I "' ! ' I * I H' I ' I " I ' I ' I ' I ' I ' I " I I ' I ' ! I ' I ' I ' I ' ! ! a"--J«^gg^Ri}ggR*gMpsirtgi|ssJiiBSsi8a3^^^"S**!'**a'^ ^ efe^ 5 *O ° ^ - "' I | | ' | ' | ' | ' | ' : ' I - I ' I H° I - I ' I ' I ' I ' I ' I ' I ' I ' I ' I I £1 ' I 4 IJ I ' I ' I 4 I ' I "•' I "' I '! '! ' I I ' I ' I "' ! •"' I ' I ' I ' I || ' I ' I ' I ' I ' I ' I - I ' I - I - I ' I ' I ' ! ' I ' I ' I ' I ' I ' I ' I R I ' I H' I H' I H' I - I H' I ' I H' I H' I ' ! H' I ' I ' I ' I ' ! ~ I -«' I ~ I ' I s" I ! 11 iii iirntr i •lil ill i liil J jisiJlimi iijijiiiiHiiiiiiii "p si 5 5lI33s3al?§5SS?O3§XSs§l§?ISiS§II??l3[I^I F-27 ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE HI THE UNITED STATES THROUGH 1770 DATA SHEET SVMBEP RESERVOIR STREAM NEAREST TOW i DRAINAGE AREA (SQUARE MILES) TOTAL i NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -IT.) CAPACITY AVa ANN (AOU5-FT. PER ACBE^T) SPECIFIC (EIGHT JWY) [La PER CU. FT.) ACCUMULATOR PERSQ.Mt OF NET M. AJtEAFt* AC.-W. | TONS Aoncr SUPPLYING DATA SWCT HILL AH) LOUE2 KSPUO.ICAI RIVSB BASIftS (£ontlnu*d) Trtb. S. P. Sol 2.32 1.61 .67 .59 16.93 Ifcr. 1954 A«J. 1970 Jar 1954 J»l7 1970 B0T. 1960 Jon. 1770 Aug. 1970 Jan. 1954 ImLj 1970 %j 1922 "•J 1966 16.4 16 9.6 12 332.12 307.5 12.896 6.8 127.1 123.3 69.32 63.64 J9.05 24.52 2,180 1,455 3.519 3.271 .058 .030 1.088 1.053 .389 .357 .331 .276 .68 .45 •65 „ •70 __ •60 __ •60 — •65 — •70 __ 0.65 .24 .59 .12 — .a — .96 _ 917 - 361 767 _ 162 — MO — 1,463 SCS SCS 3CS SCS 3CS 3C3 UPPBE REPUBLICAN, KJ&TH PLATT1, aiVtt BA3IM3 (FT. LABAKIE TO NORTH PUTTS) AM) SOUTH FUTTK BITD BASH (3UBLETTB TO •BRTK PLATTI) to oo n~3 u J3-3*. H« 3V4« n 33-5« Gi n-6 n 3V7 B* 33-fc a« 1>9 D« 33-10 ?> 1V11 * 1V12 3t n-i3 P' *3-U Be U..L1.LOTI _.tu. HII My 1 UUOULJ 11 IHM irrr Strwite L*k* ((todloln* Ktdleln* < CrMk Du) * f. CLatt* Bli d GwriM5 I«br "So -_^ 11 Kb .MMhfin *«««rvotr— Trib. of &*publla*n ftlivr- B»rtl«yf N«br.-— - — ill* tin 3«ixrTOljr-- --• n j '* rtB *"rTO Tiavl ••J1 J ^ -1 iioh*lt Stock Pond mbmba P jd "* ^* <5r ° P ^ ana PMMI *rto^*V n_ j •rOU'^_ftlnd •*l*tow-Pfcrtc«r H-l H'I oli^i 1 Stock Pociid do Trlb. of 1 do Uhnwd— Trib ^B**' * * ** Trib 3« ITl ,^3«PH B r "do°* *_*!. I Trlb. Joni toad— Willow Cr. 3«l«wlek J«W Cr«k- i«prtlle&n B] EftBt Curtis C w Crw* " **k P* r r r« Itobmv, »*r. , M ^ L 11 ! Jo _ * dfl1*' — — AtMDod, tan.. — — - No t° b. j— * * Atwoed JUn .' °' it G«njon Cr««k — HcDoiuld, Rani.-' — Draw c,, « , "** ° ' J°10' Lodg.pola. Krtr... .500 .497 - 3.*A 3.09 Apr. — 1.59 1.57 — — — Jan. — 1.41 1.4 «OT. ^f' UC1-. — .83 .82 HOT. Una — 1.5 1.5 Dor 19)7 1939 1952 19*9 1951 1962 1956 1946 1956 1936 1956 1949 1953 1958 1950 1957 1948 1970 1958 1970 1948 1970 1958 197O 1963 1967 1952 1967 5.6 12.9 2.16 11.17 16 10.4 X 4 4.9 7 21.8 11.6 21.8 11.7 4 464 15.64 8.83 92,817 90,920 88,663 9.71 4.89 419.5 381.6 106.2 56.0 11.00 10.10 9.12 22.12 20.69 18.19 9.74 72.48 63.17 20.96 13.82 111.25 1O2.01 387 337.4 27.68 23.88 .229 .129 1.691 1.656 1.615 - — _ .968 .541 .683 .596 .329 .215 10.053 9.274 •1.92 •1.67 1.20 1.O4 •65 .66 934 57.3 .206 257 71. A 1.34 2,084 70.3 .3! 475 •TO ,6O2 918 •70 1.18 1,800 •70 1.58 2,4O9 • ii 75.6 .392 645 80.4 .28 490 •70 .28 422 •60 .24 320 •70 .07 105 •70 .96 1,467 — 1.6 — •75 .17 277 SC3 BE SCS SCS SCS us SCS SCS SCS SCS SCS SCS SCS MOUTH PLATTE RI?EB BA3UI (ABOTE FT. LAHAKIE) SOUTH PLATTBH RIVEK BA3IK (ASOVS SUBUTTZ) 34-1 34-2 L*tc« ChtMMJV South Platts R. auid Gooso or last P«rlr Cr. , Colo. 1,766 166.9 — 386 — ~ 675 — — „. — — — — — — ,460 — i/Aug. tor. June Jan. Feb. Jan. Ju. Jan. ab. »b. an. an. ulj Ju.i« D«o. Oct. 1890 1933 1936 1918 1939 1127 H31 1933 1935 1937 1939 1941 1944 1947 1957 1966 1900 — 43 — 2.25 1.00 — 3.83 2.00 2.00 2.10 2.00 2.00 3.00 3.50 9.92 9.40 — 3,834 3,126 9,802 9,710 9,424 73,810 67,840 65,050 62,940 60,930 58,430 56,600 53,180 49,150 44,800 4/45,228 79,064 7". 5 75.6 60.7 54 .106 .741 .26 .20 .18 .23 .17 .21 .21 .103 17! 1,220 243 107 SCS SCS 77,958 ------- ** | I I I I || I | H M | I H 5 2 p;i<« "I'll M r ill H i f tf «l i u inn Will I I §11 II II II II M II II I I II I I 1^ I I I II I I I I I I E ly.1 I,-I iplpl ..iSl 8 s f s ii K 'st g s g a s h * u b a Sfi«s'SE59 :: s 3 * '- » s V< ff- Ul O -O O • F ^ •* ui -4O4 PHvi^BOiH i icii ii ii ii M ii ii ii i i ii nip) i i ii i i i i i i 3 i-i i~i i pi pi.oi 2i S '" '• it w • » a *" ?' «' •»' Sl Bl ?' F1 P ' I'l? lii ul> k s at sc is l Zf\ Kj.|^-l „! f,| ffl f,t,p\ r ~K He tk i a fcs etc s - - .I I I I ..I I ..I I Mj-l it* 'y'n 11 li li iisi li i iii a i H . I. I. I. '. I. '. \* MM M a a a a a B a B a a B a i wi C -* to M 11^i^151 ii5i3iJiai3iiiaiSi B 8 B B B B 9 B 8 B B B B B B B • • ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL j NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG- ANN. (ACRE-FT PER ALHfc-KIl SPECIFIC tEIGHT PRYJ LB. PER CU. FT.) AVG ANN SEfflUFNT ACCUMULATION PER SQ. HI. OF NET DR. AREA FOB PERIOD SHOWN AC.-FT. TONS AGENCY SUPPLYING DATA T w o 35-25 35-26 35-27 35-28 35-29 35-30. 35-31 35-32 •>5-33 35-34 35-35 35-36 35-37. 3^3« 35-39 35-40 35-41 35-42 35-43 35-44 35-45b fcller Fan* Pond- KLSSOUHI RIVER BASIN (A3CV-: 3LAIR TO NEBRASKA JIT:) PLATTE RIVER BASIN I.EZLOW UQPTH ] Trio, of Dead Horse Creek- Loup City, Nebr. Trib. of Oak Cr*«k Farwell, Nebr. Cook Hea*rroir- Ingweraon Heserroir No. 1 Trib. of Papillion Creek— Arlington, ^hr. Turkey Creek—. Louisville, Nebr. O'Brifn Rasermlr- O'icill 1 Trib. of L. NoKha River— Dunbar, Nebr. • — South Cedar Creek Manley, Nebr. Trib. of L. Mewaha River— Syracuse, Nebr. Russell Creek Unadilla, Nebr. L.79 .354 .26 .1RO .383 .209 .073 . '31 .779 .257 .15* .412 .130 .326 .100 .086 .113 .09° .074 .29R .177 -3'S .3?3 Aug. Aug. Aug. Aug. Aug. Aug. — — — — — — — — — — — — — — — — — — — — — — — — J«ly Oct. Sept. Oct. Jan. Oe=. Feb. Jan. Jan. Jan. Jan. Jan. Jan. Mar. Aug. Oct. Sept. Oct. Jan. Dec. Feb. Jan. Jan. Jan. Jan. Aug. June July Oct. Sept. 1948 1953 1949 1953 1949 1953 1952 1957 1934 1957 1952 1957 1952 1957 1954 1957 1916 1957 1946 195? 1949 1957 1937 19C7 1936 19^7 1949 1957 1954 195^ 1939 19=7 1934 1957 1936 19C7 1948 1957 1949 195? 1954 195b 1957 1958 I960 19L.C 1962 1963 1964 1965 1966 1967 I960 1969 19^4 19C6 1957 195S 1Q6C I 1969 1954 1956 1957 — 5 — u — u — 5 — 23 5 — 5 — 3 21 — 11 — 8 — 20 — 21 — a — 3 18 — 23 — 21 — 9 — 8 — 2.33 .92 l.CP 1.33 .92 1/1.00 .92 1.00 1.00 1.00 1.00 1.00 1.17 — 2.1? .92 1.08 1.33 .92 1/1- * .92 l.CC 1.00 1.00 .58 2.75 — 2.33 .92 15.6 13.9 15.40 14.39 30.74 28.03 11.78 9.93 29.4 21.1 12. 1' 10.19 .^2 .19 18.73 17.01 61.5 11.2 12.8 4.33 14.48 10.92 22.09 7.28 35.69 23.98 35.76 32.35 3.18 2.96 5.04 1.40 2.30 1.60 7.63 4.38 8.12 6.71 12.7 4. U 43.9 42.0 40.? 39.6 38.9 36.5 36.0 34.7 i/35.54 34.45 ?1.97 32.81 30.88 31.37 55.3 52.6 51.8 50.3 47.6 47.1 45.1 43.5 44.6 42.7 36.5 39.89 40.069 76.2 73.8 69.1 •.163 -.145 *.811 •-757 •2.135 •1.947 — — — — — — — — — — — — — _ — — — — — — — — — — — — — — — — — — •1.109 •1.061 •1.015 •1.000 •.982 *.922 *.909 «.876 •.897 •.870 *.807 .828 .780 .792 •.684 •.651 •.641 •.623 *.589 •.583 *.558 •.538 *.552 •.528 ".452 .494 .50 — — — "65 — "65 _ •65 — •65 — •65 •65 •65 •65 — •65 — "65 •65 •65 •65 — •65 — •65 — •65 — •65 — •65 — •65 •65 — 73.4 73.4 72.3 58.7 60.3 2/60.3 69.5 2/60.3 2/60.3 2/60.3 2/60.3 2/60.3 1/75.5 — 72.6 69.5 59.2 67.2 55.3 2/55.3 62.1 51.8 51.8 51.8 51.8 I V71.64" — 53.9 66.1 .20 — .71 — 2.62 — 2.01 — .921 1.89 1.43 — 1,71 — 2.90 — 2.93 __ 2.72 — 1.77 — 4.29 — 1.27 — .725 — 2.31 — .272 — 1.55 2. 04 3.57 — 4.63 11.40 3.11 2.99 14.50 2.99 7.85 i/-4.66 6.20 13.99 4/-6.22 10.91 V-2.372 — 3.31 2.55 3.64 5.52 1.55 5.11 4.73 4/-2.8S 4.92 16.91 I/-1 5 . 704 V--298 3.28 15.50 263 — 1,005 — 3,709 2,646 1,304 2,676 2,O24 — 2,421 — 4,233 4,148 3,851 — 2,506 6,073 — 1,798 1,026 — 3,270 — 385 — 2,194 2,888 5,054 — 7,400 18,200 4,900 3,800 19,000 3,940 11.8PO — tt,140 18,370 — U.328 — — 5,200 3,900 4,700 8,100 1,900 6,150 6,400 — 5,550 19,OftO — — — 3,900 22,300 SCS S^S SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS SCS JGS ------- CO 35-50 35-51 35-52 35-53 35-54 Oak-Mlildle Creak *>terAed 51t« 67-» Split Bock- 36-3 36-4 36-5 34-6 36-8 ' Ditch Old Dealltlnj; Baain Ifcstere Unoer Reservoir- I/ Adjusted to correct oreviouo ye 2/ Based on Decker I960 sample. i/ fond dry when surYeyed. 4/ *Sjnua (-} indicates scour or conpaction, (treated aa negative sediment). 5/ Weight datemined by ^nim proop. •fc do Trlb f Ifcl C ofc ' **" !*- do do rto rto (to do ~o rto rto rto d ° rto . Plmtt ° rto rtn A rt Horth Platte R Trib. of Big Sioux RiT-r— """rto Faraera1 Ditch Trib. of Clay Creek *> Unnamed rto zn2=zzrjzz:^i- j rt rtn rror. 0 ^ '° 1 0 — do do A rt H rl '7° ,o -° ^° ,o H° 10 d° rf -° *, ° ° -d ^ °K vozad, «br. rt j° ° ° 7° ^° Dwight, Nebr. — IVER BASIN (NIOBRARA TC ABOVE a ta, ow:l 0 0 Bronson, Iowa Mayfisl-i, S. Dak. Volin, S. Dak. Hapleton, Iowa 0 ^° H ~.~t-~--~-~~: 1° H °~ — — Dec. — ''eb . — — Jan. .063 .O6C Oct. — — No». — — Sept. — — Jan. — — Jan, .819 .''96 Oct. - Sept. — — Dec. — — Feb. — — Jan. — Jan. — — "eb. — - Sept. .49 .49 1.13 1.13 — — Oct. .89 .89 Jan. — — Dec. BLAIH) JAKES ASD BIG SICUX HI 41.3 41.1 July _ Jin* .593 .572 Dec. — — Feb. 22.9 21.4 Apr. . 408 . 4^ July 2.46 2.45 July .178 .169 Dec. .196 .186 Mar. - - July — — July .075 .069 Har. 6/ Includes upstream 1960 1960 1962 1963 1964 1965 1969 1955 1956 1957 1958 1960 1960 1962 1963 1964 1965 1966 196' 1968 1969 19<5 1956 1957 1958 1960 1960 1962 1963 1964 1965 1966 1969 1939 1964 1948 1964 1940 1964 1940 1964 1958 1964 VE» BA 1938 194° 1=>40 1949 1950 1913 1941 1945 1947 1953 1951 1953 1949 1950 1951 1952 1952 1949 1950 1<=51 1952 1949 1950 1951 1952 struct 1.33 .92 1A.OO .92 1.00 1.00 4.11 1.08 .83 1.00 1.33 .92 1.17 .92 1.00 1.00 1.00 1.0 1.0 i.ce 1.00 .9' l.CC 1.33 .92 1.17 .92 1.00 1.00 1.00 1.08 25 16 24 24 GINS 10.9 8.3 2.4 5.? 6 2 .79 .87 .73 .60 1.37 1.01 1.31 1.42 .98 1.30 ures. 67.8 _ 06.9 — c.4.9 — (.4.1 — cl.b — 63. 59 59.88 57.58 19.4 • 18.6 •] 17.7 • 17.6 • 17.1 " 16.3 • 16.1 • 15.4 *1 — — 14.7 •] 13." * 14.361 13.793 13.751 103 100 ?7.4 97.2 94.6 93.2 90.8 88.7 _ 86.0 80.5 73.867 ZA.°i .72 - 16.18 13.06 - 5.97 4.99 15.7 12.7 - 175.7 59.8 61.9 55.2 2/55.2 58.0 57.8 65.44 i/65.44 .470 — .409 77.2 .341 57.8 .333 72.8 .295 44.5 .235 56.5 .220 2/56.5 .167 60.3 56.0 .114 54.3 .038 54.3 .088 54.3 .045 5A.3 .042 5/69.5 .595 — .578 64.4 .563 64.4 .562 64.8 .547 55.6 .539 55.7 .525 2/55.7 .513 59.4 51,1 .497 49.9 .46-5 49.9 .423 5/66.29 — 104 — 70 — 95 — 95 — 3.90 1.98 6.69 2.60 8.42 4/-6.19 11.49 1.71 — 13.30 17.9O 1.50 5.83 15.30 2.67 12.17 0 11.43 17.32 V-7.767 9.467 .65 4.17 3.98 .40 2.39 1.93 2.61 4.21 4/-2.02 5.46 6.86 1.055 — .05 .21 — .08 — .11 — 5 2 8 3 10 1 22 22 2 5 18 3 16 13 20 U 30 6 5 2 2 3 5 5 7 13 ,100 ,700 ,000 ,120 ,640 — ,048 112 — .400 ,500 .400 ,600 .900 .300 ,000 0 .500 .500 ,196 ,756 — ,000 ,600 600 ,900 ,300 ,200 ,400 ,900 ,500 ,419 -~ 113 __ 320 — 166 — 228 — 899.0 692.1 78.G 70.7 69.1 67.7 8/674 275 4.09 '.37 25.19 20.10 37.95 5/38.20 35.25 34.10 34.80 38.1 37.8 34.4 34.4 8.45 8.45 7.88 314 242 394 347 335 326 178 073 157 .129 .160 .128 949 955 881 870 870 866 859 782 782 497 497 464 464 46.9 1.54 •57.8 1.82 57.8 .98 •77.7 •77.7 77.7 •76.1 •76.1 76.1 •72.7 •72.7 72.7 20.1 1.67 1.25 17.96 8.41 0 — SCS 8,064 1,580 2,300 1,240 7,300 411 1.2A6 34,015 6,211 2,070 29,768 13,319 0 2/ Water 3Lcoly pool capacity. Reservoir capacity is greater at spillway crest elevation. 8/ Conservation pool capacity. Flood pool capacity is 1,952 ac.-ft. 9/ Increase in capacity in 1950 was due to settlement of dam. * Estimated or assumed. scs scs scs scs scs scs scs — scs ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS HADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RLSERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL ! NET DATE OF SURVEY PERIOD BETVEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG- ANN. BIFU)* (ACB&fT pa Aawn SPECIFIC •EIGHT DBV) La PER =U. FT.) . — ^ — AVG.ANM. ACaMULATDN PSBSQ. MU OF NET ML AkEA POt PESiaU iftirt* AC.-FT. | TOWS AO0CT SOPPLYBW DATA CO to RIT1S BASH (EOOOUfiA TO ABOVE BLAIfi) JAMES AH) BIG SIOUX SITO BASIMS (C _,_1 - 36-16 , — 37-lm 37-3 37-7 37-9 do . (to *- * " . , ™ *h*r*wil'rt !_.t ID do 7li*^tHild L4t-«n«I . 00 ™ * J da (tir-tjJi da Bartlott T9*Ktt*m »* 1 Ci-wh Liki HltclMll * * rtn 1°_ C™^ Sola [fe» ^ 5 tt (V«^ 3COlt »0. - 00 i ?° r? LUn S*.*llllon *n»LJLiloo it TiHh f Vm-^n 1 •(•lllljri ••l-rshod BO. . u * on d° ** sr~™~ *r " 0 . rs ^^ * °° *^ " «^- "*" "* Elklns Stock Pond »o. 1 Br. of Pro*an»i Cr^k ** 7° ClilnB Stock Pond Pk>. 2 co L*nd Otill»«tion Project Trtb. of S*d Ri¥«r Ho. 226-1. f° Pm< Ti^h ^r in Ho. 226-2. •_! B D Ho. 226-4. °^ Prr. TiHh «M *^ Ho. 226-«. Land Otlli»atlon Project Trib. of Bad Ri.T«r No. 226-13. Ho. 226-21. Land OtlllMtion Projact Trlb. o' Bad Rl»er •o. ^26-22. • -M^J do 250 do do ore do ^^ do ' " ^^ F 11 S Dak 1 « * ftwit S Dak LO2 1 r^*** " " WJ--7 ^^ ' " * ° S Dak 8^ do * MISSOURI RITES BASIN (ABOVE PIERRE Nlobrara and White Hirer B* Hay**, S. Dak. .58 0 rto . }) Pi«rr«, 3. Dak. .203 J 110 ^_ T do .166 tlo . 514 do 234 089 .«r# ' * 16 27 73 * TO MKBRARA 3i/ia .57 .197 .163 .511 Ma x»l7 Mar" ) *y Mu-. Oct. Jul) MOV. .I'llT 19W 19^ 1936 •1897 1963 1907 1936 1936 1945 1936 1945 * 8.7 8.7 7.*6 5,183 18.61 16.7 9.1 8.3 9.2 8.3 .909 2.234 2.198 6.84 ~ _ — ••* •6.7 9 26 •65 51.8 _ — 7 65 " .87 .26 1.785 .378 .16 .822 .458 .539 .285 .521 1.389 .200 • 492 368 2,527 426 144 — — •fcj S3 9CS nret sea scs 3C3 SCS acs 3C3 SCS 9CS SCS SCS 3CS ------- BBBfiB 98898888888 I II II II II II II II II M M I l§IRl§ I* IS R 8 S 1 8 C igishgsgiggm SSS85 I I I I I I I ~ I I I I till! I II II II II II M II M II II I If If If If IS 3 8 SSS R3 3 I 'I '\J~ 'I-- I 'UJJJJ I I IR IR i RPS : §S N CM N (V vfl (V c% •OO OOOOO OOOOO OOOOO I » I R I •s-ij I '*' I S I "'^'-J-'- | -rt--!- | Jrt-jJ^ | P. i li II !* !«' !J ii Is II II Ijrs'w'iissll |. £ £ k « ^ Sg ^ E S * S M I ~ I 2 I 3 t I I I I I rf ! I g I I I I I I Mill I I I I 3 SJ S P S S S 3 C R I I I I I I 131 l~ I S I S. I I M I" M8 I Mill Mill M I I IS I |U I I !H i i I ! I I I I I | I a f I l| i j ij m II 11 11 h I li nil} *« !l g i * I I I I ajiM i\a\ i « I 5 - INI tlti'iliti it '. 4 °. * °. « I i? if i T «t3t*Mi f «.t * i ^ 11 f' ^ -^ T1 1 -d I* •*! t Is I? ! MS le sill 1 3 1 J ~ 1' S i t t 2oSE55'33p j,5-i CJ I --HsH^^flpK t'ac fee ^ s3j*f;3^!l-3o'!ld'sj*iM "'It * *i^ * 3 a 2 ISji ^J |sJ o=!j!|sj. \s i s |" K 1 M "i*il illl li'ii'ir* -liSllJljIiiJiiJliJlilSlllilil JinsiiiiiiJiiliiiir MlS * f K fc R R F-33 ------- SUMMARY OF RESERVOIR SEDMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA DATE OF (SQUARE TOTAL MILES) ! SURVEY ! i NET I PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) 1 CAPACITY AVG.ANN. INFIOI RATIO (ACRE-FT PER ACRE-FT) iPEdFIC (EIGHT (DRY) LB. PER CU. FT) AVG. ANN. SEDBfiVT ACCUMULATION PEBSQ. m- OF NET DR. ARIA FOB P. >K)D SBOWN "AC~.-FT. | TOMS AcncY SUPPLYING DATA I CO 39-1 39-2. 39-3 39-1 39-5 39-4 39-7 39-8 40-1 40-2 41-1 41-2. 41-3 MISSOURI HIVES BASIN (HOBHIDGE TC ABOVE prERRE) h«r«nn* and Bella Fourche Siver Basins (Continued) 42-2 12-3 S*v Dtyta-HDod .UwnTolr— - Pr«d«rick Stock Dv* do KanMaeh Rasa-Tolr -itt ""do Col* Ra^ervoii • Battle Creak Detention Dta lellou Haiei *> *> *J ind^rvon RtMi-volr IjuVV Ifclstoo ° TO do ^^rtn "do -do Mew Undarwod, 3. Dak. MISSOURI RIVER Horwu, Grand, Ctnnonb*!: LjUBC(^"eQil n do' --- - - Hiddanmod Cn* S«lby. S. D«Jt. .40,. , . . .... -i-5 161.8 803 724 471 75 338 _ SCS 183 — SCS 33 — SCS 166 — SCS 1.74 1,478 1.21 1,553 2.08 1,288 .188 .403 28*. 7 614 ------- UPPKt TELLOUSTGKE RIVES BaSIH CO Ol 43-lb 43-2 43-3 43-4 43-5 43-6 43-7 44-U 44-2 44-3 44-4 44-5 44-6 44-7 44-» 44-9 44-10 Buf'alo Blll- E«d Spires- Lake Boonerllle Lake Fort Sent* Luke Bailey- Charleston Lake- Slji Mile Creek Mo. 2— Sli Mile Creek Ho. do do Sli Mile Creek Ho. i' Conservation pool capacity. Reservoir has greater capacity at ! 2/ Includes 0.03 ac.-ft. above crest deposits. I/ 1937-1955-39,097 eq. lai.; 1956-1961-34,692 eq. mi. lj Suspended - lend inflow was 608 ae.-ft.; supsended - load outflc p-rtod. Deposits too small to Measure by range surrey. v* Trlb. of rme«rudle CI-M* Orahaa Draw — do dn . do Rock Uaterhale Cr*»* do Trlb. of Petit J«*n CrMk- Jaek and Jones Cr-sekn Wiito Hirer-- •- Poorche La Pave Hirer Arkansas River Trlb. 3ha C 0ek . do do Trlb. of Hurricane Creek — do do fin ° j -oa aa Morland, **y. ~_ * u_ AUUUiSAS RIVER BA3I1 (VAN •on**/, vx. Booaerllle, Ark. Hoantainburg. Ark.— r **H» ™* Brmn rfa Horfork, Ark.-- Paris, Apk. Charleston, Ark. * rf- rf do Peter Fender, Ark. ~° .942 27.4 .81 .38 5.24 7,700 .918 27.4 .81 .38 5.20 7,670 BUSf.ll TO LITTLE BOCI) VH: 4.16 4.11 2.60 65 15.2 4,610 680 1,806 10.90 1.03 5.38 1.90 4.16 2.57 64 15 4,606 652 1,772 10.66 .93 5.26 1.81 3.91 Oct. 1954 Oct. 1955 Oct. 1958 Oct. 1961 Oct. 1954 Oct. 1958 Hov. I960 June 1949 Nov. 1949 Hay 1952 Oct. 1955 Oct. 1957 Oct. 1960 July 1948 •or. 1949 Hay 1952 Oct. 1955 Oct. 1957 Oct. 1960 Oct. 1954 Oct. 1955 Oct. 1958 Oct. 1961 Oct. 1951 Aug. 1964 tTE HITCB BaSM June 1935 HOT. 1935 Hov. 1946 Mar. 1929 «ov. 1935 Peb. 1936 Apr. 1940 S«pt. 1937 May 1940 Mar. 1913 Aug. 1935 May 1942 Apr. 1950 June 1943 May 1950 May 1938 Dec. 1953 Apr. 1937 Dec. 1953 Oct. 1954 July 1961 Oct. 1954 July 1961 Dec. 1954 July 1961 Dec. 1954 July 1961 July 1955 July 1961 July 1955 July 1961 31.7 17.0 1 3 3 4 2 .42 2.54 3.42 2.00 3.00 1.25 2.54 3.42 2.00 3.00 1 3 3 12.8 0.4 11.0 6.75 4.2 2.7 22.4 7.9 1.9 i 15.5 16.66 6.67 6.67 6.63 6.63 6.00 6.00 455,838 439,851 421,333 99.2 98.1 96.0 93.2 90.2 87.7 83.3 12.30 11.73 11. ca 10.83 10.61 10.58 3.13 2.94 2.54 2.62 2.59 2.47 193.4 191.3 176.1 154.5 819,132 802,004 494 490 481 289 282 •13,810 13,727 629 602 43,980 23,714 336,000 i/336,000 1,560,500 A, 560, 500 2,206 2,141 325 264 6/1,613.93 6/1,608.15 1/221.96 7/215.77 6/989.25 i/983.27 2/75.92 2/70.64 .492 .474 .455 3.906 3.862 3.780 3.669 1.797 1.747 1.659 4.241 4.045 3.797 3.734 3.659 3.648 3.817 3.585 3.098 3.195 3.159 3.012 1.098 1.086 1.000 .877 .625 .612 .130 .127 .532 .532 1.138 1.138 «.298 •.290 •.455 *.370 .469 .467 .090 .087 .708 .703 .183 .177 .372 .369 .029 .027 .34 .62 1.2 .8 1.0 .02 .08 1.68 .35 .06 .14 .01 .39 .42 0 .05 .11 .40 .98 1.38 2.43 .20 .455 .31 .66 .196 - V- .39 3.94 6/.17 I/. 21* 6/.S3 I/. 51 6/.26 2/.23 307 SCS CK cz SCS SCS SCS ipillway crest elevation. pw was 200 ac.-ft. during$j Sediaent inflow volune was computed to be 2,350 ac.-ft.; Much of this probably settled out over a large area in deposits too thin to be Measured accurately by echo sounders. 6/ Both sedinent and flood pools. 2/ Sediment pool only. * Estljiated or assivsed. ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE ffl THE UNITED STATES THROUGH 1970 hrj oo DATA SHEET NUMBER i RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA i (SQUARE TOTAL MILES) NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG ANN INFLOW (ACRE-FT PEB SPECIFIC *EIGHT (DRY) LB. PER CU. FT.) AVG. \NN SEDIMENT ACCUMULATION PEBSQ ML OF NET DH. AREA FOB PERIOD SHOWN AC.-FT | TONS AGENCY SUPPLYOK DATA ARKANSAS RIV5K BASIN (vAN BURQI IT, LITT.S ROCK) WHITE RIVER BA3TN ( 44-r< 45-1 45-2 45-3 4"i-4b 45-S 45-6 45-P 45-9 4S-1C 45-11 45-12 4^13 4S-15 45-r7 45-18 45-19 45-20 45-a 45-22 45-23 45-24 45-25 45-26 Dardanelle Reservoir do f .-do ,1o Like McAl eater 3° do- Pretty Water Lake Greenleif Lake do Kirk Lake Lowell Neosho County State Lake (Lake McKinley). ^" — - do State Fish Hatchery Lake do do WutAiktt Lake- - lo Wetumka "ity Lake do 3 e voy — Arkansas River do . Trib. of Illino e er -10,, Wilson -rente Ei do hi " air Paa.eab.Lc urcofc do Bull Creex n° • do 'P do do Fourche Maline Creek do Big Greenleaf Creek— nnamc Sprg. 3. * Shoal Creek Smll Trib. of Neosho River Dog Creek • . - par a rcc Pr^ C . r/ui-3 ice A Trib. of Pryor Creek " C° 5 Ine '"- ~oon r. o p ing Salt Creek . do- N. Caney River Big Caney River Dardanelle, Ark. 1/1 do do—- ARKANSAS RIVER Grand, Verdigris, at do do 0 do 0 ° ~ Wilburton, Okla. do do Sapulpa, Okla. Muakogee, Okla. do Baxter Spring?, Kana.- Parsons, Kans. do Claremire, Okla. ins Okl Wetumka, Okla. Sedan, Kans. Cedar Vale, Kans. do 3,703 BASIN (TULSA 4.06 2.35 8.72 20.9 30.7 40.1 21.2 2.3 19.8 fi.95 2.43 81. -5 2.41 2,210.0 3.38 56. 4A 400.0 .28 1.21 3.07 16.27 4.15 -33 .16 11,333 4.07 TO VAN BU dian Ri»*r 3.92 2.30 S.57 19.9 28.2 39.2 18.9 2.2 4.29 19.7 8.30 2.40 79.84 2.36 2,208.6 3.24 55-70 397.2 .27 1.20 3.04 15.72 3.88 .33 .16 Oct. 1964 Oct. 1965 Apr. 1968 Oct. 1954 May 1964 Oct. 19"0 REX) Basins July 1937 Aug. 1947 Oct. 1930 June 1940 1913 Dec. 1935 Hay' 1943 July 1952 Apr. 1963 1919 Sept. 1941 1928 Apr. 1950 Aug. 193737 Mar. 1957 1937 Sept. 1947 1936 Apr. 1950 1933 July 1947 June 1931 Apr. 1950 Mar. 1936 Dec. 1946 Mar. 1937 Mov. 1941 1R97 Sept. 1939 Mar. 1905 Aug. 1939 July 1927 Aug. 1939 May 1931 Oct. 1939 Apr. 1924 July 1935 1923 1934 1939 1931 1939 uly 1925 pr. 1945 eb. 1954 an. 1931 eb. 1954 Mar. 1953 Sept. 1960 Jan. 1938 Sept. 1960 1.08 2.^ 9.58 6.42 10.1 9. "5 22.5 11.0 9.2 10.75 22 22 12.3 9.2 10 14 14 n.e 10.75 4.7 42 34.4 12.1 8.4 11 16 5 8 19.6 8.0 23.2 '.5 22.7 4oO,3OO ,52,hOO 443,500 1,304.03 1,275.62 1, 253.26 1,260 1,249 522 517 1,094 911 4,995 4,660 4,525 18,397 17,509 10,355 9,896 3722,600 24,468 i/23,816 23,429 2/22,327 580 574 2,341 2,158 6/570 511 9,844 9,030 344 322 13,005 12,828 111 69 10,4O4 7,580 680 651 4,258 3,909 31,686 30,509 28 26.5 34.0 32.9 123 U1.9 2/4,961 4,489 4,357 2,076 1,898 20.9 20.2 22.8 a. 2 2/.0532 2/.0532 1/.0540 .446 .436 .429 - .640 .597 .580 - - __ - - 1.02ft .930 .903 1.341 1.226 " *80 80 68.8 76.1 54.2 94.72 94.72 - 48.10 •60 »60 51.17 - 55 60 C.o26 .321 .73 .86 .278 .23 .949 .732 1.83 .63 1.43 .532 2.8 2.7 .29 3.05 .21 .85 .47 .43 .04 .74 .749 .269 .35 .18 .46 1.51 8/1.05 1.98 .44 1,090 560 1,093 1,425 2,160 743 5.776 5,339 - 450 52.3 967 574 •x SCS scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs scs ------- T1 co -q 45-28.1 45-29 45-30 45-31 45-32 45-33 45-34 45-35 45-37 45-38 45-39 45-40 45-41 45-42 45-43 45-44 45-45 45-46 45-47 45-48 45-49 45-50 45-51 45-52 45-53 45-54 45-55 46-lb F p ... **trto Double CreeJc Sit* No. 5 (1 "" r T t° Ink "iVOIido _ _ , T>v Hound Valley Experimental Sta. 0 -*«. 0 *r „ p° ono Cane Creek Site No. 11 Big Wewoka Site No. 17 . -" * *^ , raddle -*noy HlTer " Ri mn ' r do rfn ^^ ^ C* * 7° anadlan Trib. Neoaho River Trib. of Pumpkin Creek Trib. Verdigris River K Trib. o o „ * 7° Trib Duck C ok * r° rtn d ri rtn 7° Cans Creek Big Wewoka ° , Dunlap. Sans. 3od*Ij Ifiin ^K^» ^U11* llnrtfl Kan UI' do°n' ^U1I>" p .odarvalo, Kana. u i w ni.i Ao^*~ Hamona, utL*. ~° irk ron. ** "*rto* *^*- t Ban Toronto, rn. Wiitefield, Okla. do °n* Hound Valley. Kana. Edna _^do ^Lr"*t' '*QD- K«n d * * ™° La Fontaine, Eana. °° do Lonirto Kan Lonffton, nano. Burlln.rto Ka ington, no. ^°^ HoldcmoJ.!!), Ukla. Olomilgee. Okla. Wowoka, Okla. ARKANSAS RIVER Middle Canadian, Lower ° dQPI^* ^t^°" A 2.25 .25 .194 15.9 .2 .345 .49 732 2.39 7.65 10.16 123 730 47,522 .19 .42 .22 .23 .20 .38 1.75 .13 .23 .41 .25 2.26 8.96 2.16 BASIK (GARDEN Cljaarron, and 1,735 2.25 .25 .192 15.3 .2 .345 .49 712 2.36 7.58 10.06 117 714 13,693 .18 .42 .22 .23 .19 .37 1.73 .13 .23 .40 .25 2.20 8.89 2.11 cm TO HJLS, Salt Fork Ri' 1,485 Sapt. I960 Jan. 1951 Aug. 1960 Sapt. 1936 Sapt. 1960 Jan. 1939 J«l7 1957 Dae. 1936 Apr. 1954 1920 S«pt. 1960 Jan. 1938 Jul7 1957 Jan. 1943 Sapt. 1960 Fab. 1950 Jtna 1958 Feb. 1955 Apr. 1964 Sapt. 1969 Hal-. 1943 Oet. 1961 Sapt. 1936 Sapt. 1965 Bar. 1950 Dae. 1959 Mar. I960 *7 1966 Fab. 1964 June 1969 Oct. 1939 Aug. 1967 Jnna 1954 June 1968 •OY. 1953 June 1968 Dae. 1956 June 1968 Aug. 1967 Aug. 1967 — 1933 Jul7 1967 Jul7 1937 J«l7 1967 June 1937 Jul7 1967 Oct. 1948 Aug. 1967 — 1939 Aug. 1967 June 1960 Aug. 1969 HOY. 1965 Sapt. 1969 Har. 1963 Sept. 1968 O rer Basins Jan. 1943 June 1949 June 1958 TW 1 Q60 26 9.5 24 18.5 18.3 40 19.5 17.7 8.4 9.2 5.5 18.58 28.9 9.8 6.21 1.33 28 14 14.6 11.8 33 40 34 30 30 19 28 9.1 3.85 5.53 6.42 9,0 48.5 484 477.8 10.66 9.26 10.59 8.56 6,491 5,935 23.9 21.6 54.97 44.12 81.46 77.94 295,130 292,565 747.36 734.29 730.53 361.44 325.78 771.0 604.7 59,650 57,270 195,300 192,060 3,848,000 3,798,400 4.74 3.54 6.90 4.77 5.01 3.92 12.0 11.1 24.41 20.1 15.37 8.72 53.04 29.69 3.8 3.0 5.3 4.5 16.38 15.0 8.09 4.17 690.3 679.0 2,983.6 2,954.7 691.3 680.7 107,340 106,150 101,750 L - •1.591 •1.455 - 1.109 1.099 .83 .81 .81 .059 .053 .316 .248 1.447 1.389 .559 .550 .89 .88 .07 .05 .032 .022 .044 .034 .10 .093 .33 .27 .110 .062 .080 .045 .080 .062 .062 .052 .n .098 .09 .045 .95 .94 .96 .95 1.36 1.34 1.27 1.26 1.21 1 .fA SO 55 60 •60 70 57 60 44.2 54.3 54.3 •60 77.23 50.4 62.2 •60 •60 •60 •60 •60 •60 •60 •60 •60 •60 •60 62 55 60 57.8 67.0 ft1;.-* .45 .29 .23 J/.60 1.99 .28 1.61 .41 .429 .60 .29 .25 .57 2.08 .731 .68 .24 .36 .32 .35 .68 .46 .40 .23 .13 .18 .56 .56 .85 .91 .125 .329 .ttil 490 347 300 J/S10.2 2,236 427 1.9W.8 536 413 710 343 745 3,499 802 921 314 470 418 457 888 601 522 300 170 235 731 762 1,018 1,189 157 498 74 SCS aa aa 03 scs scs scs a scs scs scs a a a scs scs scs scs scs scs scs scs scs scs scs scs scs scs ex I/ 22,241 sq. ni. is probably noneontrlbuting. 2/ Based on inflow from net sediment contributing area. 2/ Original topo-rraphic survey. i/ Prom "A" reconnaissance investigation, Shawnee Lake, by Victor H. Jones, Geologist, SGS. %/ Present ac.-ft. as showi by the two surveys. 6/ Lake drained and dam raiaed 1937. Original capacity at 1938 crest. I/ Dam raised 11 feet Mar. 1946; all values based on prevent elevation. 8/ Dan broke Apr. 1945; rebuilt Mar. 1946; this period not included. 2/ Includes 0.03 ac.-ft. above crest deposits. * Estimated or assumed. ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W THE UNITED STATES THROUGH 197C CO DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL | NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG ANN BATO (ACRE-FT PER ACRE-FT) SPECIFIC (EIGHT (DRY) T.B. PER CU. FT) AVG. ANN SEDMENT ACCUMULATION PEBSQ ML OF NET DR- AMA FOR PERIOD SHOWN AC.-FT. TONS AGENCY SUPPLYING DATA [ BASDJ {OAHDEN CITY TC TULSjO •ron, and 5»lt Fork River Basira Continued) ,^. 46-7 fc*-8 46- 9 46-10 46-11 46-12* 46-1 46-17 46-25 46-26 46-?7 46-28 46-29 46-30 46-n 'Veat Salt Plain* 3*it PV. oT Arkansas rllvsr do do ^° at ]u- *° (Lake L»rrmb»»). I*°~ „ , i-d« "rrih do. , do — Suita F« Indiana!* Cr**k Outhrie- . Trib. of Cc-ttonwood Cr*«fc- «!„.. «x* F«d lioi.JUr.Cr~ H*rrlB Stock hand do Lak.Eldor.do - - ^tchel Cr«k Lake Pry«r- — — tolf Cr**k dC- , ~ , M, _ . ,io do do oo *o. 2. ^°~ r _k. ' 1 d° UmaMxl " C3 1 - " ^r- LongUm- *> — ^° \ • -.™a. ci rj «lty Lake-- • -ow ""** °~ „ ... ^° Trtb f So Ganadi R, 0, r . ^iott . ondn Tri _ . r ^. m/mui IM? P Trfh f Rrlrl nt* rcr« Hill Pond rrt -^ r unag ^ SI Cr**k Nichlaua- Trib. Jl^uji 1 e«U 110 T-lh SI " ak e^__ " do_ Koulouris Trib. Sand Creek trtj.— . Trib. Bluff :r*ek 5«ith - Case "rib. Little Ark. River Uorkmri Trib. Medicine Lodi?e River ^n^ 1^0 Barrett - - «1H >•* ' 1°~ °~' XUlei (MI r r Jet, Okla. 1 if d MH.) r ' Au«urta, Uno. - Gwthrle, Okla.——- ^"T"- <«--— - dT Eldor.*-, fan,.- - fir1 n fio * * " . -_ st m in d* r" *' ^Imrron, Kan». Andal T nruii ^, r ' Wellin^to K do Newton, Kana. Little BiY«r, Kans. Medicine Lodge, Karn.- Anthony , Kans. 3,200 13.30 .31 35.1 108 , _ 3.36 .55 .24 .24 .56 .59 .30 .34 .67 1 20 3,156 1.84 12.95 .31 34.3 108 3.36 .54 .63 .526 .24 .23 .56 .59 .30 .34 1.20 Juno Doc. Apr. Oct. Oct. Oct. Apr. Apr. Sfipt. S-pt. June July Aug. Oct. Sept. 3«pi. Dec. June Aug. Mar. June Aug. Spring July Aug. July 1941 1949 1929 194O 1937 1920 1935 1939 1940 1940 1928 1937 1939 1947 1953 1959 1966 I960 1942 1956 1935 1955 1955 1955 1949 1941 1943 19.32 1967 1958 1967 1948 1968 196S 1958 1936 1968 1955 1968 1956 1968 19S7 196B 1959 1968 8.5 11.4 H.2 8.6 14.5 1.0 2.5 9 7.4 5.83 6.42 6.92 11.40 14 20 13 17.9 14 11.8 35 9 19.92 33.92 32.17 13.42 12.1? 9 .i 08 ,000 292,000 2,fll2 2,641 33 819 365 295 1,595 3,064 2,608 3.74 3.43 12.37 3,213 3,082 A44 717 385,900 2,945.06 Si/56 20.44 9.62 50.28 2/8.50 4,371 3,986 14.87 8.97 ?6.3 30.7 13.38 6.43 46.14 5/13.6 4.O9 3.38 9.64 6.95 5.76 66. 89 62.29 10,0 1.79 25.26 20.29 26.73 21.91 39.92 32.24 6.08 2.87 1.067 1.011 — — — .316 2.10 2.CT7 2.06 1.391 1.283 — 1.311 1.196 .085 .067 .147 071 .15 .04 -It .13 .158 .24 1.86 1.73 .18 .03 .87 .70 .81 .66 .59 .47 .0^8 .013 48. b 58.9 *60 69.47 •60 98.52 58.1 •60 •65 •65 66 " . TO. 9 50.2 5^.1 95.66 •60 94.89 85.7 72. O*7 83.5 103.4 — fc5.4 — — . TO -(SO "60 '6C •60 *60 •60 *60 •60 — "60 0.586 1.93 2.68 .459 3.40 .45 2.42 1.0 .495 .426 .16 .30? .063 1.92 2.61 — 2/.2P .0*7 .32 1.33 — yi.o — .2' — 1.12 — .22 — .57 .58 1.00 .84 .44 1.23 1.1S 1.01 — .30 62O 2.522 4,055 600 7,296 569 3,162 1,416 701 612 _ 4,6^4 65.3 76.4 4.0O0.27 3,410.75 — i/578.68 134 — •^12 — 2,419 — V2,?52 313 — — — 335 — 745 75« 1,307 1,098 575 1,607 1.542 1,320 — 392 OS sns scs scs scs scs ZK sea scs scs scs scs scs scs scs xs xs scs scs ------- to CO 46-33 46-34 46-35 46-36 46-37 46-38 46-39 46-40 46-41 46-42 46-43 46-44 46-45 46-46 46-47 46-48 46-49 46-50 46-51 46-52 46-53 46-54 He^B^ Pond 0*1-^*^ FW.J ~° lebcrt do rt D«Tl ° Trtt bcboo Pond 0 Harbor „ ?° or~' " n_ i u*lth rona . ^^*^ den ^ CO. Conchas Reservoir rt^ do A ° oo n ttoocrroir »o. ~ do ''^ *" Ui Reservoir No. 11 Eleservoir Ho. 1? — Kcucrvoir o. 1J noacrvoir "o. 14 e _, -BlU Trib. Kedicine Lodge Hiver Ti-ib Pn B.1 Trll*. IXtnOO HiTBr Trib. ¥et Walnut Cre«* Trib. BU Sandy- do rt H«^kti* Ci-Mlr ..Q* ^reak *"Q*eL " rtn Trib. Ark. River Trib. Buffalo Creek — *_«v * Bj . awnoo Trih SLat C ok F0 rto 3trinjj Ci-««k ^^*i r»«* Trib. Little Sandj Creek— ,,, Jw ^ ,, t r "il* -^frroj m rf ' «rt: TIIL. lurr ur Canadian and Conchas do 7° rt do . , ° , ^ j ° do — do 0 A ° • Hadlcine Lodge, K&na.- Jet«i Kan • ^ma' Dighton, Eana. rt * ' d ~° H fianlEnd, tana. Kal *ta Kan * r v - ° 1 rt Little Siv«r, Sans. Ba «1 Kan ^l*fcj*p* THohtn° Kan nffi . i , dT' n ' fiuah Cimt Kan T™ * ' aaft3- Con S™H S« 'd ** *B;'' ^ *" San ™~* mna" — ^> ^° J j J"13" ohlond, tana. AHKAN3AS RIVEE U^per Ciaarron ai Conches Da*, X. Hex.— ~° d T° j ^° 0 do do J° '° 0 0 Liberal, Kans 1.73 3.0 3.e .23 1.07 7.57 1.98 2.40 1.83 1.20 1.01* .57 2.1 .30 1.63 .56 .31 2.17 .95 .82 2.13 BASIS tLAHAE Tn Id Upper "jnafHA 7,409 - _ .36 1.71 3.0 2.2 .23 .90 4.75 1.97 2.37 1.82 1.20 1.07 .57 2.1 .30 1.61 .56 .31 2.0 .93 .52 2.17 GA1DEN n Blysr ' 6,976 - - - .36 Sept. Feb. Aug. Har. Aug. Aug. Aug. Jan. June *W June Oct. June »>r Julj Jan. Sept. Dec. Aug. July Aug. Aug. Aug. June June Aug. Aug. Dec. Aug. Oct. «ug. Aug. Aug. June Julj No-r. July Juni July JulJ 3ITY' BasljiB Maj June Oct. Feb. Oct. Oct. - Mar. 1963 1%1 1968 1952 1967 1940 1967 1952 1966 1961 1966 1962 1966 1947 1966 1951 1967 1952 1967 1956 1967 1949 1968 1962 1968 1946 1967 1951 1967 1958 1967 1949 1967 1956 1967 1951 1966 1956 1966 1952 1966 1954 1966 1939 1940 1942 1942 1944 1949 1963 1970 1912 1946 1912 1946 1912 1946 1912 1946 1912 1946 1912 1946 1962 1QA* 18.12 7.5 15.5 27 14.5 5.2 3.7 19.2 16.75 14.75 11.13 19 6.2 21 15.75 8.8 18 11 15.1 7.75 14.5 12 1.4 2,1 ll? 4.3 14.7 6.92 34 34 34 34 34 34 47-2 47-3 47-4 47-5 47-6 i.7-7 47-S I/ Excludes 4,642 sq. mi. of watershed not contributed to runoff, 1,735 »q. nd. above Port Supply Dam, and 25 sq. mi, surface area of Canton Reservoir, 2/ Includes 2.33 ae.-ft. above crest deposits. JJ/ Water supply pool capacity. Reservoir has greater capacity at spillway crest elevation. 4/ Includes 0.39 ac.-ft. abov* crest deposits. 5/ Spillway eroded 2 ft. o/ Capacity based on surface area x 1/3 deepest fill. If During the period 1^12-46, a total of 2,435-ac.-ft. capacity was added by reservoir enlargement. 8/ During the period 1912-4r>, a total of 126-ac.-ft. capacity was added by reservoir enlargaMnt. 2/ Dorijig the period 1912-46, a total of 6?2-ac.-ft. capacity was added by reservoir enlargement. 10/ During the period 1912-46, a total of 490-ac.-ft. capacity was added by reservoir enlargement. ll/ During the o«riod 1912-46, a total of 264-ac.-ft. capacity was added by reservoir enlargenent. * Estia-ateri or assumed. ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W THE UNITED STATES THROUGH WTO DATA SHEET NUMBER — 1 ' ] RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL NET , 1 DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVa ANN. INFLOW RATIO (ACBE^T. PER ACRE-FT) SPECIFIC (EIGHT (DRY) LB. PER CU. FT.) AVG. ANN jxuimm ACCUMULATHN potso. m. OFNCTDB. AREA FOB PQUODSBOW AC.-FT TONS AGncv SUPPLfWG DATA ^ o 47-9 47-10 47-11 47-12 47-13 47-14 4S-2 48-3 48-4 48-5 4S-6 48-7 48-8 48-9 49- la 49-21 49-3 40-4 49-5 40-6 ARKANSAS RIVER BAS1X (LAKAR TO GARDEN J1TT) "regory - L*h«y — Hart shorn A/wrine ik; John H>rt In R*aerroir 'ror-wrly Caddoa Rea. ProJ.). £ --do • - . do -Ju Qrowi Reservoir Ho. 1 Moddy Greek 3-1 3i« Sandy Creek iVqterflhed — 4 __ — do — 1o Jenkins Pond 'xj-don :"unt,ry :iub Lake -\-j Trib. *rk. River Trib. Cimrron Trib. Little Bear Creek— Trib. Cimn-en do (to * :mirl«7 ArkarMs River to rfn to Vin Brewer Arroyo- Muddy Creek. Johnny Creek- 40 TUrlt*5n -Jo Bl* 5andy Creek Rio Chana do Kins -ra»K Trlb. of Lewi* Creek (JO •••• •• 1 U Qj Upper dafti-ron and Upper ! !*OSC^-_^B1 Syraauae, Kan a. 4a-_ * do 6.5 2.78 1.90 1.06 .47 3.42 8.91 RIO ORA1BB BASIN (ABOVE B5PANOLA) Harty, Colo.- 1/11.715 do Trinidad, Colo. Caddoa, Colo. fto *, . Peyton, Colo. Abiqnio, H. Hex. 2 Fowler, Colo. RED RIVER B^SLN Little and do °_ Mansfield, U. Paris, Tax.— " VI1 LA do - - 74.6 154.2 52.01 78.8 608 " 5.4 ,146 13.48 (DEHISOK Sulphur 51.6 10.4 .35 1.41 683 Rivar Baaina 6.5 2.75 1.89 1.06 .46 3.40 8.91 AND ARKANSAS 18,102 - 74.4 152.4 47.44 78.5 606 5.3 2,127 13.34 TO GRAND SCOR Rivar Baaljis 49.6 1.26 10.3 .32 1.30 613 (Contlm Apr. Juna Oct. Juna Mar. Juna Juna Juna •»«. Jane Oar. Juna *pr. Juna RIVHi U Apr. July Dae. S*A. Oct. *UJ. Har. Sapt. Au,. Nor. Fan Dae. HOT. Apr. Har. Fab. July Apr. Oct. Har. B! Fab. Tkr. July Har. July Har. July Sapt. Juna Nov. "ay lad.) 1951 1967 1960 1966 1950 1966 1961 196t 1961 1966 1953 1966 1951 1967 IS III 1942 1942 1943 1944 1948 1951 1957 1962 1966 1968 1900 1939 1919 1939 1900 1940 1911 1940 1912 1937 1939 1962 1965 1963 1967 1908 1968 1923 1936 1956 1900 1936 1956 1931 1941 1925 1954 1898 1959 1949 1961 16.5 5.7 16.2', 5 4.8 13.3 16.5 0.3 1.4 0.7 3.7 3.4 5.7 4.6 4.5 1.9 39.4 28.9 25 2 3 4.58 60 13.1 19.7 36 20.3 10.3 29 61.0 11.5 62.2 50.83 Ij5.6 133.8 14.6 8.75 4.5 3.75 31.8 31.2 128 119 92.7 78.2 — 701,775 690,345 688,5?) 683,257 675,097 662,870 645,512 642,390 631 ,121 618,668 758 82 16,918 15,287 36,203 30,738 4,005 2,463 38,274 25,020 23,040 326 302 579,039 572,695 563 527 11,487 10,755 9,964 6/1,394 1,324 1,285 181 128 157 150 558 430 967,900 967,900 1.79 1.50 4.6 4.5 .72 .43 .40 .33 6.4 6.2 3.5 3.3 1.97 1.65 .418 .391 .362 1.792 1.702 1.652 .561 .536 .742 .572 1.516 1.516 70 •50 •75 •75 65 •75 •TO 0.11 .11 .19 .U .28 .20 .10 — SCS 167 — SCS 1JD — SCS 310 — SCS 229 — SCS 396 — SCS 327 IK 2.43 2.43 2.41 2.38 2.34 2.28 2.26 2.22 2.18 — _ __ — ~ l.°0 1.76 •3.9 •3.7 •75.7 •75.7 •75.7 •75.7 •75.7 •75.7 •75.7 •75.7 •75.7 89.07 75.25 68.36 75.4 " •80 •75.7 — — .075 .443 .129 .210 .178 .0398 .147 .362 .233 .5J5 I/. 241 .680 .87 1.63 1.5 .65 V-045 — 124 no 213 346 29J 65.6 242 597 — 452 ST7 __ 4/1.515 _ 1,117 _ — — 2.613 1,072 — — 3CS 9CS 3C3 3CS 91 3CS OK SCS 36.4 31.5 68.6 33.14 1.13 .81 1.54 1.52 .50 .78 1.62 642 — SCS 1,043 — SCS — SCS 1,165 _ SCS 1,169 — d ------- 49-7. W-8 49-9 50-1 50-2 50-3 50-4 50-5 so- 6 50-7 50-9 50-10 50-llc 50-13 50-1 5a 50-16 50-17 50-18 50-19 50-21 50-22 50- J3 50-24a 50-25 & tola Lake Texarkana fin H T . Ai-Jj-ui-a Club Lake R-r» ^1 Bymr3 - L*ko f i artSj ^L^° J. J. Harrison Lake C. W. Lester Farm Pond Ho. 1- C. W, Lester Farm Pond Ho. 2- -anta Hona Lake nf Lake Duncan i? Like -ilnton OOllcTUO do Jj° T IT T (Q.WI D* 1 HUcc ToxoBtt tUeniasn Una; do A r+in PnnH bartHDur Pond r tutte SI Hn Cavalry Greek -Ate No. 1 ri° 0 Chigley Sandy Site ho. 5 dn ™ B -oit Pond No. 1 n D Dean Pond No, ^ n 0 Doan Pond No, - • • George Pond p Hal_ Pond Nc, 1 w t Harrison o. . „ i riaon No. ~ K ^-np " -In Hill ^reok No. 17 do Muncrlef Farm "ond — Drainage area adjusted to conform Off chainel -egervoir. Excludes wat^- and sediment divert Per 100 ac.-ft. of water diverted erroir between 191C and 1939. Sulphur liver — . 0 Crnroan Barn JW ^ J do 3uj.pimr r -iJdu Cro Mri =Tt 101 rto tu rn° f L. 3° ° r (in *ah*ta ttiV*r Trib. of Broken Leg Cre«k- Beaver Creek tr-t k- «k d Turk Cr t* TirKQy UTeefc rfe P lr LTay ^r00* h P L- D»H ortn or aod iu.vcr 0 BI lirer °° Trib. of Little Washita R. * 71 0 Chigley Sandy Jnna-nod „ H° ^^* "r«*k do do Unnamed rt ^° rt d aahita Trib. of Sandy Creek with 'J 5.G.S. publis^e-i drama ed from Arkansas River a.-.d Hor froni Ark. River and Horse Cr. Tejcarkana , Tex. do Shreveport, La. rtn Sulphur Springs, Tex.- RED RIVS ni»jrc, UKll. Bn Okl oya , u_jni I-»_T ' Lindsay, ukla. Cheyenne, Okla. do ern°d' ax ' C t OtLa anuto, UlciA. ~° """» ' H T on^3"1' "^^ ~° "hi Inaha , *. ^ rd 11 ° °ri«' ** do do Wynnewood, Okla do ~i j . 1^.1 Ilnton, UKla, ^hoycnno, Ulcln. rt Canadian, Tejc. odoy, UlLLa. f rt?° * 3 ° ° T yno , ex. Mill Creek, Okla. flo Wynnewood, Okla. ge irea. ae Creek. Total of 564.918 ac.-ft. 3,400 266 52.50 S BASIS {ABOVE 4.15 2.66 1.81 .88 2.04 .64 336 11.0 23.6 •1.5 2,515 39,719 .68 2.19 .81 .39 .0359 .164 .535 .20 .237 .292 2,099 1.61 .031 diverted 3,213 251 51.46 DENI50N'/ 3.91 2.55 1.7O .81 2.03 .63 334 10.4 23.1 l.U 2,104 28,925 .67 2.15 .79 .38 .0354 .161 .535 .20 .237 .292 2,067 1.58 .029 43-yr Sept. 1954 — 2,654,300 Aug. 1958 3.92 2,654,300 July 1970 12 2,654,300 Dec. 1946 — 96,100 Oct. 1951 4.8 9fa,100 Apr. 1961 9.5 96,100 Sept. 1962 9 2,787.9 June 1938 15.5 1,644 1904 — 507 1936 — 865 Hat. 1949 13 837 Feb. 1932 — 349 Ifer. 1950 18 282 — 1945 — 42.4 June 1949 4 22.8 June 1944 — 16.3 June 1949 5.0 13.1 Oct. 1929 — 15,755 Jan. 1948 18.2 11,5*8 Oct. 1937 — 6,291 Aug. 1950 12.8 5,783 June 1938 7.4 3,961 Nov. 1950 12.4 3,343 Kay 1938 50 85 June 1948 7.5 185,035 July 1953 5.1 178,610 Apr. 1967 13.8 168,117 Oct. 1948 0.2 5.718.COO June 1954 5.7 5,553,000 Mar. 1962 7.8 5,392,900 Sept. 1935 - 59.9 Maj 1955 19.7 41.8 July 1948 — 505.4 Sept. 1959 11.15 476,6 Aug. 1964 4.89 471.8 June 1969 4.85 458.8 June 1955 — 263.67 Aug. 1959 4.12 258.74 Oct. 1963 4.15 242.20 July 1957 10.28 21.53 Mar. 1955 11 .807 Spring 1941 — 15.8 ter. 1955 14 13.4 June 1952 — 15.197 Apr. 1958 5.796 13.463 May 1939 — 17.59 Aug. 1957 18.25 13.47 Apr. 1958 5.93 a. 706 Apr. 1958 6.59 14.242 Oct. 1922 — 560,000 Sept. 1958 36 461,757 Dec. 1948 — 498.45 July 1959 10.63 492.13 Aug. 1966 7.06 487. 11 Aug. 1935 — 8.710 Nov. 1957 22.22 7.968 Little deposition due to daai washout, period was about 0.063 ac.-rt./nu2-yr. Spillway crest was lowered 3 ft. in 1 Date of original survey for new dftffi o Estinated or assumed. .13 .13 .13 .405 .405 .405 .125 .100 — - — - - 1.74 1.61 .512 .357 3.05 2.87 2.84 2.77 1.410 1.384 1.327 .706 .591 .469 .J51 1.505 1.276 .407 .361 .239 .183 .594 .581 .419 .382 2.493 2.056 1.06 1.04 1.03 1930-47. True 932; capacitiea ver deposits pi* — - •85 40.7 ~ 63.4 63.3* 65.9 - 52.3 66.9 70.2 52.1 57.9 62.5 •75 74.5 74.5 60.3 60.3 61.49 91 88 70.95 •70.2 79.68 68.53 - — 1.53 2.52 1.16 1.26 4.59 2.41 1.02 .689 3.«2 2.54 2.23 .64 .495 .599 .361 .785 1.00 .709 1.37 1.20 .46 1.25 1.52 3.22 1.07 .69 1.06 .559 - 2,832 2,234 5,275 3,505 3,201 5*4 1.104 588 991 1,2*1 9*5 2,23» 1,94* 74* 1,993 1,996 4,229 1,433 1,368 2,032 863.82 1.15 1,758.30 .325 5*4.01 .733 1,094.06 1.32 - 70 .37 564 •75 .45 816 •60 1.15 1,502.82 aediJoent accuwlation rate f are based on present elevati iced behind old dan. CE a scs scs so scs scs scs scs scs scs scs scs EB a scs scs scs scs scs scs scs scs scs scs scs scs scs op ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS HADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER ! RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE TOTAL MILES) NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG. ANN PER SPECIFIC (EIGHT DRY) ILB. PER CU. FT.) SfnffiHT ACCUMULATION PEBSQ W- OFNETDR AREA FOB PEUODSMNN AC.-FT. | TONS AGEHCY SUPPLYING DATA HED RIYER BA3H (ABOVE DEKI30M) (Continuad) to 5O-29» 50-30b 50-31» 50-32b 50-36b 50-38 50-39 50-40 50-4lb 3.89 6.46 3.50 2.87 .171 .162 .205 8.18 — — — 5.22 _ — — — .61 — — — 3. 84 — — — 5.2* — — 3.46 _ — — 2.80 — __ — 1.00 — — — 11. 28 — — 5.11 — — 10.04 — — — — 2.20 — .171 .162 — .205 .60 — — — .95 — — — 1.73 — — Jan. A«e. Oct. *«,. "«I Apr. *7 Aug. July Apr. Oct. Oct. July MU-. July S«pt. July Apr. Oct. Sept. fer. Oct. Oct. 5«pt. Apr. Oct. S.pt. July Sept. »ay Aug. July Aug. July S^t. Aog. Dm. Oct. S.pt. Aug. Aug. Oct. Oct. Aug. June Aug. Oc'.. Oct. Sc.pt. Jan. Apr. Oct. Apr. D«c. Apr. Ju. S«pt. Aug. June Hay July Oct. July Mar. S«pt. Aug. 1957 I960 1961 1970 1951 1956 1960 1965 1970 1951 1956 1961 1966 1951 1957 1961 1966 1951 1962 1967 1951 1957 1962 1967 1951 1956 1961 1966 1951 I960 1965 1970 1952 1957 1961 1966 1951 1956 1961 1966 1951 1956 1960 !%•; 1970 1951 1957 1962 1967 1947 1958 1945 1958 1944 1958 1949 1959 1964 1969 1949 1959 1963 1968 1950 1960 1965 — 3.5! 4.14 5.81 — 4.96 4.06 5.02 4.92 — 5.47 5.00 4.80 — 6.39 4.19 4.81 — 11.53 4.96 — 6.5» 5.0 4.93 _» 5.50 4.90 4.80 — 3.68 5.25 4.98 — 4.92 4.2. 4.86 — 4.62 4.88 4.86 — 5.13 4.04 4.79 4.91 — 6.16 5.0 4.96 — 11.266 — 12.564 — 13.33 — 10.70 4.91 4.85 — 10.25 4.2> 4.82 — 10.50 4.95 2,401.1 2,303.3 2,277.3 2,213.1 1,591.29 1.453.69 1,380.47 1,344.75 1,338.82 157.68 148.40 139.98 125.60 1,273.21 1,217.58 1,152.23 1,127.06 1,956.05 1,813.2 1,806.22 1,275.09 1,217.59 1,178.72 1,175.25 1,046.02 1.01B.8 943.9 888.0 315.15 283.09 286.79 275.82 4,463.43 4,294.49 4,164.87 4,038.34 2,065.88 2,033.89 1,987.93 1,979.45 1,584.9 3,465.8 3,322.4 3,292.7 3,276.0 970.7 942.12 913.51 873.9 15.794 13.943 a. 035 16.627 7.353 6.673 223.4 207.7 199.6 179.9 242.4 236.2 233.8 229.3 587. 3P 566.24 548,66 2.72 2.61 2.58 2.51 4.67 4.26 4.05 3.94 3.93 4.38 4.12 3.89 3.4? 4.45 4.26 4.03 3.94 4.12 3.82 3.80 4.94 4.72 4.57 4.56 6.23 6.06 5.62 5.29 4.85 4.43 4.40 4.24 7.29 7.02 6.81 6.60 4.41 4.35 4.25 4.23 5.53 5.15 5.13 5.06 5.06 b.14 5.97 5.78 5.63 .329 .290 .438 .346 .197 .179 4.33 4.02 3.87 3.49 1.11 1.08 1.07 1.05 1.780 1.716 1.663 90 90 •91 — 61.49 83.11 83.11 •83 70.20 77.87 •77 — 95.7 — •80 70.7 •72 — 75.78 79.4 •SO — 79.3 82.8 •75 — 93.08 68.1 *75 — 77.94 74.85 •76 — 8O.6 79.79 •77 70.4 59 59 •60 81.53 79.4 •83 77.65 — 85.34 82.73 75.68 75.68 •75 61 61 •61 — 85 74 3.34 .77 1.24 — 5.31 3.16 1.36 .23 2.79 2.75 4.92 — 2.27 4.06 1.36 2.36 .27 _— 2.52 2.20 .20 — 1.77 5.46 4.16 1.12 .25 2. 20 — 3.04 2.73 2.31 — 1.30 1.84 .34 __ 2.31 3.53 .62 .34 2.08 2.W. 3.63 — .959 — 2.167 .249 2.45 2.75 6.77 .63 .60 .98 — 1.16 2.05 6,547 1,509 2,563 __ 7,111 6,263 2,462 360 „ 4,266 4,672 8,184 — 4,731 5,501 1,980 3,634 529 _ 4,160 4,148 436 __ 3,057 9,996 5,627 — 6,320 371 3,611 — 5,161 4,209 3,874 — 2,281 3,131 402 3,540 5,418 797 526 3,694 4,445 7,036 — 1,621.88 — 4,027.81 448.66 4,038.4 4,532.9 10,872 834.1 794.4 1,274.6 — 2,147 3,304 9C3 scs so; scs scs scs scs scs scs scs scs scs scs scs scs scs ------- *>• 00 50-4 5* 50-46 50-47« 5O-48 50-49 5O-5O 50- 5i 50-52 1-1 51-2 51-3 51-4 51-5 51-* 51-7 51-«b 51-9 51-10 5i-n 51-12 51-13 51-14 51-15 51-16a 51-17 51-18 51-19 51-20 ~ . - ^ Chigley Sandy Sit* Ko. 4 do Floo-1 H*t*rdirtg 3tmctor« Bo. 2 Su* O. Hftter*«J Rarnlt fc 1A . " 3ng»r Cr*** Site ft>. 13 Upp*r tbahlta River Sit* *2<- Kmt Cr** *.t«-«h«d Site «.- r? ti r L a, •> Saddl* Mowtaln W>. 2 T«T*U City talw Variety Club Boys* Ranch Lake Brid*rimort 1O^ f-Ll do . do tin S-W-- =~* «a*ita KiT.r 7*. Saddle toontain Cr*«k (to ft! HM Fk.of Trinity B±T«X> Tri». »r a. cr~t * r _ ^^ ""^ Ul*ftrti U* lu»hf rv.nk * ~" Jw . r ' W«»t Fork of Trtjiity 81r«r o .ccur fvr««t J ' rto _lnt • t*li- do Hloton, Okla. dim T -anaflla t r *do*' T n 1 rfci rto ***' *' J_ CariMgi., Okl*.— SaBlBK, MECKSS, do IVwto T ^^ do "^ ' ^ °» «r. ao ^ _^_ D .. , • ° * RlHrtMnm^ ^ ^dfl"1" ' VX' f r± Uartii T ° d«r^' ta~ _,_ P«l sti 1»J.O 1J1e, Tcx- ShmtsrlU T do * 1 3.80 2.13 4.22 1.99 7.14 l.W 2.13 3.43 AID TSltlTT 9.20 .91 .58 .3/9.48 .59 99.1 2.12 6.24 3.14 1.48 .30 1.83 ,051 ,875 1.05 .36 2.55 3.1S J.73 2.05 4.11 1.93 6.96 2.05 3.37 SIYKS B1SI 8.71 .82 .54 1^157 8.56 .43 274.4 97.4 2.02 6.18 2.87 1.42 .29 1.75 1,033 J/809 1.01 .33 2.50 3.05 »««. CM. A<«. *r.' J«lj ^oljr HOT. rtf>! Oct. «0». Julj Apr. Jan. AX- Jail Apr.' Apr. S^>t. IS Oct. »«. S^t. S^fi. S^t. S^rt.. Mc>! Apr. Apr. fbr. Oct. Apr! «OT. OK. JmM Apr. Jane Apr. Apr.' F.b. Har. Har. •or. Apr. Apr. Apr. JulT 1959 1963 1968 1955 1958 1963 1969 1959 196! 1958 1963 1968 1964 1965 1961 1966 1964 1966 1959 1965 1970 1959 1*5 1970 1921 1949 1895* 1949 1880 1949 1928 1938 1921 1949 1885 1949 1937 1946 1910 1935 1956 1970 1925 1730 1938 y 1950 1926 1939 1942 1950 1914 1938 1932 1943 1934 1939 1952 1899 1939 1926 1939 1919 1939 1930 195O 10.32 4.12 4.84 2.62 5.52 5.76 5.90 4.85 1.87 1.70 4.6 2.1 5.9 5.19 6 5.26 28.25 54 69 10.5 28 64 9.7 25 20.9 14.6 13.25 8.5 12.8 7.8 23.6 10.8 5 13 40 13 20 20 200.0 194.0 190.3 1,075.3 1,054.8 1,018.0 966.7 655.99 639.60 1,72). 2 1,645.9 1,633.9 532.17 503.79 1,315.92 1.3U.74 622.01 613.83 656.0 639.6 635.4 771.3 ^751.4 2^19 1,605 319 205 181 92 180,759 167,072 8,012 6,657 756 659 37,520 27,100 18,158 14,276 12,321 10,743 531 509 370 328 i/2,085 iA,7U 376 298 38 33 396 275 6/292,000 283,240 6/211,000 205,175 182,000 270 204 295 271 222 199 lakea in watershed »*»ich contributes y Lake Clark «aa built in 1940 downvtreaii fro* "Ermis H«v Lake' in 1«95. Club Lake and a Kmli pond now sub»erg«#iich lias upatr me of all Uk** • flood storage. *JB fro* Eagle Mt. Ras«rvolr. ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG ANN. RATIO (ACRE-IT. PER ACRt-KT) SPECIFIC WEIGHT [DRY) LB. PER CU. FT.) AVG. ANN sfsmmrr ACCUMULATION PEBSQ. m, OFNETDB. AREA FOB PERJOD SHOWN AC.-FT. | TONS AGBICV SUPPLYING DATA SABIlffi, HECHES, AH) THIMITT RIVER BASINS (Continued) 5i-a 51-22 51-23 51-21 51-25a 51-26b 51-?7b 51-28a 51-29 51-30 5i-3ia 51-32 51-33 51-34 51-35 51-36 51-37 51-36 51-39 51-10 51-41 52-1 53-2 Hun*? Lake— Kerens City Lake- Variety Club Lake Clear Fit. Watershed Site Ho. 10. do- Honey Creek Site »o. 12 Damon City Lake- do Lake Cherokee Lavon Reservoir Site Ho. 11B Kin Fk. Watershed Gar«a-Little Sim Reserroir (Lewisville Dan). * ~ ": Clear Cre«k Watershed Site Ho. 21. Upper Lake Fit. Watershed Site 23 Lake Ai.cn G. Carter Thanbers Creek Site 37 Chanters Creek Site 101-A Clear Fork Watershed Site Ho. 7. Denton Creak Watershed Site Mo. 17. to East Keechi Creek Site No. 1- Lake Corpus Christ! Hedine Lake do last Fork of Trinity River _ do Cow Cr«ek Trib. of Trinity River Trinity River • do . .- " *l . ------- 71 en 53-3 53-4 52-5 52-6 52-7 52-8a 52-9 52-10 52-11 52-12 52-13 52-14 52-15 52-16* 52-17 53-1 53-2 53-3 53-4 53-5 53-6 53-7a 53-S 53-9 53-10 53-11 53-12 53-13 53-U 53-15 53-16 53-1? 53-18 I/ Ot •toss Ranch Stock Pond Moss Ranch Stock Pond Reims Tank do Bakor Lake Calaveras Creet- Site Ho. 6 Steith Pond do Site Ho. 1 Escondido Creak CuKiirigs Creek Watershed Site Mo. 6. 3D Lake Scarborough • do Lake Bants — -Jo •• » •• • Hubbard City Lake Ho. 3 Hubbard City Lake No. 4 Rogers Lake do Hnbbard City Lake Ho. 1 rfej ' — — — Hubbard City Lake No. 2 Hubbard City Lake No. 5 Lake Law Loraets— • • — Heridian Lake Killer Lake ?os»u« Kingdom Lake flock .ruahcr Old Santa Anna City Lake — - — •ieijial capacity fron nap by stere do S. Bull Creek "». Bull Creek • Trib. of Sandy Creek Trib. of San Antonio fii-er C 1 ° " r_aia araa TOOK IVIh A<>f ' *Ar> (>••* 'do' "S"°n ° Trib. of Llano Elver ^ H rvir, " *V Trio, u c. -re Trib. of Bonito Creek Cib»lo Greek — Qm.daJ.upo i r Trib. of Deer Creek GuadJtlnpe River Basin. San Antofu.0 River do- — - — e r— * do BRAZOS Trib. of Jia Ned Creek -~° -^ do Mercer Creek — nm r (*• Oi-uHi* Croak Trlb. of E. Cottonwod Cr- Trib. of Little River Trifc. S. Cottonwod Creek- do East Cotton-ood Creek Hedbank Cree* Salt & Emory Creeks Trib. of Horse Creek d Brazos River liacncior Lrocic ftikexater Creak o photogramoetric aethods. p/i do Llano, Tex. — do — , do So T r * San Antonio, Tex. Hext, Tex. ° * Jourdanton, Tex. Bo«me, Tex. do * T Kenedy, Tex. do idd^a, «. RIVEB BASIN (SOUTH BEMD TO Colemn, Tex. Santa Anna Tex do Cooanche, Tax. Hubbard, Tot. Rogers, Tex. Hubbard, Tex. " do do Lam, Tex.- Lonata, Tax. do Meridian, TEE. do San Saba, Tex. Graford, Tex. 13_/ Colemm Tox. j ' Santa Anna, Tex. 9,350 .07 .20 .15 3.17 7.01 8.43 1.35 .769 .191 1.54 2.34 2.76 3.01 2.99 WASHINGTON) 10.8 1.17 13.76 11.65 .16 1.40 .55 .03 .11 13.0 4.74 3.30 .56 16.5 1' . 19,313 .07 .19 .14 3.10 6.70 7.94 1.34 .74' .188 1.52 2.32 2.75 2.83 2.76 KIDDLE, AND 10.6 1.05 13.57 11.50 .14 1.35 .51 .5 .03 .10 12.8 4.60 3.20 .38 .55 12,955 16.48 Oraindge ar June 1937 Feb. 1941 1909 Feb. 1941 — 1903 Feb. 1941 — 1916 Feb. 1941 Sept. 1950 Aug. 1955 Deo. 1956 Mar. 1968 July 1958 July 1960 Aug. 1951 Aug. 1955 Feb. 1951 Sept. 1955 Aur. 1953 Aug. 1955 Sept. 1952 Aug. 1955 Jan. 1949 June 1964 Sept. 1949 June 1964 Sept. 1954 June 1964 July 1969 Aug. 1958 Sept. 1963 Aug. 1969 COLORADO RIVER May 1923 May 1940 May 1923 Apr. 1940 May 1926 Sept. 1946 May 1917 May 1940 — 1913 May 1949 — 1917 May 1949 Fall 1922 Sept. 1934 1896 H»y 1949 — 1912 May 1949 — 1925 May 1949 — 1911 — 1912 Feb. 1941 Apr. 1948 Sept. 1913 Mar. 1941 July 1925 July 1949 May 1941 Feb. 1949 1910 Feb. 1941 Jan. 1910 June 1940 e« it 31,250 sq 3.7 32 38 25 4.95 11.25 2.0 4 4.54 2.4 2.91 15.42 14.75 9.8 5.1 5.1 5.9 BASINS 17 17 20.3 23 36 32 12 51 37 24 29 14 27.5 24 7.75 31 30.5 - "i- , 370,010 954,859 4.7 4.5 9.3 9.1 12 11.6 251 226 1,697.82 1,661.12 2,728.0 2,667.8 11.96 11.45 80.3 76.5 6.41 5.60 142.4 135.2 10/48.97 43.75 10/45.12 41.51 924.7 906.2 890.1 858.3 855.2 854.1 2,153 2,007 766 745 1,313 1,221 962 855 11/104.5 90.2 U/318.2 255.4 164 126.5 IgAlO 84 12/36.3 33.0 44.8 37.8 530 354 759 732 723 692 83 75 75.1 52.6 729,985 672,420 153 30 153 118 of which 11 , 900 ".649 «.639 - .595 .540 1.65 1.62 2.022 1.978 .081 .078 1.959 1.866 .361 .315 .578 .549 .078 .070 .061 .056 2.30 2.26 2.22 .77 .77 .76 - - •jq. mi. are n 34.65 66.17 47.08 45.6 27.8 28.3 49.6 51.41 45.2 43 - .21 .07 .021 .12 1.50 .49 3.79 .09 1.12 1.80 1.64 .15 .09 .67 1.12 .22 .07 .81 1.18 .334 .40 2.86 1.45 6.12 1.0 3.0 3.0 .46 .20 .69 — .71 — 1.71 - .57 .14 1.31 oncontributing. — SC9 _ S3 — 3C3 — SO — SC3 1,132 — SCS 706 — 505 3,886 — SCS — SOS 1,112 _ SCS 1,090 _ SCS 3CS 92 — SOS 97 — SCS 1,710 — SCS — SCS 907 _ SCS 1,162 — SCS — SCS 375 — SCS _ SCS — SOS _ SCS _ SCS — SCS — SCS _ SCS _ SCS _ SCS — SCS — SCS — SCS Z/ "Original" or 191.5 capacity adjusted in 1961 by range 1. i»e "Oct. 53" area and capacity. 3_/ Sediment pool oily. L/ Adjusted for l°-2 survey of Lake Dallas. y Adjusted in Aor. 1963 for detailed range survey in 1952-53-5^- £/ Determined by USGS Nov. 1961. 2/ 1951 adjusted data. £/ Deposits above Highway 190 bridge only. Sot corrected for de^ trola ost-abliahad in 1953 Original capacity doterained by spudding on 1964 survey. ll/ Daa was raised in 1925 and 1949. Capacities based on 1949 l 12/ Dam was raised in 19.25. Capacity based on 1925 level. 1J/ Includes 1,111 sq. mi. of partially contributing drainage as 3,900 sq. mi. of non^ontributing drainage at head of nwtershed. * Eatinated or assuaed. i in waterahed, excluds i Between highway and ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W THE UNITED STATES THROUGH 05 DATA SHEET NUMBER 1 RESERVOIR STREAM NEAREST TO»N DRAINAGE: AREA (SQUARE WLES) ! i TOTAL NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY \ACRE-FT.) CAPACITY AVG ANN INFLOW RATIO (ACHE-FT PER ACHt-r-T) SPECIFIC WEIGHT (DRY) LB. PER CU. FT.) AVG. ANN SEDIMENT ACCUMULATION PEBSQ ML OF NET OB. AREA FOB PERJOC SHOWN AC.-FT. ] TONS AGENCY SUPPLYING DATA BRAZOS RIVER BASIN (SOUTH BUID TO ) "IDDLE, AND :CLORADO ^IVER BAJIK5 'Continued) 53- 21 53-22 5V 24 53-25 5-5-26 53-27 53-28 53-29 53-3Cfc 53-31* 53-32 53-3U 53-36a 53-37 ^3-38 53-39 53-40 53-U '3-1,5 53-46 Old ColMM City Lake ilO dx>' Uke^tt^TirtU » • du R. G. Boll lagWDrth Stock Pood. J. S. Wan Stock PonA. Milt* Tank 7l«.rerle« Stock Pond (Horth)- Stlth lake Philpeeo Lake- do LtUleV Bi-ilUll -- u. do do do • do LlkL EiliJlnuji Site Mo. 3 Cow Bayou — • do Co** Bajou Mo. i. do Green Creek Mo. 1— do ^° do Silver I-nke Main Res. Deep Creek Site 5 — Upper Rea. Deep Creek Site 5- • do to Sulfur Creek Site 3 -- -do- Whitney Reeervolr Site No, 1O-A Hukevstar Creek Ukn Daniel • "He 9 Lower 3an J«ba Bi«er-- Hra Creek ». ..CT - _i- ~*r ai dO 0 do Trib. of Brady Cr»«k Trtb.^of Jl. M =r^_ Redbank Cr^k Paint Creek Paean Bayou (Colo. BiTer)- j~ U*i * ~° do Fiiiit^iTeait "do j j * ° „ '-^te *°" Sreen Cr.* j H. K. Trib. of Leon Ri»er- ' do° y* do i" Mid. oloradG or ^ L.^..,., M,.r do to ' **"rtn °r 1 An^ do GOT^e, .reek Morado R,,.r ColaMai , TBJL. „ . •• do ^^cr^~ ° ' 'at'* * do' ~*~ da Brady, Ttau Bro«TWod, T-tt. La», T« do Pioneer, Tax* Brownwod, T«x. 1 . yo. T 'A C°'dj ~" do C *iaja TOOL. j^ ' Pfc&JJ, ex. do do Dublin, Tax. Brad T BTTU1J, ta' "^ , ' ui-j» » i An — !!Sl_± d *I" n T ng3, ex. ftreckenrldge, rex. --» -»•-. T« 0.73 12.0 225 74.4 1.73 2.60 .80 .13 1.04 9.04 ,649 " 42 1.40 5 'lr 3.42 3.57 .37 2.91 2.19 4.75 10.81 ,656 4.26 15.^6 115 3.03 0.69 11.9 224.7 1.71 2.58 .35 .60 .13 9.00 1,533 2/1,645 41.4 1.32 5.2C 3.19 3.38 .334 2.72 2.18 4.55 10.58 .2/3,480 4.02 ,4.59 113 2.88 Nov. June fer. Jane Ibr. Dec. Feb. Jm>e Feb. K»r. «W Feb. »"«- ipr! Feb. Jiilj Feb. Sept. Apr. Feb. Feb. 0»:. Oec. Feb. »J Nov. »"«. »»«. Ipr. July Sept. HOT. •»«. Apr. Jan. Apr. June Julj *ug. July Aug. July J»n. June July Deo. «o,. Aug. Dec. Ap,. Dec Sept Har. A»g. *>». Jen. iept. 1906 1940 1923 1941 1920 1941 1922 1941 1900 19*1 1937 1941 1927 1941 1936 1941 1941 1926 1941 1925 1941 1932 1940 195° 1930 1935 1936 1947 1964 1929 1954 1955 1960 19*5 1970 1956 1969 1953 1960 1955 1957 1962 1967 1910 1960 1953 1961 19'3 1961 1961 1965 1970 1959 1962 1968 1941 1959 1951 1966 1965 1966 1949 19^0 1960 33.6 17.-5 20.75 19.5 41 3.7 14 4.8 14.6 15.9 7.6 19.6 4.9 1.0 11.8 17.0 25.25 4.75 5.04 4.69 13.2 6.8 1.8 5.2 5.2 50 7.9 7.9 4.42 5.1 2.8 5.8 - 6/ 7.4 14.8 1.4 21.4 299 273 610 560 1/1,637 1,275 iO,7U 9,032 33 29 20 14 13 12.2 4.5 3.6 1.12 .80 1O2 93 173 149,925 145,720 135,963 )9,378 33,717 31,588 22,026 15,427 6,583 5,917 458.5 393.3 375.4 366.7 l.'flS 1,833.53 925.18 881.30 1,095 1,080 1.O65 1,063 153.3 145.0 1,326.7 1,295.7 15.2 11.2 732.94 7O8.42 703.41 3,229.2 3,224.7 3,223.3 '2,013,600 1,999,500 1,409.81 1,367.81 3,164.89 3,157.99 10,731 9,515 645.79 635.49 1.011 .983 .917 1.144 1.028 .23 .05 .00 .98 .24 .19 .821 .688 .98 .96 .93 .93 .435 .296 .755 .644 .072 .053 .38 .33 .32 .6 .6 .6 .70 .62 .85 - a. 9 i*2.2 •M.5 *5fl.5 *5«.5 49,2 _ — 7b.57 73.6 — 49.9 — ,- — 55 62.6 US — 0.67 .2.4 .06 1.19 .058 .66 .16 .24 .10 .63 .07 .361 .325 .695 1.28 .487 .236 .64 — 10.40 -J.69 l.U 1.19 2.0O — .11 — .527 — 1.4* .23 1.22 .22 — I/. 02 .55 .71 -34 .49 .1*6 - _ 329 299 886 1,631 621 — 687 — — — 1,572 — 1,149 3.335 — i/S — — 250 — — y* 749.88 — — — 512 723 XS SCS scs SCS scs SOS SCS SCS SCS SCS SCS 9CS CS SCS SCS SCS 5SS SCS SCS SCS 3CS SCS SCS a. SCS SCS iCS SCS ------- i ri i s I s i i ft rt 38 3 6| R £ 3 B I " I ' ' I ' I ' ! ' I ' ! ' ! ' I Sfl t H i-l J tV ^ O O O O O O t I "' I -1 I ' ! ' I ' I ' ! ' ! I 1 I !f^i£)£>l2l'ii' i fi b S . "" i I 5 15 I ~-l£~-3-3U-,,IQ~r4 ^^^.^^^^^^^S: r i o- i i w i ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W THE UNITED STATES THROUGH 1970 ^ 00 DATA SHEET NUMBER ' RESERVOIR STREAM I 1 NEAREST TOf N DRAINAGE AREA (SQUARE MILES) TOTAL ] NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG. ANN. WFUJt BATTO (ACRE-IT. PEB Al.RM'T) KECmC •EIGHT DRY) LR PER CU. FT.) AVG. ANN. samam ACdMDLA-nOK POSQ. H. OF NET W. A3EAFDB PERIOD SBOtJN AC.-FT. | TONS AGCMCY SUPPLYBIG DATA RIO GRiSDE BAiIli (BSPAJELA TO TOUT CJUITKU <7-lb 57-2 57-3a 57-4 57-5 57-7 57-11 57-12 57-15* 57-16 57-17 57-19 «-? Klaph*nt Butt— Wo Gr«*. RiTT _, j£ - *• to *> |y - - *l • Ao . - *» Corofl»ld Ifcrti (1) — Trlb. of Eio Ptwroo tt»«^ Cornfiald fa* (2) do C«-nfield Utah (4) <*• _' *° - , _. .A, ... — do Oorafiald *.* (15) do- San Luis (1) do • •* ** Trlh T J n ™*" do Caballo Arroyoa Sit* 1 Oodcrwood Arroyo J? A _t* ^ 9 ™-OJO ^ JO Sit* /3 (Rawonaa Arroyo) Haaon«8 Arroyo 10 ^l Horth *ltm Sito f2 toi-th 3u« ioyu **? IF A fl TjiJ A RoJwj (HnLi.h 7«llt/ Ariuju »j. *^. inT^- Pwcoa RlTor -^k. • rto- J° tin do do •Jo i- *T4*oi, .J.«o Arolany- trz-i I»c ___^ , do Klaphant Butt*, *. Hex. 25,923 do do do do — *> .-do- ... Troth or Cons«»qu«nc«»,2/3O,7OO 3^ 1. fex. B^noU, 1. NKK. 93.1 a**, «. ««. .29 do .87 —— * 1-ls . 1 nj. do do (U> do 1.04 do 1 06 B.™llllo, «. Itox. 1,034 _i_ do Cuba, 1. ttot. .74 Dcrrr, *. Max. — .87 rto 1.17 j uprea PECOS HTVER BASI« °~ n ai-.sba<. , . ex. *, 5,866 — 93.1 .28 .85 1.17 1.03 1.05 66 1,034 .74 .87 39.9 3,749 ofvn ' - Jan. Oct. pr. pr. NOT. 2«i Apr. Oct. Apr. Oct. Apr. Oct. Oct. Oct. Doc. Oct. Oct. Jan. Julj Jul/ HOT. D*c. Sapt. pr' July 1915 1925 1947 196"? 1957 1929 1951 I960 1951 I960 1951 I960 I960 I960 I960 1953 1952 I960 I960 1953 1958 1965 1952 1962 1959 1968 1931 1936 5.0 5.5 6.5 12.2 19.9 27.4 4/10 V 4/10 4/10 4/10 4/10 4/7 4/8 Vs v^ 5/4 25 5/1.6? i/6.33 6.7 6.3 15. 2S 2,634,900 2,339,380 2,270,300 2,219,000 2,137,219 343,990 3J58 24.0 10.3 54.1 2.6 22.1 17.4 9.2 3.0 3.1 .3 16.3 22.6 19.6 19.0 117,213 115,821 112,809 *3.0 73.21 232 160 69 190.82 17O.91 141.25 1,180 1,150 156,750 110,655 5,64? - 2.2O 2.31 .190 .160 1.446 .620 3.127 2.607 .711 .313 1.277 1.006 -474 .155 .639 .023 6.593 .676 2.155 .683 2.844 2.810 2.763 2.737 15.9 14.9 6.9 4.76 5.5 •9.4 15.4 12.7 _ .946 .797 -- - •60 60.0 62 80 — — _ __ — — . — •75.7 *75.7 •75.7 _ m noo •110 •no 98.5 85 — •73-5 •73.5 •73.5 76.7 .475 .361 .22 .0761 .27 4.89 1.06 1.32 .40 .60 1.67 2.15 .01 .58 2,43 .317 1.1M .162 .62 .64 3.30 6.03 27.16 .35 1.55 .083 .876 1.03 .281 6/.0263 .0599 - 621 357 470 _ _ - — — — 523 1,860 267 1,547 7,187 LA, 44* 102,597 750.9 2,869 _ — 1,410 1,649 450 - a scs OS OB OS OS OS OS nil OS scs acs acs scs acs an at ------- T* oo * uaruL L "1L fl ui^ji-iLamlu Jlte fl T* j 7° ft *7 ™ncrv"t *^ do * rf- 1° *in ** jT * * Aft *lrD°" **^ - i*o*rnon f20 ^ San Carlos (Coolidge Du) 0 do Stock Tank Ho. 16 (Bryce Dam) Roosevelt- Salt River Project- j° do ° A do ^_ do da do da do Agu Frl* Rlw ^^ da ™ ^ rin -i in «. T r «* da " **" ° ~° do da do do Cap! tan, 1. Max.— 122 93.92 do da do . COLOUDO RIVER BASIN (BHJ3W HOOTER DAK Williams and Lower Gila Hirer Basins GILA RIVER BASIM Phoenix, Ari«. • 1,450 1,4-Wt m », »_j 11 r«ifi .11 drtrt , Ul*. J-.9OO ,VU"J do j do ii-I 6*? 69 Ml, r ,_ r , do do — Oo do •ov. »aj Jane Dec. Jan. July *v Oct. MT Mr. Feb. Jan. Feb. Oct. Feb. Oct. Feb. Oct. Mr. *v »pr. Oct. Nar. Dec. Jan. Jan. Oct. •ov. Oct. MX. *v Jan. Oct. Oct. MX. Oct. MX. Oct. ipr. Feb. aov. Feb. Jan. Mar. Hav Dec. Oct. Sept. Jan. Jan. Jan. 1904 1910 1915 1925 1932 1940 1956 1959 1959 1961 1962 1963 1965 1955 1965 1955 1965 1955 1965 1955 1957 1959 1965 1955 1956 1958 1959 1965 1954 1965 1955 1957 1958 1958 1965 1955 1965 1955 1965 1928 1941 1928 1935 1937 1947 1966 1936 1941 1909 1914 1916 1925 1935 1939 1946 10.42 6.42 4.50 10.08 7.50 7.08 16.50 .42 1.58 .83 .92 1.92 10.67 10.67 10.67 2.17 1.91 6.50 1.75 1.08 1.00 6.75 10.92 2.17 .67 .75 7.00 10.67 10.58 12.9 6.3 1.9 10.0 19.6 5.2 5.7 1.8 8.9 9.3 4.0 7.0 73,000 61,500 45,500 42,000 40,500 38,655 2/39,400 4,972.14 4,946. 54 4,896.60 4,818.00 4,796.41 4,749. 54 4.77 3.52 7.20 1.59 4.09 1.59 2.21 1.60 1.52 .49 5.45 4.30 3.62 3.02 .55 23.78 16.05 20.19 18.04 17.99 17.58 16.05 15.60 2.20 6.55 5.77 184,500 176,456 1,266,837 1,232,725 1,230,695 1,209,343 1,170,118 11.43 5.13 1,522,200 1,495,460 1,460,150 1,425,813 1,418,013 1,398,430 1.381.580 5»-6 5»-7 58-8 58-9 58-11 58-12 58-13 58-14 60-1 60-2. 60-3 60-4 I/ Total storage ehows a gain of 9,180 ac.-ft. since 1947 survey attributable priaarily to compaction. 2/ Includes 2,940 sq. Hi. in closed basin in Sen LniB Valley, Cole. 3/ Drainage aree between gaging station below Elephant Bntte Du and gaging station below Caballo Dan lees original water surface area of Caballo Besexvoir at elevation 4,225.3. ^/ Bnnoff seasons. 5/ Tljes periods adjusted. y Coejpected sediieent for 1,080 eq. ed.; values for 16,03O sq. id. are given in appendix .344 .276 .232 J.7Z .159 .153 046 .149 •70 5/62.4 •75 75 75 75 75 •75 •75 •75 •75 •75 •75 •75 •75 •75 •75 •75 •75 •75 6.054 5.891 5.882 5.780 5.592 1.886 1.853 1.809 1.767 1.757 1.733 1.712 •70 •70 •70 •70 •70 •70 .116 .120 .238 .023 .013 .017 .004 .65 .34 1.01 .25 .26 .01 1.46 .24 .83 2.75 2.63 2.49 1.53 .45 1.39 .14 .7* .31 .70 .46 .432 .455 .090 .179 .168 1.75 .819 3.350 .670 .145 .850 .418 1,060 555 1,649 403 424 16 1,500 554 2,380 391 1,352 4,555 4,260 4,130 2,519 734 2,262 228 1,241 505 1,142 752 scs 3CS sea scs 3C3 GS 1,248 5,107 1,021 221 1,296 637 ?/ Increase in capacity due vainly to compaction. 8/ Only surface samples (1.0-3.1 ft.) in approxlmtely 1/3 of r»s«r»lr area below crest. 2/ Drainage area is 100 ae. plus pipe flow from Pearson Al. t-hieh has a drainage a 10 ac., plus pipe and emergency spillway flow fro« Pearson AS, which haa a drainage are 1.80 sq. KL. * Eotiimted or assumed. a of of ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W TOE UNITED STATES THROUGH 1970 DATA ^.va* STREAM NEAREST TOWN 1 DRAINAGE AREA (SQUARE MILES) TOTAL DATE OF SURVEY NET : PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVtt ANN. INFIX)* RATIO (ACHE-FT. PEB AC8E-FT) iPEOFIC RIGHT [DRY) La PER :u. rr.) AVG. ANN stxatan ACOMJLATnN PE8SQ. •*, OF NET OB. AtEAFOB fSUCtH^MH AC.-FT. | TOWS ACBICY SWPLYKG DATA en O •0-5 60-& 40-T «M •O-* 60-10 40-11 40-13 40-13. 60-14 40-H ID-It 40-17 •o-u 10-11. 40-20 „ * -B- Bt, fe. I, * •o- m. •.. 5 do ^* a. iw< «.. < *> B^c OaftaMa ate. 4 9f Trii. of KUXMOI Bry Uka — BtlftBa M». «f OU« tt»«r ai do nuaaninii do Loaar »«*• "aak f*ot« «aa» fc^fc. 1 >»a.lbaB *•»*>- 3 *> •fetal fc. 3 * Bl*Mr fmtm Ifcah Foot* "»* «dU*« Trtt. of Foot, lull ItoU IhA PM M Tl*b. of (Mia Mm. imilii^ r^liannr tad A Trtb. of QM«D Cr«dc minim n»nnn n™i *a — *> Big ••*« Ml. ttak fl 1Mb. of Cmtaonial Utah — W* bra ». T«* *2 do •»»*„* do •tot TMk *> ,1,. do Open- «» T»ik tl«n- IhA BirojMbAla Mt. Tank A THb. of BrowR>s CaoTon U.A J«H* *.*. hrt«i4«, Arix. Saffbrd, Arix. do— -. - - Sunflow«r. Ariz. Safford, Arls. — — Flor«nc« Junction, Ariz. —do. Tonopah, Ariz. do -£ — _do- — — Saloaa, Aril igulla, *rlz. do • -• - Solonn, irlz. J BtSIK (Continual) l/t." t-1' .a 10.92 2.18 .36 12.3 5.6« .6 .38 .2 .9 •.80 1.78 .33 21.9 .6 1..9S .71 5,312 5,618 .60 .33 1.09 .65 .51 .U 2/.60 2/1-88 .29 1.83 .11 4. 60 .21 10.92 .36 12.3 5.63 .6 .38 .2 .9 V.63 1.78 .38 *7.0 .6 4.95 .74 190 5,614 .58 .33 1.09 .65 .51 .U J/.60 9/1-88 .29 1.83 .U 4.57 HOT. B3T. Sapt. H&r. Nov. •or. Ho*. HOY. Oct. «•»» fcr Pab. »V fcj Oct. June June F.b. iug. HOT. Jan. tor. Oct. Kov. Jan. Jan. July July Juna Oct. July Oct. *J Hay Juna Oct. Oct. Oct. Juna Oct. Jan. Jan. July 1936 1958 1917 1958 1938 1958 1947 195« 1*2 1958 1943 1958 1%1 1958 15*9 1960 1940 1960 1941 1960 1954 1960 1936 1958 19*8 1959 1954 1959 1949 1959 1946 I960 1936 1958 1950 I960 1939 1942 1950 1964 1945 1950 1963 1936" 1964 1936* 1964 1931 1961 1944 1%1 1960 1964 1960 1964 1954* 1965 1945 1965 1960 1964 1944* 1964 1958 1964 1957 1964 1964 41 20 2/7 2/12 1/5 4/6 11 20 19 6 22 11 5.4 10 14 22 10 3.50 8.33 4.9 13.1 •28 •28 30 17 4.3 4.3 •11 4.3 JO 6.3 7 .6 279 253 2.94 Z.5. 2.55 .70 14.7 .0 .43 .0 3.0 2.7 .8 ,6 6.0 4.1 4.7 2.8 6.8 3.9 6.00 1.83 14.8 13.0 5.7 2.7 1.6 1.3 6.0 3.8 1.9 1.4 24.2 19.5 3.4 1.8 132,608 179,480 7/179,548 178,4*8 67,900 8/142,830 139,238 19,10 17.10 b.462 5.325 2,10 1.00 9.33 8.95 21.30 ZJ.O6 11.46 11.26 1.27 .67 7.61 4.08 10.09 9.93 2.21 ^iS 6.50 158.79 154.24 153.16 2.847 2.582 .516 .44* .009 .002 .218 0 .009 .008 .005 .004 .312 .214 .385 .230 1.889 1.083 .368 .112 .17*. .084 .232 .183 .099 .073 .209 .168 .254 .134 .241 .507 .494 •1.705 •1.527 •1.04,9 -.864 .197 .094 1.3*6 1.291 •7.83 •7.74 •4.88 *4.79 .397 .209 .759 .407 *6.5l *6.41 *.22S '.173 •11.25 •11.02 •1.649 •1.796 •1.784 •75 •75 ««5 •75 •75 •90 •90 •85 •90 •SO ««5 •75 •8O •85 76.2 72.6 60 60 47.6 •50 91.97 52.5 46 •50 76.9 •76.9 .05 .008 .85 .10 .006 .006 .29 .26 .75 .78 .13 .15 .15 .03 .06 .23 6/-154 .044 .049 .12 .12 .033 .034 .11 .U .09 .13 .015 .18 .14 .39 _ 81.7 13.1 1,573 9.8 9.8 559 520 1,388 1.530 261 278 49 105 426 199 190 43 44 114 ia> 180 148.7 15 196 234.5 653.2 sea 9CS 3C3 3C3 S3 S3 3d 913 S3 3CS xs 9CS 9C8 9CS xs xs 3CS SC3 Bt B> scs so 3CS scs 3CS S3 scs 3CS 3C3 3CS acs 9CS ------- 60-41 60-42 60-43 6O-46 60-47 60-48 6O-49 Three 3ar B Deoris Basin 0 0 . ^ "^hree B*r " Debris Basin 0 0 0 0 ^ 0 -lo Tb Bar D Deb &a r "n 0 0 d _jo d j Tft-ie Bar p Debris Basin "° ° 0 0 ,j 9 *t cnnc.. u. Horsethi-f Basin L71U[ ^ke Granite Basin n ° Tank " C _ t _ ""^do Trib. of Bock Creak rf It a do to 1° j° j° ri da H ° ~° 0 ' rt rt d ~° 0 0 ° do j^ d dQ 1° 1° _, ^° ainut uulcn d rf° Horiethief Canyon — Lynx Creek — V rri R' i . crae Kivcr ° jcn • a Trio. Flying »E" Wash ° "do ^ a Roosevelt, Ariz. .O?3 0 do- do ° j° rt iC ^4° do .0- •10 rt do j° °~ T>^ do .l-b do do do 0 rf rt H do do- J° -O .107 0 do do do j0 -O -c i^^stone, Ariz. .6 do do ... Crown King, Aris. .85 Prescott, Ariz. 18.14 o i,, & ; icottsdale. Aria. .06 A AA onopah, Ariz. .00 Wi k b A J "Q " urS> - j-z. . V do .073 Aug. Oct. c n^t* Oct. Oct. Oct. Oct. Oct. .U9 Aug. Oct. -~t- Oct. Let. Oct. .126 Aug. Oct. Oct. Oct. Oct. Oct. n"' Oct. Oct. .107 Mar. Oct. Oct. Oct. Oct. .6 June June June .35 Nov. «10 Mov. 3 /„ °V* AJg. .06 Jipr. «Ug. .^45 June Apr. .77 Kay Sept. .I2"f Hay 1959 I960 1961 1962 196 L. 1965 1966 3967 1966 1969 1970 1959 I960 1961 1962 196A 19o5 1966 1967 1968 1969 1970 1959 I960 1962 1964 1965 1166 1967 1968 1969 1970 1963 1963 1964 1965 1966 1967 1963 1069 10?0 1961 1967 1963 1967 1934 1969 1<^2 1939 1967 19U 1970 1939 1967 1956 1970 1965 107C 1.17 1.00 1.00 2.00 1.00 l.CG l.oc 1.00 1.00 1.00 1.1' 1.00 1.00 ^.00 1.00 1.00 1.00 1.00 1.00 1.00 1.1' 1.00 1.00 2.00 1.00 1.00 1.00 1.00 1.00 1.00 ,51 1.0 1.0 1.0 1.0 1.0 1.0 1.0 6 36 6 23 -:9-2 27.9 H.3 11/.23 LITTLE :OLORADO AND SAN JUAN RIVS? BASINS •erted from Hawk Hollow. Zuni, N. Hex ------ do Oct. 1954 — Hay I960 14/6 U/.01, 18 17 14 13.5 42.4 35.6 1,472 1,460 89 58 21 79.1 77.3 .99 .91 334.8 148.0 .6 .6 1.7 1.7 .44 .37 1.07 1.06 *.32 *.21 1.529 *1.91 6.63 20.87 20.39 1.59 1.46 1.425 .630 •uo mo •uo •uo mo •110 •uo •uo •uo mo •uo •uo •uo •uo mo mo •110 •uo •uo •uo •110 •110 •uo •110 mo •uo mo •uo •uo •110 mo •110 •uo •uo •uo •uo •uo •uo 75 75 - - - - 74.8 94.1 88.2 12/L8.77 12/44,969 12/4.66 12/U,159 0 0 12/.55 12/1,313 12/.14 12/328 12/.27 12/656 0 0 12/.14 12/328 0 0 0 0 12/5.57 12/13,345 12/.67 12/1,008 12/.67 IgA.oOS 0 0 0 0 12/.34 12/804 0 0 0 0 0 0 0 0 12/12.70 12/30,427 12/3.73 12/8,937 12/.63 12/1,521 12/.04 12/95 f.08 12/190 .08 12/190 0 0 0 0 0 0 0 0 0 0 12/.37 12/886 12/.09 12/224 12/.19 12/448 0 0 0 0 0 0 13./.08 13/2,°16 .2 326 .25 410 .22 — .197 — .236 - .09 — .21 342 .16 328 .10 192 PS FS SCS SCS SCS SCS \/ Drainage area includes 1.97 so. mi. diverted from Hawk Hollow. 9/ Drainage area is aiiallest area that could be pc-gitively V Heserroir wag fjll of sedl-nent in 1954. 10/ Storage capacity at original spUlway crest elevatio ^/ Const^-cte^ ! 043 t -leaned 1953. elevation 0.53 ac.-ft, 4/ Constructed 1041, cleaned 1952. ll/ Basin cleaned as needed to maintain capacity. from the 4.17 sq. -^. above this daw. 13/ Basin filled during storm of 9-5-70 and undetermined 6_/ Baaed on total drainage area of 5,812 sq. ni. before construction of Horseshoe Dara upstream. 14/ Runoff seasons. 7/ Increase in caoacity probably flue to compaction. * EstinBted cr assumed, 8/ Capacity Lncreased 76,130 =ic.-ft. b? ijiatallation of spillway gates in ^une 1950. - storage capacity at eroded spiUwoy nt of sediAant ascapea froa pond. ------- SOMIIAHYOF RESERVOIR SEDMEH TATWN SURVEYS HADE Bi THE UMTED STATES THBOUGH BWO DATA ITOMBEB RKSSKVCSE STREAM IfEAREST TOWi DHAJHAGE AREA (SQUASZ MLES) TOTAL NET DATE OF SURVEY PERIOD BETWKEH SURVEYS (YEARS) STORAGE CAPAaTY (ACHE -FT.) CAPAorr AVG.ANN. BfFUM PS) ACiE-TO •Plane HLKJil! L&ns •». FT.) A**a,ARM. rSSMT* OP 1ST 98. ASUUKMi ***** aW*" AC.-FT. | TOHS ^^ BATA to OCLOSACO i«D 3*3 J«i« BIT3X 3A33K! (Cottin 61-3 61-4 61-3 61-4 61-7 61-6 62-1 62-2 63-3 62-4 62-; 62-6 62-7 62-S 62-9 62-10 62-11 63-13 62-14 62-15 62-16 62-17 63-1 do do JO : |8». - - •Bumf* tank I do do do Ql«KSrtli Tru* mb. fenr Lew Craaft — "•" "J* Wb.JJa««.a»« Matt- *wt Kail Taas — -*j %nu Tm* H nib. Plsfclae %rUg Bi Breofcdtir teak— trtb. of JeSoe^i HwS~ do *> M«;s rut Cbaroti Ssody Oajra Kaab * ~^ (Tf F h Prarf- troCU^ Ce««re°l Streeteir*. i-i " Bill 9aow Pond . Trib. Santa Clazv 9±rsa do do 40 Saanflaa, IrM. -48 do .55 IWto,4rta. .25 aemaato, Aria. 2.45 ov *-rt-«'. *•*>• •» nv- . .^o .10 qp|tx)B^go BXmS Ba3B! (HAJX3 CS03S j«,.- — . do 57.«S I(K2i«a Bbeeesia., A2^a. 1.27 IVaao^E, fall. 5/3.49 b^TiociM, Otai. 9.2 do p St. Gaergs, Utah .03 de — te .09 do 1.09 — de .85 do .59 de 2.3 r — — — ------- 8 3 888 I I I I I I I I I I I I I I I I I I II ! I IS 8 8 ISM I M; .1 '& 'S' R*«i ,-t it t 8£ * 8 88 R« SK* . 3 P3fi*K RX fc £*<« S f S -*O«O*J^»*VoJoJ^j"*-4 "|J«N *l*jO'«Oii?««V'***l«>'OO«lJ|i4*t*-t"-t-'fi'p^''O'O^3'*«O'iO>^w>'O-*-*«*v«*\«<">f*\pj « * J«H rfrf-1 H- ! •«-«OOOO <«-«OOOO -O O O -O O O t^^^^^N J ^1 ,4 ^^1 .HO? IfVrHrv liNrJiN | ' «OOO -Oc^Oi-JOOOOOOOOO >O«^O^OOOOOOOOO * *"* -H j|SI?IBIISS*l?l?ilsllll I15'?! S £ £ 8 S f= 2 3 d »<9- a ------- SUWIARYOF RESERVOIB SEDIMENTATION SURVEYS MADE » THE UNITED STATES THROUGH 1OTO DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE TOTAL MILES) NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG. ANN. INFLOW (ACRE-FT. PEB SPECIFIC •EIGHT :DR¥) LR PER CU. FT.) AVG. ANN SEDUENT ACCUMULATION PERSQ. M. OFNETDB. AREA FOR PERIOD SHOWN AC.-FT. | TONS AGENCY SUPPLYING DATA Oil Itall <3-i> Trlb. or Badger Uuti- 63-11 63-13 COLORADO UiXB BASH (ABOVJ KAILS C2OS3IHG) Cunnleon, Dolores and Prewont RiTar Basins (Continued) tack, Colo. •— 0.059 — — — — . — — — — — — _ — — .019 — — — — — — — — — — .158 — — — — — — — — — — . — .048 — — — — — _ — _ — — — D«c. July HOT. Oct. HOT. HOT. HOT. HOT. HOT. HOT. •or. Oct. HOY. HOT. Oct. D.C. July Her. Oct. Sor. HOT. Nor. SOT. HOT. HOT. HOT. Oct. SOT. HOT. Dec. July HOT. Oct. HOT. HOT. HOT. HOT. HOT. HOT. HOT. Oct. HOT. HOT. Dec. July HOT. Oct. HOT. HOT. HOT. Hov. HOT. NOT. HOT. Oct. NOT. NOT. Oct. 1953 1955 195* 1957 195S 1959 1961 1963 1964 1965 1966 1967 1966 1969 1970 1953 1955 1956 1957 1958 1959 1961 1963 1964 1965 1966 1967 1968 1969 1953 1955 1956 1957 1958 1959 1961 1963 1964 1965 1966 1967 1968 1969 1953 1955 1956 1957 1958 1959 1961 1963 1964 1965 1966 1967 1968 1969 1970 __ 1.6 1.3 1.0 1.1 1.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 — 1.6 1.3 1.0 1.1 1.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 — 1.6 1.3 1.0 1.1 1.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 — 1.6 1.3 1.0 1.1 1.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 12.92 12.18 12.18 11.90 13.90 11.64 11.31 11.25 11.21 10.73 10.82 10.62 10.15 10.13 9.99 4.52 4.31 4.31 4.19 4.19 4.16 4.14 4.12 4.03 3.89 3.89 3.81 3.74 3.83 8.45 6.05 6.05 5.94 5.94 2/24.80 24.18 23.89 23.45 23.15 23.23 22.86 21.88 22.12 8.10 7.69 7.69 7.58 7.58 7.51 7.38 7.10 7.05 6.81 6.81 6.54 6.07 6.18 6.13 5.71 5.39 5.39 5.26 5.26 5.15 5.00 4.98 4.96 4.75 4.79 4.70 4.49 4.48 4.42 9.62 9.17 9.17 8.91 8.91 8.85 8.80 8.76 8.57 8.28 8.28 8.11 7.96 8.15 2.14 1.53 1.53 l.W 1.50 6.28 6.12 6.05 5.94 5.86 5.88 5.79 5.54 5.60 4.60 4.37 4.37 4.31 4.31 4.27 4.19 4.03 4.00 3.87 3.87 3.72 3.45 3.51 3.48 •93 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 __ •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 "90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 __ •90 •90 "90 •90 •90 •90 •90 •90 •90 •90 •90 •90 •90 «90 7.30 0 4.75 0 4.40 2.71 .51 .68 8.14 1A- 3.39 7.9* .3* 2.3« -_ 6.85 0 6.32 0 1.58 .53 .53 4.74 7.37 0 4.21 3.68 l/- 9.50 0 .70 0 2.15 1.96 .95 2.78 1.90 i/- 2.34 6.20 i/~ 5.4Z 0 2.29 0 1.46 1.46 2.92 1.04 5.00 0 5.63 9.80 y- 1.04 15,»9 « 9.S02 — 8,638 5,482 »97 1,329 15,947 — 6,645 15,615 664 4,651 _ 13,427 — 12,380 — 3,095 1,032 1,032 9,285 14,443 — 8,253 7,222 — 18,622 _ 1,365 — 2,840 3,846 1,110 5,459 3,722 4,590 12,158 — __ 10,624 — 4,492 — 2,859 2,654 5,717 2,042 9,801 -~ 11,026 1«,194 — 2,042 OS as as ------- SS-i II i in :?:lsI• I• f y • I• i• s§• svi•!• I• I•!• I! I I M c V&fri' I • I • r «• I • I • I • I • *»*» •(•( ft , M M I II I ! M ! I I I ! ,- ! I II I M M M M ! M M I M I I M M !!!!!! I M I M M I I I I ! 8 fssirsfsgff.fjrsfifjr^ oooooooooooooooo ooooooooooooooooooo ooooow ooooow PS cJ« C o*fc »-r-*" 5ai Si; Si *«8 »5s;i!ok ftfesssc tt 8 a ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL [ NET DATE OF SURVEY ! PERIOD BETWEEN SURVEYS (YEARS! STORAGE CAPACITY (ACRE -FT.) CAPACITY AVtt ANN. INFLOW RATIO (ACRE-FT PER ACRt-TO SPECIFIC (EIGHT (DRY) LB. PER CU. FT.) AVfl. ANN. SEDWENT ACCUMULATION PEHSQ. tO. OF NET DR. AREA FOB PERIOD SHOWN AC.-FT. | TONS AGENCY SUPPLYING DATA en COLORADO arras BASH (ABOVE HALLS CSDSSIBG} Gumison, Dolorvo and Frwont EUror Basins (Continued) 63-20 63-21 64-2 64-3 64-4 64-* 64 7 64-« 65-2 """jo""" tlr to * __ do do East St. Louis Creek Weir £ do llL HW-1 "oatcap Wash Watershed - South Soda Cre«k Weir . North Fish Cr«k Weir do • West Walton "reek Weir _-;0 __ - do Niles Haalea Pond Ejjt ^y°n -do--- „ ^'do'8 do do Easi, St. Loula Creak do do— .-do Roatcap fasti ' c"u" v South Soda Creek do • Trib. Walton Creek do 40 — Trib P " el do Trib. Twelve Mile Wash j. ^ar.^n rcoc ^ Weber River do(. -do 7 do Col do — do—- do do- oo Steamboat Springs do do do _-JO do- do Echo, Utah Snnt i Utah do - — - 3.10 3.10 - __ _ 11.6 11.5 G8EKN RIVER BASIN , Colo. 3.40 3.4G 2.24 — 1.33 1.33 — — 11 11 1.41 1.41 .65 .65 G8ZAT SALT LAKE BASIN 732 732 SEVIER RIVBH BASIN 5.0 4.9 Oot. Oct. Oot. Oot. Oct. Oot. Oct. Oot. Oot. Oot. Oot. Oot. Oot. Oot. Oct. Oot. Oat. Oct. Oct. Oct. •or. Oct. Oct. Oct. Oct. Oct. Oct. Oct. Oot. Oot. Oct. Oot. Oct. Sopt. Oct. Dec. Oct. 1955 1956 1957 195* 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1964 1965 1966 1967 1963 1969 1970 1970 1942 1962 1967 1968 1969 1970 1968 1969 1967 1968 1969 1938 1968 1936 1968 1967 1942 1968 1896 1954 1930 1957 1895 1940 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 6 20 1.0 1.0 1.0 1.0 1.0 1.0 1.0 30 22 15 26 58 24 3 75 — — - - — — 810.0 718 1/870 - — . *5.0 •5.0 »2.0 •8.0 1/3,850 28,730 73,900 •65 607 598 __ _ — — — — — «1OO — *100 — «100 — »ioo •100 — *100 •6.9 — •.236 — •.286 «60 — »135 — 135 — "135 — «135 — «UO — «70 — «60 — *70 •90 .098 — .733 4/77.1 .364 V71 .008 .006 «90 — — __ O.OO5 .011 .002 .002 .0003 .005 .0002 .O03 .003 .002 .001 .001 .001 .002 .002 .001 .002 .002 .001 .002 .» .14 .005 .0003 .001 .016 .020 — 2/.T9 .cai 2/.67 2/.23 .124 .104 .47 .024 _ 10.24 21.12 3.84 3.52 .64 *32 2.88 5.7« 2.24 1.73 1.50 1.50 4.00 5.45 1.35 3.40 4.20 2,90 4.25 183 13.43 1.08 1.62 11.74 38.28 47.90 — 1,204 14 1,021 450 208 161 — — n re xa n n FS SCS SCS SCS 303 BB SCS SCS ------- 66-3 66-4 66-5 66-4 66-7 66-8 66-9 66-10 66-ru 66-12. R fcT F rrt dn° n v — ' itoeHj o TL 1 *• 1 rt Sari Bi-lrt :>«n.flr arias* Chalk Creek Debria Baain rt Fiddler* Canyon Debris Baaln- ftll Canyon Retarding Structure -. „. "T. ) CT \ dO* r L " " _. ., . rin rtn °? Fiddler.* Canyon T1 P3QT»TF 7° IffUrO^ C 1 t Tti. t do _ CI^ * _ Utah do' Utah ""'"dn** ' •pnl, ton „ '*do'' " ii ci nr.h n » »* , J.-.U — 900 — 10.0 — 25.0 — 2,W£ — i9.5 508 900 9.92 23.4 6.9 2,436 1,089 «*0 12.6 19.5 HOT. r«b. HOT. «OT. Uov. HOT. Dec. *>». Julj H>r. HOT. D«c. DM. 19W 1915 19W3 1890 1940 1893 mo 1909 19U) 1926 19U> 1910S/ 1938 1908 1932 1936 1946 1955 1947 1956 1957 I960 42 25.8 50 47 31 14 28 24 .5 10 8.5 9 3 299 23,260 21,509 2,115 790 667 430 9,000 8,550 2,500 2,200 81,200 74,010 250,000 234,462 44.12 0 0 15.00 208 ltd. - - — __ .002 0 0 «.089 •1.600 *1.431 - - - __ *70 •75 75 •TO •TO .038 .134 .029 .508 .620 3.10 ~.106 .5% 6/-T3 J/.U a/, us .38 1,112.9 228.7 221 578 90 xa S3 90S SCS SC3 SCS SCS 90S SCS 67- Ul -3 BASIS {»CHTHHi3TBal PAST in ULITOHIilA, HEVADi DTD ORKXTH! GS£------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 Ol CO DATA SHEET RESERVOIR NUMBER 7O-a» Ch«t.«wc 70-10 La*w» • TO- 11 btclno i : 1 STREAM WEAKEST TOWN DRAINAGE AREA [ DATE (SQUARE WLES) ' SURV i 1 j TOTAL NET 3JU.70S SEA AMD SOUTHERN itLIFORNIA XJASTAL AND GS1AT BASIN DRAIh Trib. of Loa ln^«l«a tLi-rer — • — do 5.40 4. -.5 Apr, 1Y1U. of Sa:. Jaclflto RiT.r H«it, Caiif. 66.0 15.3 trtb. of Kw-port Baj Orang., Calif. .*>; .72 ^sb. Bnclno Cr»* Loa Ang^«o, Calif. 1.42 1.30 Maj 7CU13 r_Ln_jut -• »rrr«1op« »•! 1 «y 81™r Lancaster, Calif. 2.-4 2.37 Oct. 70-13b littl* fcx* Irrigation M«t.- Little tock Cr»ok nOatalii, Calif. 68.0 67.84 Apr. , _ _ ^ rlrt -. ,. - — — JHfl» ~r£" -* - -*. - - oet. _^0 — — do - TO-Ue L!T» Oa* DM _to — 4o ___<*> — do (to Li« 0»k CrtxA • •• La?«rn«, Calif.- 2.3 ^.3 — do • t*o — — »OT. A, - -do --• -. - ">^. ~Jj — *- *« — — Har. ID I" Kjima 'Vt-trtrwmti "rr* San Diego, Calif. 112.0 109.4 Mar. 7O-l6b Pr*do Flood-Control R«a«rtolr Santa Ana ftlTar Corona, Calif. 2,233 1.1J1 S«pt TO- 17 ftoca-ianbir-i Canyon $/ — tecklflgbirt Can/on Arlington, Calif. 11.6 11.5 70-18c fUn— n Floot-Control Basin "ujxw$i Cr^k • San Farnando, Calif.— 147 U6 $«pt eta T-t-19 Br«a ?. C. 5»sin-— _do do - a"t • IP do :|>n * d ^'8 .rtr, _ fW-1 . 70-20c G»KM«11 (San G*bri«l Dam #2) San Gabriel Riw Aiusa, Calif. — 39.2 39.0 Apr. rfO ik> 10 __£- ___v. PERIOD STORAGE OF BETWEEN CAPACITY EY 1 SURVEYS (ACRE -FT (YEARS) ACT Continued) 1931 -- 36,500 1939 1M '6,i36 1939 3. 10,077 19U) *8 11.702 1938 — i7t 1939 1/J 266 1921 — 3,229 1939 18 3,210 1913 — 7.A37 1939 l/2t 7,393 1921 — k,17 1936 iAl-0 1,139 1938 3.0 3,6iS 19^3 5.C 3,U>i 1946 3.0 3,352 1951 5.0 3,297 1953 2.2 3,313 19192/ — 2i7 1929 6.3 Ji7 1936 7.0 2U2 1939 1.! 228 1952 1..5 221 1961 9.0 17O 1962 1.0 166 196" k. 3 i/221.8 196<- 1.75 197.1 197C 1.75 251.1 1910 — 66,767 1935 25.7 60,699 I°t8 12.6 58,933 19U — 222, SW 1960 18.9 216,960 19U. - «1,000 19U 26 961 19^40 — 35.8UO 19U .8 35,200 191.3 2.3 3)., 100 19/.5 2.1 33,500 1962 16.2 33,265 1969 ^.58 29,700 19i.2 — i.,16S 19i.9 7.5 4,097 1935 -- 12,881 1936 .8 12,298 1938 2.2 10,766 1939 1.6 11,029 1°*0 l.C 11,102 1941 1.0 10,915 1043 1.9 10,501 1045 1.2 10,536 1946 1.7 10,597 1947 1.0 10,634 1957 10.2 10,585 1958 .•• 10,446 196 •• ..1 10,228 1966 3.7 9,999 1969 2.75 9,339 1937 -- 8/53,344 1938 9 47,191 T940 2.1 46,335 1941 8 45,862 1942 1.0 '.5,759 1943 l.C 44,032 1944 1.1 44,388 194' 1.0 44,342 194P 3.0 ..3,825 1951 3.0 43,928 1953 1.2 43,853 .71 .97 .612 .643 .642 .512 •85 •«5 .72 .25 .15 .275 .130 .12 2.48 1.4 1.62 6.IS 28.3 1.69 .23 .94 1,190 J..84C1 710 185 4,460 1,330 460 278 SCS 3C5 SCS scs 3C3 SCS ------- •61L ~ ~ - ~ ~ - ' G UOfSJSAfQ$zi 60 S 2? SO 9 92 02 i*7 I f £0 2 ZVT . 6S'£ LI T TT T . c? f^T" auoiBifuippry -- — - PUP 'urea 8i - iO 80 iO 17 • TO 90* 65. r • S£- «!• L ' £*7 C*7' &7 9T) esi £56 761' I A (?? OOc OIL en IDT 8*1 VT STS'T 6£I(T 7t£ T 6ZL t 5£0_ TiO 68T SBQ'Qi ATS'ff *^f ^T'Cf viiL^st AO* f ^»//- 8ii,^8t. y?ii2 ^Q«fZ i« . Q UBg iq ps BSJT; »2miT». i V I £ r./- 0 ^. t. I L i9 C 2°.^ c6 - AT 2 fii'T f?* /• /-.*, " T L 8 6 6 I •T 0 I 8'£ c IT I C . r.^^ *• ?'T •c [Toj^uo= -pu -be vie /Tl p BEU-TQ nreg sapnt^ui /of " " "Tsed" "a*'">'s ^ ?^/ . Q£6T -irer ^-V S-7 7^ ^ , ?C T ^UB^ " , j ' , ,, . 6e6l "1=0 AP6I/OI o'6T Oi6T 'AON 696T ^ „ i7ol * 0 oto T ,J 0961 ^ °fj ovol u ?^T • ^ • r~ c ^tO^i ^ _1 ^ *-*L£/D t I L£ / .9^ ?Q^T *AO TQ^ 'Od ^ op op Of. op op op op op 'JTIBC 's-iopuais Op op op op op op ^ op Op P ^ op Op op ~^~ . . op p op op op op op op p p " op • °P op op O p Op p p Op °p op F " p op p op 0 •pof j»d op op op op op cp ^ op op ^-t^ UO^-^G 2Ta Op op Op op op op op op op op op op op op OT- op p op op op op op op or • . . ^_!^_!!s_ op op Op op op op op OD ^ op op op p op p 2tr[jnp jriooe jo eaneasq pa^rximoo •Buoseee jjoinu uu ps op Op CP Op 0[, Op op ^ op °r trfseg -5 ',., UO^^BQ SIQ ct "" op °l- op Op °t- p op Jp -«rea UOTSJBAIG suoisd^p^ry 0[, Op op op ^ op °l- ^ Op °t- ot , op !2™__^!.'!op-J!!- 01- op op Op Op op Op *" p op Op Op ^ °N /9 3t A °N K °N /T »a A 39t-0i LO ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE » THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL | NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG. AWN INFLOW RATIO (ACRE-FT PER SPECIFIC •EIGHT [DRY) 1,8. PER CU. FT.) AVG. ANN ACCUMUl^TrON PERSQ Ml. OFNETDR AREA FOR PERIOD SHOWN AC.-FT. | TONS AGENCY SUPPLYING DATA AND SOUTHH1N CALIFORNIA COASTAL AND (5SKAT DASIJi DRAINAGE (Continued) » 3anta Anita F. :. Basin-- Santa AnlU Creek — Arcadia, Calif. 10.8 70-»= Sit Tojwwa r. C. Beiln Big TXJunga Creek Sunland, Calif.- 05 O 70-3CU F.»t------- 8 88 Be 8 I II II I ! I II ! I I I I I I I I ! I I ! I I I I ! I II I I I ! ! ! I I I I I I I I ! ! ! II ! I I I I I I u c A I IS33fJ:SP£;*33 i I I M I ! I i I I I I I I ! ;O •O*O^*u^*^w\lf\J*<. *<^ Si "' -^ i-o i tVr* *tv I N ol t~ •* *wr?H |^OH<^ ^ r*J -4 (\ t H H <^i *^ f* .fa o. I I 11 * lit) Jl i i i i 4 . jl|TfT77= t $?°fl>?? : ' ! : ! ! i : i ! !,-' ' ! i i ! ! : i f I f"\ '.: s !ll rt 1 i i i I « 1 !8°, tT J= 1 tn i i L, f |f ' , " ,T • 1 1 ^ " T • 11 ,. -1 1 • , !, ! j , 4 ' "7 . i i H i 4 i „, I j : i :lV n 8* ! ' L ,T i - !n ;, i7 !' • , ^ i |T n • i i i i i ,i .. '| ' ! I 1 I - 4 " " i ! <^< i •0 ;< 1 i I m •v -t "* - ; | I TJ ! i I 1 •D ' j ! -c, - I ! i i , i ^ ^ i ! „-! F-61 ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE W THE UNITED STATES THROUGH »70 DATA SHEET NUMBER RESERVOIR STREAM NEAREST T09N i DRAINAGE AREA (SQUARE MILES) TOTAL | NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG. ANN. INFLOW RATO (ACRE-FT. PER ipcctnc (EIGHT PRY) LB.PER :u. FT.) AVG, ANN SEQMENT ACCUMULATION PEBSQ.IO. OF NET DR. AREA FOR PERIOD SHOWN AC.-FT. TONS AGENCY SUPPLYING DATA SALTC* SEA AHD 30UTHHH1 CALITORMIA COASTAL AM) OKEAT B&SXI OttlBAGS (ContlnMd) Slam fed™, Cilif 0.60 0.60 Sept. 1946 J-I*. 1947 S«l*. 194« Svt. 1949 Sept. 1950 Sept. 1952 S**. 1959 Sfft. 1962 S^t. 1968 3*1*. 1970 3«ptl 1941 hpt. 1943 a«t*. 1945 1946 s«pl. S^t. Altadon*. Calif. do S^t. s^.! s^t. s^tl A«. s^t! S«pt. Sept. .21 Sept. Sept. S^l. S^t! Sept. Sept. 1943 1944 1945 1946 1947 1948 1949 1950 1952 1956 1960 1961 1966 1970 1936 1938 1941 1943 1944 1945 1946 1947 1 1 1 1 1 2 4.8 3.0 6.0 2.0 5 3«pt. 1949 S*pt. 1950 3«pt. 1952 3q*. 1964 U 3*pt. 1970 S«pt. 1936 So>t! 1940 3»pt. 1941 S«pt. 1942 Sq*. 1943 3»pt. 1944 S«pt. 1945 S^t. 1946 Sq>t. 1947 3^>t. 1948 S«pl. 1949 3^*. 1950 Sept. 1954 3«pt. 1959 3^>t. 19TO 11 ' 1939 19U y- i/- — 2/0.84 >.t3 .86 2.33 0 0 .09 0 0 0 1.59 1.17 27.86 2.87 2/.69 29.0 8.14 8.74 .27 10.3 Z.87 .56 3.13 1.15 0 0 0 4.07 .36 3.17 1.58 j/a.2 11.7 7.03 .34 15.7 4.59 1.11 .59 .41 .07 2.66 .02 1.67 2.05 5.28 5.87 J/46.4 47.6 3.9 4.8 .24 1.71 7.86 1.95 ------- 05 O3 70-44c Gould Debris Basin Gould Canyon Channel La Canada, Calif.- do—.—_ do — do do do do 70-45a Haines Debris Basin hsiies Canyon Tujunga, Calif. 1.53 -io do — do fto io —.—do — do • do do do do do -— -do- -do— do do- do 70-46c Hall's Debris Basin Ball - Beckley Canyon U Canada, Calif. 3/.S4 do do do do do do do do do — do do do— 2/1.06 do . do . do do—- do do do- do- do do di I/ Canaelty of debris basin varies. Debris excavated at various times. 2/ Sediiientation values as comouted by LACFCD are based on complete water yea Sept. 1948 1 — — .019 — Sept. 1949 1 — — — 0 — Sept. 1950 1 _ — _ 0 — Sept. 1952 2 — — — 4.57 Oct. 1956 4.1 — — .U — June 1958 1.7 — — — 19.05 — Sept. 1963 5.2 — — 4.76 — Sept. 1966 3 _____ 10.14 Sept. 1968 2 — — — 3.10 — Sept. 1969 1 — — — 46.9 .30 Sept. 1936 1 I/— — — 2/31.2 — Sect. 1938 2 _____ 41.3 Sept. 1941 3 — — 3.30 Sept. 1942 1 — — 0 — Sept. 1943 1 — — _ 22.0 Sept. 1944 1 — — — 6.17 Sept. 1945 1 _ _ — 3.07 — Sept. 1946 1 _____ 2.77 Sept. 1947 1 — — -43 Sept. 1948 1 — — 0 Sept. 1949 1 — — — 0 — Sept. 1950 1 — — —0 Sept. 1952 2 — 5.47 Sept. 1964 12 — — 1.23 Sept. 1966 2 ------ 16.67 Sept. 1968 2 — — — 11.5 Sept. 1969 1 — — — 24.6 .47 Sept. 1948 1 I/— — — 2/0 — Sept. 195O 2 — — — 0 — Sept. 1952 2 — — — 5.32 -one 1958 5.8 — — — 3.29 Sept. 1962 4,2 — — -- 5.83 Sept. 1966 4.0 — — — 9.04 Sept. 1968 2 — — 1.98 — Sept. 1969 1 — — 28.7 1.53 Sept. 1938 3 i/— — — 2/6.93 — Sept. 1940 2 — — _ 2.31 — Sept. 1941 1 — — — 5.09 — Sept. 1943 2 — — 4.22 — Sept. 1944 1 — -- — 3.58 Sept. 1945 1 — — — 2.59 Sept. 1946 1 — 0 Sept. 1947 1 — — — .37 — Sept. 1948 1 — _-o Sept. 1949 1 — — 0 Sept. 1950 1 — o Hay 1952 1.6 — -- — 1.57 .84 Sept. 1936 1 I/— — — 2/17.2 Sept. 1937 1 - 13.7 — Sept. 1938 1 _- — _ 75.4 — Sept. 1941 3 — — — 12.0 Sept. 1943 2 — — — 17.9 Sept. 1944 1 — 6.10 1.06 Sept. 1945 1 — 2.97 Sept. 1946 1 — — — 1.00 — Sept. 1947 1 _____ 2.60 Sept. 1948 1 — — — — Sept. 1949 1 — — — — Sept. 1950 1 Sept. 1952 2 — 6.40 — Feb. 1957 4.4 — — — .14 — Sept. 1959 2.6 — — 11.03 — Sept. 1962 3 — — — .063 — Sept. 1964 2 — 4.48 Sept. 1968 4 — — — 3.49 Sept. 1969 1 „ — _ 34.4 Drainage area 0.84 sq, mi. to 1945; L. 0659 sq. mi. beginning 1945. ------- s*§ai MiSse; fc > 2 o ! 3 S C r f ^* Bile II ll 8 B S B I I II I II I I I I I I I I I I I I I I ! II I I ! M II I M I I I I M I I M I I M I II I I I I I II I ! I I I I £c rfj H00000-l«««,j^jm 000-I.J,^.; .}-rf O rf , , , H ^H I I I I I I I II II I I I I I I I I I t I I I M I ! M I I I I I II I I I I I I I I I I I I I I I I I I I I I I M I I I a s R * °' i M i 11 i 11 M 11 11 i ' 11 i 111 i i i i i i i i ' I i i i i i i 11 M i 11 i ' i i t i it i 11 it i 11 i 8 3 R * °' II I I M ! I I ! M I I I I ' I I I M I I I II I t I I ' ! II I II I I I I II I I I ' ! I I II I ! I ! II II II w\ i! J f I 1 1 i tC '! 1 f>r 1 I I ! • •$€£ £££ MM I!1 I I i ! 1 ! i I F-64 ------- Paradise Debris Basin Paradise Canyon — LA Canada, Calif. .96 .96 Sept. 1945 1 l/~- — — 2/1.18 -do- . do 4o — — Sept. 1946 1 — — — .92 Sept. 1947 1 — — — LOO Sept. 1948 1 — -U Sept. 1949 1 — — -10 — Sept. 1950 1 — — — o .58 Apr. 1952 1.4 — — — 5.38 Htr. 1956 3.9 — — „ •* 1.84 Sept. 1936 1 I/— - — 2/11.0 Sept. 1937 1 — 6.89 Sept. 1938 1 — — — U.9 Sept. 1939 1 — 2-95 — Sept. 1940 1 — 4.75 — Sept. 1941 1 — — — 11-6 — Sept. 1943 2 — — — 9.03 — Sept. 1944 1 -- — -- 3-00 — Sept. 19»5 1 — — — -51 S^,t. 1946 1 — — .23 Seot. 1947 1 — — — .37 _ Sept. 1948 1 — — -- -15 Sept. 1949 1 — — " 0 Sept. 1950 1 — — 0 — Sept. 1952 2 — — — 2.25 Sept. 1959 7 — — 2.81 — Sept. 1966 7 — -- — 3.41 Sept. 1970 4 — — i-W 1.3 Sept. 1946 3 I/- — — i/-69 Sept. 1947 1 — — — .32 — Sept. 1948 1 — — — 0 Sept. 1949 1 — _ 0 Sept. 1950 1 — — 0 Stpt. 1952 2 — — 1.23 Apr. 1957 4.7 — — — -05 — Sept. 1966 9.4 — — — 2.07 -_- — Sept. 1969 3 — 10.0 Scholl i>ebris Basin Scholl Canyon Glendale, Calif. .66 .66 Sept. 1947 2 I/— — " 2/.32 ao —do- do — — Sept. 1950 1 — _ o Q5 do do do- - Sept! 1970 9 — - - .88 f-n ^0-550 Shields Debris Basin Shields Channel La Crescenta, Calif.— .27 .27 Sept. 1938 1 I/— — — 2/77.0 '- — '- — Sept. 1939 1 ~ 10.1 Sept. 1941 2 ~ 10.9 — Sept. 1943 2 — 5.85 — S«pt. 1944 1 — 2.33 — Sept. 1945 1 — — — -52 — Sept. 1946 1 — — — 1.04 — Sept. 1947 1 -- — — -04 Sept. 1948 1 — — — 0 Sept. 1949 1 — — 0 Sept. 1950 1 — — — 0 Sept. 1952 1.5 — — — 10.9 Sept. 1961 9.5 — — — 2.07 — Sept. 1966 5 — — — 6.81 .23 Sept. 1938 2 I/— - — 2/22.6 Sept. 1939 1 — 57-° Sect. 1941 2 — 4.4 Sept. 1943 2 — 8.30 — Sept. 1945 2 — — — .65 — Sept. 1952 7 — — — 1-09 — S«pt. 1961 9 — — — .06 — Sept. 1968 7 — — — 3.30 — Sept. 1969 1 — — — 56.5 .84 Sent. 1947 .6 I/- — — i/° Sept. 1948 1 — _ 0 Sept. 1949 1 — — 0 Sept. 1950 1 — — 0 Mar. 1952 1.5 -- — — 3.56 — Feb. 1956 3.9 — — — 1-13 1.65 Sept. 1943 3 I/— — — 2/4.22 Sept. 1944 1 — 2-81- Sept. 1945 1 — I'76 — Sept. 1946 1 — — 0 Sept. 191,7 1 — — " Sept. 1950 3 — — — ° — Apr. 1952 1.6 — — 2.73 — Sept. 1958 6.4 — " — -37 Sept. 1960 2.0 — — — .75 I/ Capacity of debris basin varies. Debris excavated at various times. 2/ Sedimentation values as conmuted by LACFCD are based on complete water year. ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE TOTAL SOLES) NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVG. ANN. BAUD (ACBE-FT. PEE ACBE-FT) SPECIFIC (EIGHT ;DRTO O.B. PER CU. FT.) AVG. ANN SEDHENT ACCUMULATION PEBSQ.ML UK NET DR. ABEAFOR PHUODSBOWN AC.-FT. j TONS AGBICY SUPPLYING DATA 70-60 70-610 CT> Ol 70-64 70-6 5k 70-66 70-67« 3ALTO8 3E4 AND SOUTHJ3N CO»3TAL AJO OSSAT 1US1K DUIHAOI (Continual) 3«*. 1942 1.08 15.5 1/.64 1.6 .58 Aohurn D«brl« B*«in Bradbury D«brl« Basin — — — __ — — 1.00 — _ 10,0 _ — — — — — — — _ — — y.64 __ — — — — — .25 — — __ — — — — — — — — — — — — — 1.59 — .58 — — .19 — .6fl — — — — 3«pt. 1944 Sapt. 1945 Sapt. 1946 Sapt. 1950 Sapt. 195J 3«Rt. 1959 Sapt. 1966 3«pt. 1969 S.pt. 1946 3**.. 1947 Sapt. 1950 Sapl. 1938 Sapt. 1941 Sapt. 1943 Sapt. 1944 Sapt. 1950 3«pt. 1952 S«pt. 1953 •V 1956 Jan. 1959 ^pt. 1960 S«pt. 1964 Sapt. 1966 Vpt. 1968 3»pt. 1970 S^it. 1945 Sapt. 1946 3*pt. 1947 S^jt. 1948 Sapt. 1949 S^it. 1950 rah. 1952 Apr. 1952 Sapt. 1956 s«pt. 1958 S*pt. 1936 S.pt. 1«37 S^rt. 1938 3^*. 1940 Sapt. 1941 3------- 88 88 88 H88 888H8 B 8 B I I i i i : i i M i i i i i i i i i i i i i i i : : i i i i M I i I i i i M i i i i M i '. i i i M I i i i i i i M i i i i i M i : i i i i i 5! ft as ss; ss sss ' I I I ' I I I I I ' I "* I I I I I ' II ! I ' M I I I ' I I I I ' I I I I ' I I I ! \XSSSXS i >. I. O « f t- SfdSsiS j 8» *" ** 2 i ' i M ' i i ' i i i"' i : iH' i i i i ' i i i ' i i i ' i i i c t 8 3 F) a 11 Ill] 3 ^ I i i i o i ill\\s\ ! 1 M r'l ft ' fr' "j|4f a 11 I ! PC ? it it i it £ * * 4 F-67 ------- SUMMARY OP RESERVOIR SEDIMENTATION SURVEYS MADE Df THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL NET DATE OF SURVEY PERIOD BETWEEN SURVEYS (YEARS) STORAGE CAPACITY (ACRE -FT.) CAPACITY AVa ANN. (ACKE-FT. PEB ACRE-FT) SPECIFIC •EIGHT PRY) L8. PER :u. FT.) AVG. ANN snwnrr ACCUMULATION PDSQ. ML OF NET M. AREAPOi PEHJOD SHOWN AC.-FT. TONS AGENCY SUPPLYING DATA C-3 OO AID 30t. S^t. itopt'. In.' In. Jwi. AFT. In. *r. Jon. *"«.' J«n. D«. Oat. Ihr. Ifcr.' S^t'. iimmiiliiHiHsijjiiiiiiijMlii 1956 1957 1958 1959 1967 1968 1969 1941 1944 1961 1943 1949 1959 1961 1967 1949 1969 1966 1966 1968 1969 1970 1970 1961 1969 1963 1966 1964 1968 1970 1961 1969 1970 1958 1969 1970 1967 1969 1970 1964 1966 1969 1970 1966 1969 1970 1960 1962 1969 1164 19W 1956 1969 1963 1967 1965 1967 1959 1962 1968 1970 1963 1967 .8 1.0 1.0 8 1 1 3.0 16.6 ~6.6 9.3 2.2 5.7 1.6 .9 .96 1.86 .43 1.41 3 8.5 3 4 2 8 1 11 1 2 1 1.92 3 1 3 1 2.6 7 S 12.91 4.2 2.7 2.8 6 2 4.2 i/— — _ _ - 16,720 1.00 17,437 1.04 17,296 1.03 J4.670 — 34,276 — 33,987 — 33JK5 — 2.30 .234 - - v- - 7,033 10.0 6,615 9.45 it/ y- - - -* y- i/- 9,285 .90 6,718 .65 V- u- V_ - 2/30.1 — 39.3 - 17.5 .4 — 3.1 — 2.91 — 1.51 — 13.32 123. — 1.16 — 0 2/ 71 — 2.54 — 2/8.81 — 1/10.4 - 13.5 — 2/6.77 - 16.3 — 2/66.7 — 2.78 - 2/10.50 — 21.65 — 12.70 — 19.'4 12 4 2/2 95 — 7.45 2/19.1 67 2/5.23 ------- see SOS SOS COS SOS COS COS SOS COS SOS COS COS COS COS COS SOS SOS SOS COS COS SOS COS COS SOS soc COS COS SOS COS CDC E T9-itT/8 — ow — 184 — ZZI 8£*Z69/8 %4/8 9£i/5 — 4Tt — tCT — 99*61 — Z'OTT — if9 — £'J6 — 92 — 6TZ — 5oe — T6Z — 75T — iJI — 5-01 — m — 9« — WZ — 1t£ — LTZ — i'01 — LSI — 961 — izy — — ~ _ - cr/S — 61" — 168- — n- 8i4'/8 Z8t'/9 960 75 — 890* _— si- — 9iO' — II' — 99' — £50* — itO' — toe' — 2«r — 00£- — TOT' — £90' — oco- — Z£T — i9T" — OTZ- — TSZ" — 191- — ito- — TV V 41 "A — w — TVT 2'8ZA 5f6>^ 51* — 04. — 0£. — 01. 44. 01. 49. 09» — 01 — OC — 71 — SI — oe — QU — 04* — £9* — S1» — Ci* — cu* -_ 29^ — 05 — ?9 — Z9* — C9 — Z9. — S4 — 01 • — 09. — 09. — — _ - CO ir.i 'fm-»» i*»«o PIWIPTW 901-0. >n»»e «m»o P«<»VTV< wi-oi ------- SUMMARY OF RESERVOIR SEDIMENTATION SURVEYS MADE IN THE UNITED STATES THROUGH 1970 DATA SHEET NUMBER RESERVOIR STREAM j NEAREST TOWN DRAINAGE AREA (SQUARE MILES) TOTAL j NET 1 1" DATE OF SURVEY PERIOD BETWEEN STORAGE CAPACITY SURVEYS i (ACRE -FT. 1 (YEARS) CAPACITY AVG. ANN INFLOW (ACRE- FT PER SPECIFIC 'EIGHT ;DRY) LB. PER CU. FT.) AVG. ANN SEDIMENT ACCIMUI.AT1ON PEHSQ Ml. OF NET M. AGENCY SUPPLYING DATA AREA FOB PERIOD SHOWN ! AC -FT. ! TONS SAK JCAQUIN AND KEEN RIVLR oASINS AND ADJACENT COASTAL QRA IMAGE (Continued) T«aVettl» R««5rroir Ko. 1 Teak«ttl« Cr»«lc Fresno, Calif. "" do j0 0 ^ -rtrt ~rt rl 0 ° ^ ^° "" ri° j ° ° H ° ri ° do- °~ . rto 7° ~ A j ' ° do- 0 0 rt 0 ^° -ao do 0 -no 0 0 io FaU FaU Fan FaU Fan Fan FaU Fall Fall Fall Fall 'ill Fan Fall FaU Fan Fall FaU Pall FaU FaU FaU FaU FaU FaU Fan F«U FaU FaU FaU FaU Fall Fan FaU FaU FaU FaU FaU FaU FaU FaU FaU FaU FaU FaU FaU FaU Fall FaU Fall FaU FaU FaU FaU FaU FaU FaU FaU Fall FaU FaU Fall FaU 1938 1948 1951 1955 1956 1957 1956 1959 1960 1961 1962 1963 196* 1965 1938 1941 1948 1951 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1938 1948 1951 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1938 1940 1941 1948 195137 1956 1957 1958 1959 1960 1961 1962 1963 1964 1%5 1956 (1 1957 1958 1959 1960 10. C 3.0 4.0 -^ 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 — 3.0 7.0 3.0 4.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 — 10.0 3.0 4.0 — 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 — 2.0 1.0 7.0 3.C — 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 938-56) 19.0 1.0 1.0 1.0 0,39 .18 .002 1/.352 — .079 .068 .050 .030 .015 2/.066 .134 .078 .021 .0022 2/.101 .131 .127 .109 .040 .007 2/.U7 .222 .181 .178 .182 .178 .159 .129 .127 .130 .127 0.0271 .UOO .0078 .0591 — 0 — .3158 0 — .0065 — .3228 - .0*89 — .0054 — .0146 — .0084 — .028O .0110 — .0241 .0059 .0003 .0462 .0572 .0066 .0250 .0080 .0166 0 .0032 .0032 .0015 .0474 .0026 .0204 .0112 .0160 .0073 .0042 .0003 0 .0049 .1457 .0619 .0338 .029 4/-.013 ------- 71-36 71-37 71-39 71-40 71-41 71-42 71-« •T.-/J, 72-la 72-2a 72-3 72-4 72-5 72-6 72-7b 72-8 72-9 72-10 72- lib 72-12 72-13 72-14 72-15 72-l6a 72-17 72-18 I/ Overt 2/ Sedin y Last sediment was 4/ Loss ji/ Perio 6/ Retire -V Origi 8/ Origi do Salijias Soys Ranch Ai Oibralter do do rf° p -janttt ollcla Success Lake do -do do Lake Kaveah {Terminus do A 0.0 Big Canyon ° Blodjott Bullarda Bar Co*!* (V*n Oeisen)-- 1 do „ , Dan) _ Paulke Lake ("alae Lake) Gerber — te^alia Stony Gorge — Misselbeck Lake Pillabury (Sco*t , , Uatacoula Bar itf) Ac Mllliken Dam) — Onion Creek No. 1 do- - - do Onion -reek No. 2 A A d° n ljrc* °- 3 GO db a- t lent removed in aunmer . itiy. _ ,„ H° Trlb. of Natividad Creek— ° Santa Inez do Tule River — do rt° Kawean River— cr _rc °° ."r 0 0 Big Canjon Creek Tib. of Co^es River- North Tub« Rivev T T % -ittlc bton; -recK N, Tk. Jenney Creek — Trib. of Burch Creek Little Butte Creek — Stony Creek — S. Fk. Cottonwool Creek Eel River u- n 1 1 r> til n Croclc Onior, Creek, trib. of Amer. liver. 1°~ j° do -° " ° 0 sits taken in 19J6; sediment r> ratershea as a whelp. 1956, '0 Nov. 15, 19%. ed from 1965 survey. 0 Salinas, Calif. Santa Barbara, Calif. - 0 0 Portarville, Calif. , ^0 A Leiaon Cove, 3alif. 3A CRAMPS TO 1 " H H French Torn, Calif. :a»ptomdU., :allf.- frt* " -M * itonyrord, ^a^i>. Shasta, Calif. Corning, Calif. Chico, Calif. Elk Creek, Calif.— — Redding, Calif. Potter Valley, Calif. - v f i t r ap^' j Soda Springs, Calif.— ^ H do A .13 .13 .205 .203 216 6/202-2 - 425 425 393 393 _ 560 560 , EEL AND tl'SSIAN RI\"ES BASI 5.7 5.6 5.1 5.03 5.50 5.48 3.12 3.05 480 479 130 129 11/101.5 98.9 .71 .68 .31 .28 li/8.23 8.08 li/199 197 12.0 11.8 283 284 .71 .69 10.5 10.4 .19 .19 .48 .48 .65 .65 vy •irainag 12/ \$ a/ rom Oct. 1 , 19"), -&l =srt II il/ Feb. 1954 Nov. 1956 Oct. 19537/ Sept. 1964 Sept. 1964 Oct. 1919 Aug. 1923 Aug. 1944 Feb. 1956 Aug. 1969 Oct. 1955 Oct. 1965 Sept. 1960 SOY. 1965 HOY. 1967 Dec. 1968 June 1953 Sept. 1956 Dae. 1968 Nov. 1961 Nov. 1967 Jin. 1953 Aug. 1969 June 1966 1927 May 1960 May 1966 SOY. 1934 Oet. 1945 Mar. 1940 Oct. 1945 Oct. 1919 Jan. 1939 June 1928 Oct. 1935 Dec. 1910 kc-v. 1962 1851 Dec. 1945 June 1917 Dec. 1945 Jan. 1918 Jan. 1946 Nov. 1928 Nov. 1962 May 1920 Dee. 1945 D«e. 1921 May 1959 — 1953 Nov. 1958 1924 Oct. 1958 - 1957 1959 I960 1957 1958 1959 1958 1959 e basin after Spillway ele Based on the Excluding 3 The natural ., 1798-F. Net sediment Estijnated or jj/1.8 1,013,200 6/3 1,011,950 2/9.65 11 9.34 — 8/8.40 13 8.15 — 15,296 3.83 13,674 a 7,720 11.42 14,777 13.5 9,654 — 101,200 10 98,730 — *86,160 5.2 86,160 2.C 83,610 1.1 83,680 539,665 •".3 539,115 12.2 534,465 — 149,599 6 147,099 16.58 10/192,574 313 36 21t 3 *775 36 660 6 643 200 11 195 — 258 5.6 254 — 31,500 19.2 28,893 7.3 7,840 52 48,940 — 130 94 120 _ 190 23.5 182 3,718 28 3,648 — 1!/50,OOO 34.1 48,160 4,300 25.5 4,086 94,396 37.5 86,785 183.0 5 181.4 2,000 34 1,938 .114 1.0 .f'i 1.0 .097 1.0 .093 1.0 .083 1.0 .081 l.C .069 — .191 1.0 .205 1.0 .186 ation 748 (limit of 8-7 1914. vation (flashboard eras natural drainage area. sq. -d. above P. G. & E .612 .611 .42 .33 .21 .41 .27 .681 .681 .660 .06! .51 .81 .803 .389 .382 .07 .12 .29 .24 .24 .80 _ .29 .248 .228 C39 .033 .033 .032 .042 .026 .026 .0^2 .062 .067 .061 -59 surrey). t elevation *62 *65 •65 52 «62 *62 •62 •62 •62 "7.5 "50 50.3 44.7 46 •70 *70 55 54 78.3 48,8 54 «75 73 — Spillway reservoir 50,900); '1. 0." reclamation capacity curv» (3-31-45,, UjG loss - treated as 0 gain. assumed. .04 54 .29 392 .23 325.6 .10 141.6 1.96 — .43 - 1.38 — .58 658 *o ^o 3.2»4 4,3'!3 -.163 -218.7 .074 100 .186 252 .745 1,006 10./3.79 .48 1.063 .63 686 .56 642 .069 67.2 .217 217 .284 433 .749 1,140 12/.37 U/443 .147 173 .971 1,656 .307 326 U/.27 11/319 .711 1,161 .71 1,129 .04 — .074 — .071 — .0004 — .0206 il/.ocoo — .0273 from Stony Gor