PB83-245225
EFFECT OF ANIMAL GRAZING ON WATER QUALITY OF NONPOINT RUNOFF IN THE PACIFIC
NORTHWEST
K.E. Saxton, et al
U.S. Environmental Protection Agency
Ada, Oklahoma
August 1983
U.S. DEPARTMENT OF COMMERCE
National Technical Information Service
\
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EPA-600/2-83-071
August 1983
c" B83-24 5225
EFFECT OF ANIMAL GRAZING ON WATER QUALITY
OF NONPOINT RUNOFF IN THE
PACIFIC NORTHWEST
by
Keith E. Saxton
Lloyd F. Elliott
Robert I. Papendick
Michael D. Jawson
USDA-SEA-Agricultural Research
Washington State University
Pullman, WA 99164
David H. Fortier
USDI-Bureau of Land Management
Coeur D'Alene, ID 83814
EPA-IAG-D6-C030
EPA-IAG-78-D-X0249
Project Officer
R. Douglas Kreis
Source Management Branch
Robert S. Kerr Environmental Research Laboratory
Ada, Oklahoma 74820
This study was conducted
in cooperation with
U.S. Department of Agriculture
Pullman, Washington 99164
R. S. KERR ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
ADA, OKLAHOMA 74820
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T
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO. 2.
EPA-600/2-83-071
3. RECIPIENT'S ACCESSiqiv>NO
PB8 3 2 A 5 2 2 5
4. TITLE AND SJJBTITLE , „ . „ , , _ „
Effect of Animal Grazing on Water Quality of Nonpoint
Runoff in the Pacific Northwest
5. REPORT DATE
August 1983
6. PERFORMING ORGANIZATION CODE
7 K^TE?R^axton, L. F. Elliott, R. I. Papendick, M. D.
Jawson, and D. H. Fortier
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
USDA-SEA-Agricultural Research
Washington State University
Pullman, WA 99164
10. PROGRAM ELEMENT NO.
ABPC
11. CONTRACT/GRANT NO.
EPA-IAG-D6-0030
EPA-IAG-78-D-X0249
12. SPONSORING AGENCY NAME AND ADDRESS
Robert S. Kerr Environmental Research Laboratory
U. S. Environmental Protection Agency
P.O. Box 1198
Ada, OK 74820
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/600/15
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This project was initiated to evaluate the effects of summer grazing cattle in the
winter precipitation regions of the western intermountain basins of the United
States on the quality and quantity of nonpoint surface runoff. Emphasis was placed
on erosional, chemical, and bacteriological characteristics of runoff from a
typically managed summer pasture to determine the potential contribution of this
practice to nonpoint source pollution. The results show that bacterial quality is
related to livestock, but there is considerable doubt that indicator bacterial water
quality standards developed for point sources are appropriate for assessing non-point
source bacterial contamination.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. cosati Field/Group
Agricultural wastes
Animal Husbandry
Animal Waste Management
Environment
Non-Point Source
43F
68D
13. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report)
Unclassified
21 . NO. OF PAC5FS
148
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
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DISCLAIMER
The information in this document has been funded wholly or in part by
the United States Environmental Protection Agency under assistance agreement
EPA-IAG-78-D-X0249 to the USDA-SEA-AR. It has been subject to the Agency's
peer and administrative review, and it has been approved for publication
as an EPA document. Mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
ii
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FOREWORD
EPA is charged by Congress to protect the Nation's land, air and water
systems. Under a mandate of national environmental laws focused on air and
water quality, solid waste management and the control of toxic substances,
pesticides, noise, and radiation, the Agency strives to formulate and imple-
ment actions which lead to a compatible balance between human activities and
the ability of natural systems to support and nurture life. In partial
response to these mandates, the Robert S. Kerr Environmental Research Lab-
oratory, Ada, Oklahoma, is charged with the mission to manage research
programs to investigate the nature, transport, fate, and management of
pollutants in ground water and to develop and demonstrate technologies for
treating wastewaters with soils and other natural systems; for controlling
pollution from irrigated crop and animal production agricultural activities;
for developing and demonstrating cost-effective land treatment systems for
the environmentally safe disposal of solid and hazardous wastes.
This project was initiated to evaluate the effects of summer grazing
cattle in the winter precipitation regions of the western intermountain
basins of the United States on the quality and quantity of nonpoint surface
runoff. Emphasis was placed on erosional, chemical, and bacteriological
characteristics of runoff from a typically managed summer pasture to deter-
mine the potential contribution of this practice to nonpoint source pollu-
tion. This information is useful in determining optimal practices which
will lead to the development of Best Management Practices (BMPs).
Clinton W. Hall, Director
Robert S. Kerr Environmental
Research Laboratory
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ABSTRACT
Streamflow water quality was intensively studied for three years
(1976-1979) on a grazed [21.5 hectares (ha)] and an ungrazed check (0.9 ha)
watershed near Potlatch, Idaho. The objective was to identify water quan-
tity, erosion, and water quality from a typical summer grazed watershed in
this region of winter precipitation and to identify animal impacts by com-
parison with the ungrazed watershed. Special emphasis was placed on bac-
teriological water quality measurements and interpretations.
The study period contained a near-drought year and two more nearly
normal years with significant runoff that provided good water quality deter-
minations. Erosion was minimal on the grazed watershed although cattle
trails were an obvious source. Chemicals from the grazed and ungrazed
watersheds were of low concentrations and quantities and the water quality
was not impaired for most uses. Indicator bacterial numbers were often high
and were closely related to cattle presence on the watershed. Unexpected
persistence of indicator bacteria was found after fall removal of the
livestock and significant numbers were found in the spring months after the
temperature raised and before grazing began. These results show that
bacterial quality is related to livestock, but there is considerable doubt
that indicator bacterial water quality standards developed for point sources
are appropriate for assessing non-point source bacterial contamination.
More research is needed to identify appropriate bacterial indicators for
nonpoint runoff. And research is needed to determine the effect of
alternative pasture and grazing management on runoff quantity and quality.
This report was submitted in fulfillment of EPA-IAG-D6-0030 and EPA-
IAG-78-D-X0249 by USDA-SEA-Agricultural Research under the sponsorship of
the U.S. Environmental Protection Agency. This report covers the period
June 1976 to December 1980, and the work was completed as of October 1980.
iv
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CONTENTS
Foreward i i i
Abstract iv
Figures vi
Tables viii
Abbreviations and Symbols x
Acknowledgment xii
1. Introduction 1
2. Conclusions 3
3. Recommendations 5
4. Study Objectives 6
5. Literature Review 7
6. Experimental Procedures and Methods • 10
Watershed description 11
Instrumentation 13
Watershed operation 14
Bacterial and chemical methods 15
Samples Analyzed 17
Nutrient discharge calculations 17
7. Results and Discussion 21
Hydrology and sediment 21
Water chemicals and oxygen 26
Water bacteria 28
Parameter response and spatial distribution 31
References 87
Appendices
A. Daily observed precipitation, runoff, and sediment
discharge 89
B. Daily climatic data 107
C. Sample and analytical procedures 120
D. Water quality data 129
v
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FIGURES
Number Page
1 Descriptive map of study watersheds topography, land
use, and instrumentation 12
2 Example sampling frequency during a typical hydrograph
and selected analyses on each sample 16
3 Observed watershed monthly precipitation and normal precipi-
tation (Potlatch, Idaho) 67
4- Accumulative daily precipitation and normal precipitation . . 68
5 Runoff season hydrologic summary for main watershed,
1976-77 69
6 Runoff season hydrologic summary for main watershed,
1977-78 70
7 Runoff season hydrologic summary for main watershed,
1978-79 71
8 Runoff hydrograph from the main study watershed 72
9 Runoff hydrograph from the check study watershed ...... 73
10 Soil moisture depletion from the grazed watershed 74
11 Rock Creek watershed groundwater levels, 1976-77 75
12 Rock Creek watershed groundwater levels, 1977-78 76
13 Rock Creek watershed groundwater levels, 1978-79 77
14 Water temperature and dissolved oxygen for the main
watershed 78
15 Water temperature and dissolved oxygen for the check
watershed 79
16 Streamflow hydrograph, fecal streptococci and coliform
concentrations, Rock Creek main watershed 80
vi
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Figures (Cont.)
Number Page
17 Streamflow hydrograph and specific conductivity,
Rock Creek main watershed, 81
18 Streamflow hydrograph and nitrate concentrations, Rock
Creek main watershed 82
19 Streamflow hydrograph and ortho-phosphate concentrations,
Rock Creek main watershed 83
20 Typical water quality parameter concentration response, COD,
to streamflow during snowmelt, Rock Creek main
watershed" 84
21 Typical water quality parameter response, total P, to
streamflow during a mixed snowmelt and rainfall event,
Rock Creek main watershed 85
22 Location and description of sampling sites within the
watershed 86
vi i
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TABLES
Number Page
1 Number of Samples by Source for Each of the Water Years
of the Project 18
2 Comparison of Actual Data and Interpolated Data Point
Integrations during October-December, 1977,
Rock Creek Main Watershed 20
3 Monthly Precipitation Data Summary 33
4 Annual Streamflow Summary „ 35
5 Runoff Event Summary 36
6 Annual Sediment Summary 39
7 Estimated Density and Coverage of Cattle Fecal Deposits on
the Rock Creek Watershed at Three Times during 1978 .... 40
8 Nitrogen and P Discharge from the Rock Creek Main
Watershed, 1977 Water Year 41
9 Nitrogen and P Discharge from the Rock Creek Check
Watershed, 1977 Water Year ..... 42
10 Nitrogen Discharge from the Rock Creek Main Watershed,
1978 Water Year 43
11 Nitrogen Discharge from the Rock Creek Check Watershed,
1978 Water Year 45
12 Nitrogen Discharge from the Rock Creek Main Watershed,
1979 Water Year 47
13 Nitrogen Discharge from the Rock Creek Check Watershed,
1979 Water Year 48
14 Phosphorus Discharge from the Rock Creek Main Watershed,
1978 Water Year 50
15 Phosphorus Discharge from the Rock Creek Check Watershed,
1978 Water Year 51
vi i i
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Tables (cont.)
Number Page
16 Phosphorus Discharge from the Rock Creek Main Watershed,
1979 Water Year • 52
17 Phosphorus Discharge from the Rock Creek Check Watershed,
1979 Water Year 53
18 Average Concentrations of FC, FS, and TC in Runoff from
the Rock Creek Main Watershed, 1977 Water Year 54
19 Average Concentrations of FC, FS, and TC in Runoff from
the Rock Creek Check Watershed, 1977 Water Year 55
20 Average Concentrations of FC, FS, and TC in Runoff from
the Rock Creek Main Watershed, 1978 Water Year 56
21 Average Concentrations of FC, FS, and TC in Runoff from
the Rock Creek Check Watershed, 1978 Water Year 57
22 Average Concentrations of FC, FS, and TC in Runoff from
the Rock Creek Main Watershed, 1979 Water Year 58
23 Average Concentrations of FC, FS, and TC in Runoff from
the Rock Creek Check Watershed, 1979 Water Year 59
24 Bacteriological Water Quality Standards 60
25 Water Quality Parameter Concentration Responses to
Streamflow 61
26 Average Percent Fecal Coverage in the Drainage Sampled
Within the Study Watershed, Nov. 4, 1978 62
27 Within Watershed Indicator Bacteria Results 63
28 Within Watershed N and P Results 65
ix
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r
ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
BOD
—
biological oxygen demand
Ca
—
calcium
CI
—
Chloride
COD
—
chemical oxygen demand
DIS
—
dissolved
DO
—
dissolved oxygen
EC
—
electrical conductivity
Exch
—
exchangeable
FC
—
fecal coliform
FS
—
fecal streptococci
FS/FC
—
fecal coliformrfecal streptotoccus ratio
K
—
potassium
Mg
—
magnesium
N
—,
ni trogen
Na
—
sodium
nh4-n
—,
ammonium nitrogen
N02-N
—
nitrite nitrogen
N03-N
—
nitrate nigrogen
Org
—
organic
P
—
phosphorus
P
—.
precipitation
PH
—
acidity level
Q
—
runoff
Sed
—
sediment
SC
—
specific conductivity
TC
—
total coliforms
TKN
—
total kjeldahl nitrogen
TOC
—
total organic carbon
T-N
—
total nitrogen
UNITS OF MEASURE
a — acre
cm — centimeter
g — grams
ha — hectare
in — inch
kg — kilogram
km — kilometer
1 — 1i ters
m — meters
x
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SECTION 1
INTRODUCTION
In this age of environmental awareness and increased population den-
sity, it is urgent to define and improve stream water quality if streams
are to continue to be a source of beauty, recreation, and water supply.
Streamflow which emanates as surface runoff from agriculture pastureland is
suspected of having less than desired quality because of the obvious
possibility of fecal, chemical, and sediment contamination. Cattle grazing
occupies a significant portion of the agricultural landscape in much of the
nation, with cattle densities ranging from feedlots to many hectares (ha)
per animal on the western desert ranges. Management for protection of
soil, vegetation, and water resources ranges from (a) total sacrifice and
disregard to (b) normal protection for continuous economic production to
(c) near disuse or major conservation efforts.
The effect of cattle grazing on downstream water quality with various
management schemes is currently very poorly defined. Scientific judgment
would indicate that the water quality and flow rates, erosion and sediment
production, chemicals, and bacteria could all be altered by the presence of
livestock on a watershed and the management practices associated with this
agricultural operation. However, there is no method of predicting these
effects other than through experimental data obtained by scientific study.
These results, when combined with those of related studies, will provide
inferences of cause and effects.
The result of not obtaining the environmental impact knowledge of
agricultural production operations such as cattle grazing could be poten-
tially devastating should regulations and controls be mandated without
scientific basis. Even the uninitiated recognize the fact that every
operation on agricultural land will have some environmental and downstream
impact, and changes and demands for restrictions and controls are
inevitable. It is imperative that scientific facts and documented
alternatives be available so that society can make intelligent choices on
what controls, if any, are necessary.
This study was conducted to evaluate the effects of cattle grazing on
runoff volumes and rates, erosion and sedimentation, and chemical and
indicator bacteria concentrations and quantities in the surface runoff
discharged from agricultural watersheds in the principle grazing areas of
the Pacific Northwest. The purpose of this study was to document these
water quantity and quality variables over a period of three years from a
small watershed managed in a typical fashion for this region under
sustained economic production without obvious resource abuse. The impact
1
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of cattle presence was defined by excluding grazing on a smaller, but
otherwise similar, grazed watershed. The effects of management
alternatives were not evaluated. Although a wide variety of water quality
parameters were measured on the analyzed samples (approximately 23 types of
determinations), special emphasis was given to the bacterial analyses
because the animal presence was expected to have more effect on these than
on any other parameter.
Thfs study of agricultural runoff water quality was one of four simi-
lar studies cooperatively sponsored by the US-EPA. The other three were
located in Ohio, Oklahoma, and Nebraska. Each study location measured
water quality from grazed pastureland, but each had different emphasis
depending upon the staff and facilities available. This study differed
most distinctly from the others by the fact that the study investigated the
opposing summer grazing-winter runoff combination.
The report which follows is a summary description of the study objec-
tives; facilities and instrumentation used; data organized by hydrology,
sedimentation, and water quality; and interpretations and conclusions.
Although much detail is omitted, the summaries in the text and appendices
provide sufficient information so that the reader may review the data to
substantiate the conclusions or to develop their own. This opportunity for
re-interpretation is important because the implication of these findings
may likely change in the future, but the carefully documented facts of
these observations will remain permanent.
2
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SECTION 2
CONCLUSIONS
HYDROLOGY AND SEDIMENT
The three study years encompassed a variety of precipitation amounts
and event types from near drought to a near normal snow pack. The mean
precipitation quantity for the study period was slightly below the long-term
average, but in general the data are quite representative for the study
region and certainly will apply throughout a broad region of the west where
winter precipitation and summer grazing dominate.
Surface runoff, whose quality was the object of this study, were 199
and 136 millemeters (mm) of the 676 and 516 mm (near normal) of precipita-
tion for the main watershed for the two near-normal years, or about 20 per-
cent of the precipitation. The quantity from the small, upland check water-
shed was only one-third of this amount. The important feature was that
adequate surface runoff occurred from both the main and check watersheds and
that the water quality of both areas was well defined. Because of the dif-
ference in size and topographic setting, significant natural differences in
runoff volume was expected and no attempt was planned or conducted to relate
runoff quantities to watershed treatments of livestock grazing.
Erosion and streamflow sediment were much less from these pasture lands
than from similar tilled agricultural lands. Average sediment yields were
only 382 kilograms per hectare per year (kg/ha/yr) from the main watershed
for the study period compared with an average of 5,900 kg/ha/yr for a typi-
cal nearby tilled watershed during a study period of 1961-65. But the check
watershed averaged only 19 kg/ha/yr for the study period, thus it showed
much less erosion and sediment transport than the main watershed. Part of
this reduced sediment from the check watershed was obviously associated with
the reduced surface runoff, but beyond that the observations showed that
cattle trails and trampling within the main watershed contributed to the
amount of sediment. Several trails on the broad main watershed slopes be-
came small interceptor ditches from surface flow upslope and eroded several
centimeters (cm) in depth and width. Several shorter trails within the
stream alluvium leading to water places eroded even more. And the small
stream banks (most less than 25 cm) had some deterioration due to trampling
during grazing and watering. No quantitative assessment was made of these
cattle effects and they appeared to be not highly significant to the overall
water quality, although this is certainly a quality aspect that could be
altered by management techniques of controlled cattle traffic.
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INDICATOR BACTERIA AND NUTRIENTS
Total coliforms (TC) in runoff from grazed and ungrazed areas in the
Pacific Northwest did not correlate with the presence or absence of
animals. Fecal coliform (FC) and fecal streptococcal (FS) numbers were
elevated in runoff from the grazed area when cattle were present above that
when they were absent. However, even after animals were absent from the
area for several months, FC numbers were elevated in the runoff above
recommended levels of 200/100 ml (FC) and 1,000/100 ml (TC) for primary
contact. In fact, FC and FS numbers appeared to increase from less than
100/100 ml to several thousand per 100 ml in the runoff from the grazed area
for several months in the spring during warm, wet weather after animals were
removed the previous fall. Almost three years of cattle absence were
required for FC numbers in runoff from the check watershed to be
consistently below the maximum recommended numbers for primary contact. The
data indicate that the use of conventional FC/FS ratios or FC numbers in
runoff as a measurement of recent fecal pollution by cattle on a grazed area
is of limited or no value. FC/FS ratios of 1, which indicate recent animal
fecal pollution, were found after animals had been removed for several
months.
Nitrogen (N) and phosphorus (P) deliveries from the watersheds were
low—generally much lower than from areas used for other agricultural pur-
poses. Total-N losses from the grazed area were 3.8 and 3.8 kg/ha during
water years 1978 and 1979, respectively, while total-P losses during the
same periods were 1.29 and 0.93 kg/ha, respectively, with very low losses of
ortho-P. More N fell on the grazed watershed in precipitation than was lost
in the runoff.
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SECTION 3
RECOMMENDATIONS
This research project provided hydrologic, erosion, and water
quality information from a specific site, with one management level, and
for minimal study years. While these baseline data are extremely useful
for general recommendations that water quality is quite good from pasture
land of moderate grazing and management, additional research must be con-
ducted to determine the effect of management practices on sediment,
chemical, and bacteriological water quality parameters and to establish
bacterial water quality standards for non-point sources. Only through
carefully planned and documented studies with varying management levels
and techniques will it be possible to adequately understand the effect of
management options on local and downstream water quality.
Research is desperately needed to determine the meaning of FC and FS
numbers in runoff from nonpoint sources such as grazed areas. This study
indicated that these organisms multiplied on the pasture during warm, wet
weather several months after the animals were removed. Voluminous liter-
ature indicates that pathogenic microorganisms, which the presence of
these organisms indicates, cannot survive for long periods outside the
warm-blooded host. While the numbers of FC and TC in runoff exceeded
those recommended for primary contact, the situation on the watershed
should not present a health hazard. Fecal coliform and TC numbers in
runoff as defined for point sources do not appear to be viable water
quality criteria for non-point sources.
Chemicals such as N and P in runoff from those areas were below
levels that would usually be of environmental concern. Grazing areas in
the Pacific Northwest, managed as the area described in this report,
should not present chemical environmental hazards. Future studies should
concentrate on bacteriological processes and interpretations for poten-
tial health and environmental hazards.
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SECTION 4
STUDY OBJECTIVES
This study was conducted to evaluate the effects of cattle grazing on
runoff volumes and rates, erosion and sedimentation, and chemical and bac-
teria concentrations and quantities in the surface runoff discharged from
agricultural watersheds in the principle grazing areas of the Pacific
Northwest. The purpose of this study was to document these water quantity
and quality variables over a period of three years from a small watershed
managed in a typical fashion for this region under sustained economic pro-
duction without obvious resource abuse. The effects of management alterna-
tives were not evaluated but the impact of cattle presence was defined by
excluding grazing on a smaller, but otherwise similar, grazed watershed.
Although a wide variety of water quality parameters were measured on the
analyzed samples (approximately 23 types of determinations), special
emphasis was given to the bacterial analyses because the animal presence
was expected to have more effect on these than on any other parameter.
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SECTION 5
LITERATURE REVIEW
The effect of cattle grazing on receiving stream water quality has
been a subject of some concern. While research in this area has been
limited, some studies have addressed this pressing need. There have been
related studies of runoff water quality from native prairie and forested
areas and studies on the effect of fertilization of grasslands on runoff
water quality. However, most of these studies were conducted in areas with
a summer rainfall climate.
Timmons and Holt (1977) found that average annual total-N and total-P
losses from a native prairie in the upper midwest were 0.8 and 0.1 kg/ha,
respectively. In North Carolina, Kilmer et al. (1974) studied nutrient
losses from two small steep grassed watersheds fertilized with a total of
either 112-48-24 or 448-192-24 kg/ha of N-P-K, respectively. They found
annual total-N losses in the runoff were 3.28 and 12.08 kg/ha and that P
losses were 0.15 and 0.27 kg/ha, respectively, for the low and high fer-
tilizer rates. Timmons et al. (1977) measured total N and P losses in
runoff from an aspen birch forest watershed and found that annual N losses
ranged from 1.13 to 2.12 kg/ha while total-P losses ranged from 0.13 to
0.30 kg/ha with ortho-P and organic-P being almost equal. These studies
showed that N and P losses in runoff were low in runoff from grasslands and
forests; and while fertilization may have increased these losses somewhat,
moderate fertilization did not cause large increases in nutrient losses in
runoff. From a diverse use watershed located in the Georgia Coastal Plain,
Asmussen et al. (1979) found NO3 plus NO2-N and ortho-P losses ranged
from 0.14 to 0.24 and 0.141 to 0.144 kg/ha/yr, respectively.
The studies that have reported on nutrient losses in runoff from
grazed watersheds generally report that the effects of grazing on water
quality are minimal. Thomas and Crutchfield (1974) studied several agri-
cultural watersheds and found that the highest nitrate-nitrogen (NO3-N)
concentrations were in runoff from a watershed that was 98 percent pas-
ture. However, the highest NO3-N concentrations they measured were
6 ppm. P levels were low and P concentrations correlated with the geology
of the area from which the runoff originated while NO3-N levels corre-
lated with land use. Chichester et al. (1979) studied nutrient losses in
runoff from grazed and winter feeding areas in Ohio and concluded that
chemicals in runoff from those areas did not exceed water quality stan-
dards. In Oklahoma, Olness et al. (1975) examined runoff quality from
rotational grazed and continuously grazed watersheds and found that annual
N loads from the management systems were 1.59 and 7.87 kg/ha, respectively,
7
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while P was 1.27 and 4.6 kg/ha, respectively, while Menzel et al. (1978)
reported similar data for this area. The more intensive grazing caused
greater N and P losses. These N contributions would not seem excessive
when one considers that Olson et al. (1973) found that N in the rainfall
was 5.6 to 15.7 kg/ha/yr going from west to east in Nebraska, and Schuman
and Burwell (1974) reported the annual N delivery in rainfall in western
Iowa was 7.26 kg/ha.
The effect of cattle grazing on runoff water quality has received
limited attention. Kunkle (1970) compared TC and FC contributions from a
grazed pasture and a hay field in Vermont. He found that cattle grazing
contributed FC to the runoff and concluded that FC were better indicators
of animal pollution than TC. FC counts from the ungrazed hay field that he
studied ranged up to 1,000 organisms/100 millileters (ml). In 1976,
Buckhouse and Gifford simulated rain on small grazed and ungrazed runoff
plots. They found no significant differences between numbers of fecal
indicator bacteria in the runoff from the grazed and ungrazed plots. They
did show that FC survived in a "cowpie" beyond 18 weeks. Stephenson and
Street (1978) studied the effect of cattle grazing on stream-water quality
in: southern Idaho and found maximum FC counts soon after the introduction
of cattle. At several sites, stream FC counts increased from 0 to 2,500
organisms/100 ml. After cattle were removed, the FC counts in the stream
remained high for several weeks to three months. They also found that TC
numbers correlated poorly with FC numbers. Generally, runoff from a
cattle-grazed area, when compared with an ungrazed area, will show
increased sediment and numbers of indicator bacteria (Milne, 1976; Robbins
et. al., 1972). Robbins et al., (1972) compared FC counts in runoff from a
grazed: and ungrazed watershed in North Carolina and found that the two
averaged 30,000 and 10,000 organisms/100 ml, respectively. Schepers (1980)
monitored water quality from a large, diverse-use watershed and noted that
the: majority of the runoff and baseflow water samples exceeded FC standards
for recreational water quality. They concluded that it may be
inappropriate to use FC numbers as a parameter for nonpoint source water
quality, but the FC/FS ratios were less than one most of the time,
indicating the source was nonhuman.
Doran and Linn (1979) conducted a comprehensive three-year study in
Nebraska on the effect that grazing animals have on fecal bacteria in run-
off water. They found that FC bacteria in the runoff assessed grazing im-
pact and that bacteriological indicator counts in runoff from the grazed
and ungrazed areas generally exceeded recommended water quality standards.
They concluded that recommended water quality standards for a point source
may not be definitive for a nonpoint source. In their study, FC numbers
were five to ten times higher in runoff from the grazed area than from the
nongrazed area and the FC/FS ratio was 11 times that of the nongrazed area.
There are some useful data on the effect of the environment and
persistence of indicator bacteria and organisms classified as fecal
streptococci. Van Donsel et al. (1967) found the 90 percent reduction time
for FC in soil was 3.3 days in summer and 13.4 days in autumn while the FS
8
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90 percent reduction time was 2.7 days in summer and 20.1 in winter. They
found evidence of aftergrowth of nonfecal coliforms in the soil. Other
results were presented showing that some enteric bacteria can grow in an
environment approximating that of a clear mountain spring (Hendricks and
Morrison, 1967). Kibbey et al. (1978) found cool, moist conditions
prolonged the survival of Streptococcus faecal is in soil for at least
12 weeks. In another study, Stephenson and Rycert (1981) found stream
sediments in southwestern Idaho could contain large quantities of E. coli.
They found stream sediments contained 2 to 760 times more E. coli than the
overlying water. They also found that more than 80 percent of atypical
colonies growing on an FC medium tested positive as E. coli (Rycert and
Stephenson, 1981). They pointed out the potential for significant errors
if these organisms are disregarded.
Geldreich (1976) presented a classic discussion on the behavior of
indicator organisms, and obtainment and use of FC and FS data. He con-
cluded that FC/FS ratios of 4/1 or higher show human fecal contamination
while other warm-blooded animal fecal contamination shows FC/FS ratios of
0.6 or less. As sample storage is prolonged or as the contamination moves
downstream, the FC/FS ratio will increase from 0.7 to 3.0 because S.- bovis
and equinus die off rapidly in samples containing fecal contamination
from nonhuman sources. He noted that S_. faecal is var. 1 iquifaciens should
be considered ubiquitous as it can exist for extended periods in soil,
irrigation water, and other waters below 12° C and concluded that FC/FS
ratios using FS numbers below 100 are probably useless. He also cited
examples that FS can be routinely isolated from vegetation. Later,
Geldreich (1981) questioned the use of TC in water-quality studies.
Skinner et al. (1974) questioned the use of the FC/FS ratio for nonpoint
source studies; however, the numbers of FC and FS they found were generally
low.
The existing data are sketchy on the effect of cattle grazing on
runoff water quality, and few studies have followed bacterial and chemical
quality of runoff from these nonpoint sources on a year-round definitive
basis, especially in a summer-grazed winter rainfall climate area. The
purpose of this 3-year study was to determine the effect of grazing on
runoff water quality in a winter rainfall climate.
9
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SECTION 6
EXPERIMENTAL PROCEDURES AND METHODS
A paired watershed design was selected to study the water quality impact
of animal grazing. The main watershed with an area of 21.5 ha [53.1 acres
(a)] was summer grazed with management typical of this region. A check
watershed of 0.9 ha (2.2 a) adjacent to the main watershed and a part of the
original pasture was fenced to exclude all cattle. These two watersheds
were intensively instrumented for complete hydrologic, sediment, and water
quality measurements, and were continuously monitored for the period
December, 1976 to July, 1979.
The watersheds were carefully selected to be generally representative of
the partially forested grazing areas of the Pacific Northwest. The level of
recent and current management was of particular interest because management
was not to be varied but was to be typical (i.e. most representative) such
that neither the worst nor best case was represented. The areas studied met
these criteria.
The pasture was grazed at a rate that fully utilized the grass produc-
tion which produced overgrazing in dryer years but yet not beyond sustained
use over a period of years. Little management for grazing distribution or
to prevent cattle contact with the stream was done, but this is typical for
this region of open pasture, summer grazing. The cattle were usually re-
moved in late October and returned to the pasture in late May. The actual
watershed management was carefully recorded and monitored through cattle
numbers, forage production and utilization, cattle habits and movements, and
dung distribution.
The small check watershed was fenced at the outset of the study and
grazing was prohibited during the remainder of the study other than an oc-
casional deer and a calf that broke in for one day during the first summer.
No attempt was made to remove existing manure at the study initiation, thus
the animal effects were a decaying function from their last presence in
October, 1976. To approximately maintain the grass quantities similar be-
tween the two watersheds and keep the presence of cattle as the only major
difference, the check area grass was mowed, baled, and removed about mid-
summer each year, after most vegetative growth had occurred.
10
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WATERSHED DESCRIPTION
The main and check watersheds are shown by the planimetric map of
Figure 1. The watersheds are located in northern Idaho, 6.4 kilometers (km)
[4 miles (mi)] due south of Potlatch, Idaho, which is 26 km (16 mi) north-
northwest of Moscow, Idaho. The fence corner shown in the lower right of
Figure 1 is near the south-east corner of Section 25, Range 5 West, Township
41 North. The watersheds are in the upper reaches of the Rock Creek drain-
age which is a tributary of the Palouse River with confluence near Potlatch,
ID.
The climatic setting is typical of the mountain foothills throughout
much of the west. Average annual precipitation at the study site is approx-
imately 635 mm [25 inches (in)]. There is significant variation in average
precipitation amount and form across the region due to elevation and loca-
tion. The annual precipitation distribution shows that most precipitation
occurs in the winter months, November to April, in the typical western Medi-
terranean type climate. This has significant implications to this study
where the cattle were present during the dry summer season when surface run-
off seldom occured. Additional climate data are provided in subsequent sec-
tions.
The watershed topography is mildly sloping (4 to 8 percent) in the mid-
and lower portion and steep (15 to 25 percent) in the upper wooded region.
The check watershed is all mildly sloping and all open grassland. The
drainage pattern and watershed boundaries are well defined throughout except
on the north-east boundary of the main watershed and southern boundary of
the check area where the gently changing slopes caused some minor definition
difficulty.
The watersheds typify the transition region between the nearly complete
farmlands and arid grasslands at the lower elevations to complete forests in
the higher elevations. The main watershed open pasture area had been
cleared from forest in the early part of this century and farmed a number of
years, probably largely in winter wheat. In 1968, this field was reseeded
to pasture grasses and has since remained in continuous summer pasture with
the same ownership and manager. The check watershed represents the same
conversion from farming to pasture. The woodland pasture area in the upper
main watershed is moderate dense fir and pine timber and brush which has had
some timber removed over the years (none recently) and provides very little
grazing.
The watersheds are within a 65 ha (160 a) pasture which is primarily in
timber and brush to which the cattle had access. The main watershed area of
21.5 ha (53.1 a) is composed of 12.3 ha (30.4 a) open pasture, 9.2 ha (22.7
a) woodland pasture and 2.2 ha (5.4 a) logged pasture. The ungrazed check
watershed of 0.9 ha (2.2 a) is all open pasture, but of course was not
grazed. Fecal analysis and time-and-movement observations indicate that the
cattle obtained 50 to 60 percent of their annual grazing on the main water-
shed. The logged pasture in the lower left of Figure 1 was owned by the
adjacent rancher. All large timber had been removed, which left the area in
11
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MAIN
WATERSHED
(21.5 ho)
Station
Spring
Woodland
Posture
Logged Pasture^
«ATC»SHCO
/LOCATION
f Ralngagt
A Soil Moltture
¦ Groundwater
¦ Streomgoge
-920- Contour, motere
— — Woterthed Boundory
»—* Fence
Intermittent Stream
— Field Boundory
C:i3 Small Pond
/Or CHECK
' I WATERSHED
(0.9 ha)
Seato, otctvre
gure 1. Descriptive map of study watersheds topography, land use, and
i nstrumentation.
12
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brush, stumps and slash, and small grass patches. The area was used for
horse pasture sporadically throughout the year. This area produced only
minimal streamflow as observed near the fence boundary and the researchers
believe it had minimal influence on the water quality at the main watershed
grazing site because of its small size and distance from the main gaging
wei r.
The watershed soils are composed of about 100 to 125 cm (40 to 50 in.)
of silt loam loess overlying decomposed granitic bedrock. The Taney series
occupies the flatter areas north of the main watershed drainage and the very
upper ridge area on the west boundary. The Santa series is on the midslope
section and all of the check watershed area. The Stanford series is an
alluvium of loess derivation and formed a narrow strip along the main water-
shed drainage up to the woodland pasture. Santa (frigid typic Fragio-
chrepts) and Taney (frigid boralfic Argixerolls) are very similar and as
mapped on the study watershed are generally 60 to 70 cm (24 to 28 in.) of
silt loam underlain by silty clay loam to a depth of 107 to 122 cm (42 to
48 in.) where decomposed granitic bedrock begins and progressively becomes
less decomposed and more massive with depth.
The loess has good water holding capacity and is moderately well
drained. The entire loess mantle is usually recharged to field capacity by
winter rains and deep percolation into the bedrock causes local perched
water tables, springs, and continuous seepage flow in the main watershed
channel during the spring and early summer months. The check watershed had
very little evidence of this effect other than some wet zones in the lowest
swales. Soil moisture was generally adequate until mid-summer when the
shallow rootzone approached the wilting point (see report section on soil
moisture). The soil fertility level is marginal and showed significant re-
sponse to moderate rates of applied fertilizer.
The pasture vegetation was composed largely of brome, fescue, and blue-
grass. Grass production was measured in 1978, a near normal precipitation
year. The main watershed was separated into a north and south unit at the
principal channel. The north unit produced 6,400 kg/ha and the south unit
only 2,400 kg/ha, as determined by small, random exclosures. Grazing utili-
zation was approximately 60 and 80 percent, respectively, for this particu-
lar year.
INSTRUMENTATION
The principle instrumentation installed on the watershed is shown in
Figure 1. Precipitation was measured with five gages. A propane-heated
tipping-bucket gage with an adjacent non-recording standard gage were
located at the weather station and on the check watershed. A mechanical
recording gage was located in the upper (west) portion of the main water-
shed. The recording and tipping-bucket gages were snow-shield equipped.
Runoff on the main watershed was measured with a 2:1 broad-crested v-notch
weir formed from aluminum, and water levels were measured with a mechanical
strip-chart recorder. The check watershed weir was a small scale SCOV-weir
13
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(complex shape and laboratory calibrated) formed of metal, and water levels
were measured with two mechanical strip-chart recorders. Both weirs were
volumetrically calibrated over the measurement range where nearly all flow
occurred and agreement was close to published calibrations.
Both runoff weirs were covered with an instrument house with the weir
accessible through a floor trap door. Both the house and weir were heated
for winter operation. A Federal Interagency PS-69 pumping sampler was
installed in both instrument houses to automatically obtain dual samples at
preprogrammed intervals (hourly during surface runoff, twice each day for
base flow). One sample was for sediment analysis, the other was for chemi-
cal and bacterial analysis. Those pumping samplers were modified to provide
a complete system of flushing using current stream water (no backflush tank)
to minimize contamination between samples or foreign quality water and to
have minimal disturbances to the stream. The sample intakes were attached
to the upstream weir face. Dual samplings obtained by the PS-69 sampler and
by direct hand sampling showed essentially identical chemical and bacterial
results.
Additional instrumentation to complete the hydrologic and climatic data
regions included neutron soil moisture access tubes at nine sites as shown
in Figure 1, six groundwater wells in the stream alluvium, and a complete
weather station. The weather station included air temperature and humidity,
wind travel and direction (3-m height), soil temperature profile, pan evapo-
ration with anemometor, solar radiation, soil frost tubes, and the two rain-
gages. All meteorologic instruments (except the evaporation pan), both tip-
ping bucket raingages, both weir water levels, and stream water temperature
gages were all recorded on an electronic data logger.
WATERSHED OPERATION
All watershed instruments were operated continuously and sampling was on
a regular frequency from December, 1976 to July, 1979. During the summer
months (about May 1 to October 30), approximately 45 to 55 cows with calves
grazed the pasture containing the main watershed. Specific details of the
forage production, grazing, and fecal distribution were monitored by range
scientists and are reported in a subsequent section. Many auxiliary
measurements were made at various times such as snow depths, infiltration
rates, flow rates and water samples at other locations in the watersheds,
decomposition, and fecal bacteria, etc. Although many of these are not
reported or summarized in this report, they provided necessary insight for
the interpretations and conclusions which follow.
Essentially all watershed management decisions were left to the rancher
to continue in a fashion similar to previous years. Cattle were brought to
and removed from the pasture according to grass and weather conditions. The
watershed pasture areas were fertilized in the spring of 1977 and 1978, with
62 and 78 kg/ha [55 and 70 pounds (lbs)/a] of N, respectively. No fertili-
zer had been applied in recent years but moderate application amounts are a
common practice by area ranchers. Some supplemental water and feed was
14
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supplied to the cattle in the late summer months, but these operations were
small and likely had no effect on any of the study measurements.
Cattle grazing was by 44 and 58 animal units during the 1977 and 1978
summer periods, respectively. Primarily, these were cow and calf combi-
nations with about 10 to 15 yearlings. Because of the drought in 1977, some
cattle were removed before the end of the grazing season. Cattle numbers
remained constant in 1978.
The grazing habits of the cattle were recorded visually and by diet
analyses of fecal samples. Preliminary results showed that nearly all
grazing was on the watershed in the early summer. By midsummer, approxi-
mately 40 percent was from the woodland species; and by late summer, when
the watershed grasses had matured, approximately 60 percent was from the
woodlands. This pattern had some impl ication.s to the manure deposition, but
loafing and water habits also played a significant role.
BACTERIAL AND CHEMICAL METHODS
When stream flow increased above baseflow on the main grazed water-
shed, water samples were collected automatically on an hourly basis during
the event. Baseflow samples were obtained at least twice daily. There was
no baseflow on the check watershed; samples were collected automatically on
an hourly basis when significant runoff occurred.
Water samples analyzed for an event consisted of the hourly samples
obtained on the rise and peak with sufficient samples being analyzed on the
recession for event characterization . The water samples were held at 4 C
before analysis; analyses for bacterial content were conducted in less than
24 hours after sampling. All analyses were conducted according to stan-
dard techniques. Analytical and sample handling procedures are shown in
Appendix C.
All runoff and baseflow samples were analyzed for TC, FS, FC, NOj-N,
dissolved ammonium (NH|), ortho-P, specific conductivity (SC), chlo- /
rides (CI-)), total organic carbon (TOC), chemical oxygen demand (COD),
pH, and dissolved oxygen (DO). Many of the samples were examined for total
Kjeldahl-N, total-soluble Kjeldahl-N, total hydrolyzable-P, total soluble
hydrolyzable-P, total-P, total dissolved-P, biochemical oxygen demand
(BOD), sodium (Na), potassium (K), calcium (Ca), and magnesium (Mg). Sedi-
ment P, organic P exchangeable sediment NH^, organic N and sediment
(SED)-N were calculated.
Groundwater sampling wells, 4-cm inside diameter, were established at
six locations in the main watershed (Figure 1). At selected times during
the year, about one liter of water was pumped from the wells and discarded,
they were allowed to refill, and water samples were obtained. The samples
were analyzed for NO3-N, NH|-N, total Kjeldahl-N, ortho-P, total-P, TOC,
COD, pH, EC, Cl~, Mg, Ca, Na, and K.
15
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r~
cr>
(/)
2
o
>4—
E
o
-------
At the initiation and termination of the study, soil cores were ob-
tained from ten selected areas within the watershed to determine any soil
chemical changes that occurred during this study. The soil sampling sites
are shown as the soil moisture sites in Figure 1. One sampling site
between the spring and streamgage site is not shown in Figure 1. The soil
cores were taken to depths of 180 cm (or bedrock) at 15-cm increments.
Soil moisture, NO3-N, NH^-N, and ortho-P were determined on these
samples.
Precipitation samples were collected in 10 x 10 cm plastic freezer con-
tainers mounted on top of a post which was 1-1/2 m high. The containers
were changed often to avoid contamination. The precipitation samples were
analyzed for NO3-N, NHzf-N, pH, and if sample volumes were adequate,
for total Kjeldahl-N. In the spring and summer, some precipitation samples
were discarded because of contamination by bird manure.
SAMPLES ANALYZED
The water quality and sediment samples were obtained by both pumping
samplers and hand collection. Many more samples were collected than needed,
then a series of samples were selected for analysis based on the hydrograph
development to provide adequate coverage. Table 1 provides a summary of
samples analyzed.
During the first water-year (1977) of this study (December 21, 1976
through September 30, 1977), a total of 461 water quality samples and 411
sediment samples were analyzed, as this was a near drought year. Although
the watershed was not fully instrumented for sampling until December 21,
1976, the fall was very dry and two insignificant events were missed. For
water-year 1978 (October 1, 1977 through September 30, 1978; precipitation
close to normal), a total of 927 water quality samples and 1128 sediment
samples were analyzed. During water-year 1979 (October 1, 1978 through July
1, 1979; precipitation slightly below normal), a total of 687 water quality
samples and 870 sediment samples were analyzed. While the 1979 water-year
was terminated July 1, 1979, no events were missed because there was
inadequate precipitation for runoff to occur from the watershed during the
remainder of water year 1979.
Because most of the precipitation in the Pacific Northwest occurs in
late fall, winter, and early spring, during the three years of the study,
only 22 of the 1,447 runoff samples analyzed from the grazed watershed were
obtained while cattle were present in the spring, summer, and early fall.
The source of the water samples analyzed during the three-year study period
are shown in Table 1.
NUTRIENT DISHCARGE CALCULATIONS
Two methods of numerical integration of streamflow with chemical
concentrations were tested. The first method involved graphing the
17
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TABLE 1. NUMBER OF SAMPLES BY SOURCE FOR EACH OF THE WATER YEARS
OF THE PROJECT
Sample source
Grazed Ungrazed
Water (main) (Check) Precipi- Within Ground-
year watershed watershed tation watershed water
Number of water quality samples obtained from each area
1977 356 41 48 — 16
1978 627 162 75 24 39
1979 464 121 46 24 32
Number of sediment samples obtained from each area
1977 368 41 - 2 -
1978 898 205 25
1979 662 160 49
18
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hydrograph, which was previously defined by straight-line segments from the
continuous stage record, and plotting the chemical concentrations on the
same graph. Then a curve was sketched which best defined a continuous
concentration curve for the duration of the hydrograph, points read from
this detailed concentration graph to provide adequate straight-line
interpolation throughout, and integration performed by multiplying computed
water volumes between concentration midpoint intervals times the point
concentration. This graphing and re-entry of concentrations was a laborous
process.
With frequent streamflow sampling (hourly during significant flow
rates), it was found that the concentrations at the sampling times provided
a good approximation of the time description of the concentration graph. As
a result, an integration using the same integration techniques but only
those concentrations at sample times, i.e., actual data, were compared with
the more detailed interpolating integration method. A sample hydrograph is
shown in Figure 2 to demonstrate typical sampling frequency and the analyses
made on each sample. From the results shown in Table 2, it was concluded
that the two methods provided very similar discharge quantities and average
concentrations, thus the actual data concentrations were integrated
throughout the study data.
19
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TABLE 2. COMPARISON OF ACTUAL DATA AND INTERPOLATED DATA POINT INTEGRA-
TIONS DURING OCTOBER-DECEMBER, 1977, ROCK CREEK MAIN
WATERSHED
Actual
data
Interpolated data
Parameter
Quantity
Avg. conc.
Quant i ty
Avg. conc.
(kg)
(mg/1)
(kg)
(mg/1)
NOt-N
2.5
0.34
2.4
0.33
NHJ-N
0.2
0.03
0.2
0.03
Soluble Org.-N
8.3
1.1
7.4
1.0
Soluble TKN
8.5
1.2
9.5
1.3
Soluble Total-N
11.1
1.5
10.6
1.4
Total Org.-N
53.2
7.2
50.4
6.8
TKN
53.5
7.3
50.4
6.8
Total-N
56.0
7.5
59.5
8.1
Sediment N
44.8
6.1
41.4
3.6
Ortho-POzf^
1.8
0.25
1.8
0.25
Soluble Org.-P
0.5
0.07
0.5
0.06
Soluble Total-P
2.6
0.36
2.4
0.33
Total Org.-P
43.9
5.9
11.1
1.5
Total-P
21.5
2.9
22.4
3.0
Sediment P
18.9
2.6
22.0
3.0
TOC
115.0
15.5
115.0
15.6
COD
427.0
58.0
417.0
57.0
BOD
14.0
1.9
14.0
1.9
ci-
3.9
0.52
4.1
0.56
Na
33.9
4.6
34.6
4.7
Ca
26.8
3.6
24.9
3.4
Ma
8.9
1.2
9.2
1.3
k"
23.4
3.2
22.8
3.1
20
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SECTION 7
RESULTS AND DISCUSSION
HYDROLOGY AND SEDIMENT
To adequately research the water quality emanating from a given water-
shed, considerable effort must be included toward measuring and defining the
causative hydrology of the study watershed if the results are to be fully
interpreted, put into perspective compared to long time expected climate,
and appropriately transferred to other sites having different characteris-
tics. As a result, continuous measurements were obtained for the principle
hydrologic components of precipitation, streamflow at the gaging sites, and
climatic variables. Frequent sampling of other hydrologic components such
as soil moisture, groundwater levels, and pan evaporation provided an inten-
sive scenario of the watershed hydrology during the study period.
Sediment is the most common, and often the most degrading, water quality
parameter. It is very closely allied with surface hydrology through land
use and surface runoff, and as such, it is common to consider sediment and
hydrology together. However, in a study such as this, where water quality
is the major emphasis, sediment plays an extended role because many of the
chemical and biological water quality parameters are transported by and are
an integral part of the sediment.
Daily quantitities of precipitation, streamflow, and sediment measured
on the main and check watersheds are tablulated in Appendix A. Each of
these daily values is the integral of the measured rates of precipitation
and discharge which were tabulated on very short time intervals depending
upon the rate of change. Examples of these detailed values will be given,
but their large volume precludes publishing more than the daily and longer
period accumulations. A brief discussion of each major data set follows to
provide more specific examples and interpretation.
Precipitation
For the three study years, precipitation ranged from near drought during
the 1976-77 winter to above normal for 1977-78, and near normal for
1978-79. The monthly values for these years are shown in Figure 3, along
with the normal amount based on a 30-year record at Potlatch, Idaho (6.4 Km
due north and 120 m less elevation). Normal precipitation at the study site
would likely be nearly equal to that at Potlatch, ID.
21
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Daily accumulative precipitation is presented in Figure 4, which
clearly shows the three years with respect to normal and each other. Data
from the Potlatch gage were substituted for the period prior to the begin-
ning of data taking at the site in December 1976. Table 3 provides a
monthly summary of precipitation measured by each gage and the nearby
weather bureau gages at Potlatch and Moscow, ID. It was noted early in the
study that low intensity precipitation falling into the propane heated tip-
ping bucket gages registered significantly less than the adjacent gages
because of evaporation from the heated gage bucket. As a result, these
tipping bucket data were inaccurate during winter months when the heater
was used and were, therefore, omitted.
Precipitation during the three study years averaged 65 mm (2.6 in)
below the Potlatch normal of 622 mm (24.5 in). The first year was a severe
regional drought with very limited snow cover at any time and only 370 mm
(14.6 in) on the watershed. The two subsequent years were more nearly nor-
mal, but neither of these years had a large snowpack accumulation because
of mid-winter thaws. February 1979 had the largest accumulation of snow
depth (about 45 cm) as shown in Figures 5, 6 and 7, and this melt provided
the largest surface runoff measured during the study. Discussions with
local ranchers indicated that normal accumulative snow depths would- be
slightly greater than any that were measured.
The precipitation features that are most influential to runoff-water
quality are that: (a) very little precipitation, and essentially no runoff,
occurs in the summer grazing period, (b) the rain and snow are almost al-
ways very low intensity, and (c) a significant amount of the precipitation
is snow which may form a significant snowpack depending on the precipita-
tion regime and location elevation. As discussed later, there is a signi-
ficant difference between water quality from rain on wet or frozen soil and
snowmelt water from beneath a snowpack. Thus the form, distribution, and
intensity all play significant roles in the amount of surface runoff and
its resultant quality.
Streamflow
Observed streamflow from the study watersheds 'followed the precipita-
tion trends very closely. The 1976-77 winter had far below expected runoff
amounts, while the two subsequent study years had more normal amounts. The
study period provided a wide variety of flow events in different sequences
which make the average results applicable to other situations.
Annual observed streamflow amounts are given in Table 4 for the check
and main watersheds. The flow is expressed in total volume (m^) plus
equivalent flow depths from the watershed area (mm). Peak flows are by
actual flow rate and are not corrected for contributing area.
The main watershed measuring weir intercepted seepage flow from the
saturated perched water tables and a small baseflow (seepage flow; ground-
water discharge) occurred during most spring months. An estimate was made
of the amount of the total flow that was generated as surface runoff by
22
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estimating the daily baseflow rate during days which had surface runoff.
These surface values are given in Table 4, and the monthly estimates are in
Appendix A. The check watershed had very little seepage flow, thus the
total flow is assumed to be surface runoff. For this study, the surface
runoff is the most important component because it is most likely to be
affected by the grazing operation.
Figures 5, 6, and 7 provide a daily summary of the precipitation,
runoff, snow depths, and snow cover during the winter season when nearly
all runoff occurred. These figures graphically show the features of the
three gaged seasons. The drought year, 1976-77, had few runoff days;
1977-78 had several periods of snow accumulation and melt; and 1978-79
developed a moderate snowpack which melted in a few days during early
February. These amounts and patterns are important to the water quality
interpretations because the melt rates, time of bare surface, and whether
there is snow present when runoff occurs will all likely impact the amount
of flushing action as the water flows over the pasture surface and thus
will influence the amount of sediment, manure, chemicals, and bacteria
transported in the streamflow.
A summary of total runoff during days when significant surface runoff
occurred is given in Table 5 for the complete study period. It is diffi-
cult to associate causative precipitation with each event because most
events include some melt of snow which occurred over various preceding
periods. Rain often is associated with the snowmelt period.
It is obvious from each of these event, daily, monthly, and annual
summaries that the check watershed had significantly less runoff than the
main watershed. The one exception was the frozen ground runoff events in
1976-77. This is not unexpected because the check watershed was situated
on an upland area with less steep topography and no wet bottomland. These
differences are always a problem in paired watershed studies, and espe-
cially so when the topography, geologic setting, and total areas differ
considerably. The surface runoff of the check area was only 40 and 30 per-
cent of the main watershed for the 1977-78 and 1978-79 seasons (Table 4
values). Little or no runoff was observed from its south side except in
frozen conditions. The effect of these differences on the water quality
interpretations is likely not so severe because the check area did have
sufficient runoff these two years to provide significant surface flushing
and numerous sampling opportunities to contrast simultaneously with those
from the main watershed.
Sediment
Daily measured sediment values are given in Appendix A and the annual
amounts in several different units in Table 6. These quantities were
developed by detailed integrations of numerous sediment sample concentra-
tions during each flow event with the corresponding flow rates. Runoff
hydrographs and sediment concentrations were graphed for each period of
surface flow. All anamolies were reviewed before numerical integrations
were made to determine event and daily discharges. Example graphs for the
check and main are shown in Figures 8 and 9, respectively.
23
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Sediment concentrations and total quantities were quite low for both
watersheds when compared with any other agriculturally used areas. The
average concentrations for all three years from the main watershed was 424
mi 11igrams/1 iter (mg/1) (Table 6), with the maximum sample having
12,700 mg/1 and minimum sample having one mg/1 (during baseflow). Average
sediment yield was 382 kg/ha. These values compare with mean concentra-
tions and yield of 7,400 mg/1 and 5,900 kg/ha, respectively, from wheat
land in our region (Missouri Flat Creek, 70 km^, 1961-1965), thus the
grassed pasture area is more than a full magnitude less than that delivered
from a much larger farmed watershed.
The check watershed had significantly less sediment discharge of only
19 kg/ha corresponding with the much less total streamflow, but the mean
concentrations were also only 10 to 20 percent of those from the main
watershed. The maximum sampled concentration was 2,105 mg/1. The much
lower concentrations and yields may partially be influenced by the topogra-
phic setting, but the observations indicate that much of this difference is
attributed to the presence of cattle on the main watershed. Many cattle
trails were developed throughout the main watershed and they were especi-
ally concentrated in the spring and channel area where watering occurred.
Several trails in this mid-watershed area intercepted the surface runoff
and became the controlling channels. They eroded significantly (5 to 10 cm
in depth) and this sediment went directly into the small streams.
The stream immediately above the main gaging location had small 15 to
30 cm banks that were largely unprotected by vegetation. Through watering
and grazing the cattle added some disturbance to this area which added to
the natural tendency for this small channel to erode. The upland channel
directly west of the weather station also had some exposed banks and a
small overfall which eroded some during the study. Again, there was some
cattle activity in this channel which undoubtedly aggravated the erosion.
Beyond the trails and channels there was little visible erosion. These
upland grass areas probably produced amounts similar to those measured on
the check watershed where there were no apparent areas exposed from good
grass vegetation.
Climatic Data
Basic climatic data were obtained throughout the study period to
document the existing conditions and aid in present and future interpreta-
tions. These data are supplied in Appendix B. Included are daily
maximum-minimum air temperature, daily pan evaporation during summer
months, and daily wind travel 30 cm above the soil surface at the edge of
the evaporation pan. Numerous other data such as soil temperatures, soil
frost depths, wind travel and direction at 3 m, and solar radiation were
obtained but are not included in this report.
Soil Moisture
Soil moisture was measured at the nine sites shown in Figure 1 on 28
dates during the study period. Frequency was about once each month with
24
-------
more readings during the growing season than in winter. Neutron probe
values were taken at 15 cm increments to 165 or 180 cm, plus gravimetric
samples taken 0 to 7, 7 to 15, 15 to 30, and 30 to 45 cm to define the
surface condition. All values were converted to percent by volume.
The depth distributions shown in Figure 10 for selected dates of a
mid-watershed site (No. 5) show the typical annual progression of soil
moisture. Spring is a recharge period by snowmelt and rain such that the
complete profile is at or above field capacity. With grass growth, in-
creased evaporative demand, reduced precipitation, and perhaps some deep
percolation, the soil moisture decreases rapidly throughout the summer
months. Wilting point is often approached by August in the upper layers.
These data also show that little water withdrawal occurs below 75 cm
(30 in.) by the predominantly shallow rooted grass.
Soil moisture relates to water quality through secondary processes. It
is a prime determinant of runoff volume and soil temperature, biologic
activity depending on soil moisture status, and grass growth and surface
residues controlled by soil moisture. These relationships must be kept in
mind when interpreting the hydrologic and water quality characteristics.
Groundwater
The level of water in two-inch diameter wells in and adjacent to the
stream alluvium were measured routinely during the study. These are shown
graphically in Figures 11, 12, and 13 for the three study years as depths
from the soil surface at the well site. Primarily, these groundwater levels
demonstrate the period of recharge by winter precipitation and drainout by
stream baseflow and evapotranspiration. No attempt has yet been made to
analyze gradients or more detailed porus media flow phenomena which
occurred. Without more detailed geologic investigation, this could probably
not be accomplished.
As with soil moisture, the groundwater has only an indirect effect on
discharged water quality. It does provide continuous seepage flow in the
lower 50 m of the main watershed channel which may have provided favorable
conditions for biologic activity not possible on the check watershed. More
directly, it did provide cattle water along the main channel which caused a
concentration of manure and trampling.
Water Temperature and Dissolved Oxygen
Temperature and dissolved oxygen (DO) are two basic water quality
parameters which may influence other water biologic activity. These were
measured manually during watershed inspections when streamflow was present
and are shown in Figures 14 and 15 for the check and main watersheds.
The annual variation of water temperature is apparent and the DO levels
were nearly always above 90 percent of saturation when flow was occurring.
The direct or indirect efforts on chemical and biologic water quality
parameters is not readily apparent. The range of these values does document
25
-------
that this is a cold stream during most of the discharge period with high
levels of DO. Combining these data with streamflow rates, BOD, and COD data
will further provide the general water quality status of this stream.
Manure Distribution
To provide direct measurements of the manure distribution on the main
watershed, counts were made three different dates during 1978 at early
summer, midsummer, and just after cattle were removed. The watershed was
stratified into three sampling zones of (a) high cattle use due to loafing
or watering, (b) along drainages, and (c) general grazing. Eight sample
sites were made in zone (a), 10 along the waterways, and 20 randomly placed
throughout the watershed. Each sample consisted of counting the number of
manure drops in a 50 m2 area and sampling the weight and size of the
droppings. The high use areas were difficult to count due to trampling of
the droppings.
Results of the fecal sampling are shown in Table 7. As can be seen, the
fecal deposits were not evenly distributed over the watershed, but were
concentrated in high-use areas and, to some extent, along drainages. The
high drainage density was probably due to the location of some animal trails
in the pasture. The situation is compounded when it is considered that two
of the high-use sites were in or immediately adjacent to drainage bottoms.
On an overall basis, the density of fecal deposits across the entire
watershed was 2,645 deposits/ha, providing a coverage of 1.45 percent.
Therefore, if the distribution of droppings were more uniform, the concen-
trations in the drainages would have approached that which was present
elsewhere in the nonconcentrated areas. In the opinion of the researchers,
one must suspect that the fecal bacteria counts in the runoff are a result
of the distribution of feces much more than the overall fecal density. This
is one subject which should be seriously considered for additional research.
WATER CHEMICALS AND OXYGEN
During the drouth water-year (1977), N and P losses in runoff from the
main and check watersheds were insignificant (Tables 8 and 9). While it may
appear that N and P losses are somewhat different for the main and check
watersheds, both watersheds were grazed the summer and fall of 1976, the
year of study initiation, so differences in losses can only be attributed to
hydrological differences between the two watersheds.
In water-year 1978, total N loss was only 3.8 and 0.48 kg/ha from the
main and check watersheds, respectively, which was more than during 1977 but
was still low (Tables 10 and 11). Nitrate concentrations were almost
negligible with a total loss of only 0.33 and .08 kg/ha NO3-N, respec-
tively. N parameters were higher from the main watershed than the check,
but no parameters were of sufficient magnitude to be of environmental
concern. N concentrations were high in runoff when the pond was drained and
26
-------
in the initial runoff samples in the fall after the summer grazing season.
These higher concentrations probably resulted from relatively fresh manure
particles being carried in the runoff from the pasture and within the main
stream channel. The pond was fenced to exclude cattle but they did have
access to the main channel below the pond to the sampling site. Throughout
this study, the periods of greatest nutrient concentrations were associated
with small runoff volumes such as early season events, summer events, or
pond drainage. Thus, these events contributed very little to the annual
constituent discharge. Average concentrations of N in the baseflow was
about one-half that of the surface runoff.
While NO3-N losses in runoff from the main watershed were slightly
greater in water-year 1979 than in 1978 (1.33 kg/ha vs. 0.33 kg/ha), most N
losses in runoff were less in 1979 (Tables 12 and 13), thus total N losses
were similar. Again, N losses in runoff were low and were generally lower
than would be expected in runoff from areas used for other agricultural
purposes. Total N losses were greater from the main watershed than the
check watershed. Exchangeable sediment NH^ was not run during
water-year 1979 because it was negligible during water-year 1978.
P deliveries from both watersheds were negligible during water-year 1977
(Tables 8 and 9). P deliveries in runoff were very low for water-year 1978
with runoff from the grazed area delivering only 0.2 kg/ha/yr ortho-P with a
total-P loss of only 1.27 kg/ha/yr (Tables 14 and 15). While these
deliveries are about 10 times more than from the check area, they are low.
The pond draining event on November 9 caused elevated P levels, probably due
to channel scour, but this was an artificially induced flow and not related
to natural streamflow. P levels in the runoff did increase when cattle were
present during the July 4 event; however, this was a very small event and
may not have reflected the true picture. Obviously the presence of cattle
will raise P levels in runoff, but this event would not be expected to be
representative. In any case, even with these high concentrations, the
annual discharge was negligible due to small streamflows during these
times. Very small amounts of P were delivered by baseflow even though
baseflow was about one-third, of the total water lost during the 1978 water
year.
In water-year 1979, P deliveries in runoff and baseflow were low from
the main and check watersheds (Tables 16 and 17). Generally, average
ortho-P concentrations in runoff from the main watershed were higher in
water-year 1979 than in 1978; in both years ortho-P in runoff decreased as
the length of time animals were off the pasture increased. Total-P lost in
runoff from the grazed watershed was slightly greater in water-year 1978
(1.27 kg/ha) than in water-year 1979 (0.93 kg/ha). If baseflow was added,
the values were 1.39 and 1.05 kg/ha, respectively. The greater total-P loss
in water-year 1978 was likely due to the December 10-15, 1977 event that had
a high average total-P concentration of 3.12 mg/1. Ortho-P and total-P
losses from the check watershed during water-year 1979 were 0.02 and
0.07 kg/ha, respectively.
27
-------
The oxygen demand, pH, SC, Cl~, and cation delivery for the main and
check watersheds for water-years 1977, 1978, and 1979 are summarized in
Tables D-l through D-6 in Appendix D. During the establishment year,
water-year 1977, oxygen demand for the main watershed was about twice that
of the check (probably due to stagnation); pH for the main watershed
appeared slightly more alkaline than the check, the SC of the main watershed
was somewhat greater than the check watershed, as was Cl~ and cation de-
livery. The oxygen demand of the runoff from the grazed watershed was about
three times that of the ungrazed watershed during water-year 1978 while
Cl~ and cations were about five times greater. Values for these
parameters increased in runoff from the main watershed when cattle were
present (July 4 event). Oxygen demand of runoff in water-year 1979 was
greater from the grazed area than in 1978, but runoff from the ungrazed area
was similar (Tables D-5 and D-6). Cations were not run during water-year
1979 because data from the previous year had shown that SC was well
correlated with the Na, K, Ca, and Mg present in the runoff.
Precipitation N, Groundwater Quality, and Profile Constituents
For water-year 1977, precipitation delivered 0.94 kg/ha NO3-N and
2.37 kg/ha NH|-N. Because of the drouth, insufficient sample volumes
were available to assess total-N delivery by precipitation. During
water-year 1978, precipitation delivered 2.19 kg/ha NO3-N, 1.86 kg/ha
NH$-N, and 4.31 kg/ha T-N. In water-year 1979, 1.1 kg/ha NO3-N,
1.96 kg/ha NH^-N, and 3.48 kg/ha T-N were received on the area in
precipitation. N delivered to the watershed area by precipitation was
greater than the quantities of N leaving the watershed with the runoff from
the grazed area for water-years 1977 and 1978, and only slightly less for
1979.
Groundwater quality under the grazed watershed was sampled periodically
during the three-year study. All samples obtained showed good water
quality, for example NO3-N content was always low and usually did not
exceed 1 ppm. Other parameters were of similar magnitude. N and ex-
changeable P in the soil profile did not show any concentrations that would
be considered environmentally unacceptable and during the study did not
increase in soil samples from the areas tested.
INDICATOR BACTERIA
TC counts in runoff showed little relationship to the presence or
absence of cattle as shown by the main and check watershed result summaries
presented in Tables 18, 19, 20, 21, 22, and 23. TC counts probably re-
sponded more to climate than to the cattle as shown by the check watershed
results (Tables 19, 21, and 23). The reader must recall that there was no
treatment difference between the main and check watershed for water-year
1977. From results of this study, TC counts appear to be useless for
determining stream pollution.
28
-------
In general, the FC and FS numbers decreased as expected throughout the
winter months. Their numbers, however, unexpectedly increased again in the
spring with warmer weather (see Tables 20-23). Also, the FC/FS ratios
varied more than expected, ranging from as high as 4/1 on the check water-
shed to 1/1 on the main watershed (see Tables 18-23).
FC/FS ratios of about 0.1 to 1.0 indicate cattle fecal contamination.
Runoff contaminated with cattle normally has a FC/FS ratio of about 0.7
while that with human had a FC/FS ratio of 4.0 and higher. Animal FC/FS
ratios will increase with time (Geldreich, 1976), but they should remain
less than one. The high FC/FS ratios long after cattle were removed from
the area would lead one to question the validity of the FC/FS ratio for
nonpoint areas. Doran and Linn (1979) have also questioned use of the FC/FS
ratio for this purpose. Furthermore, when animals were introduced back onto
the watershed, the June 4, 1977 readings showed high FC and FS numbers but a
FC/FS ratio of 0.02, which is indicative of wild animal fecal contamination
(Geldreich, 1976). During the three-year study period, except for a few
mice and squirrels, wildlife populations on the study areas were almost nil.
In 1977, average FC numbers exceeded recommended primary contact numbers
for six out of 11 events for the main watershed and met or exceeded'these
recommendations two out of four events on the check watershed (See Table
24). The apparent increase of numbers of FC and FS bacteria in runoff dur-
ing April and later in the prolonged absence of cattle and of appreciable
numbers of wildlife was surprising. Furthermore, the FC/FS ratios indicate
livestock were the fecal source. The same bacterial pattern occurred in
water-year 1978 on the main watershed (Table 20), while on the check water-
shed FS and possibly FC numbers increased in the spring (Table 21).
However, the FC/FS ratios on the check watershed for the April and May
events were not indicative of cattle fecal pollution. Geldreich (1976)
cites several examples which showed that FS can be indigenous to vegetation;
however, at least on the main watershed it appears that both FC and FS
multiplied in the spring correlating with a period of warm, dry weather
followed by wet weather. During water-year 1978, the cattle were just
removed when the October 30, 1977 event occurred with high numbers of FC and
FS in runoff from the main watershed with a FC/FS ratio indicative of cattle
fecal pollution. Surprisingly, the later November 8, 1977 event gave even
higher numbers of FC and FS in the runoff, but the FC/FS ratio was lower
than the October 30 event. These data are surprising because for a time
after manure deposition FC/FS ratios should increase because of rapid dieoff
of S_. bovis and _S. equinus; just the opposite situation existed here—both
FC and FS increased. No convenient explanations are evident. As the
water-year continued, FC and FS numbers decreased on both watersheds to
below maximum recommended primary contact numbers; but again coincident with
warm, wet weather in the spring, they increased in the runoff from both
watersheds. FC/FS ratios were indicative of wild animal pollution on the
check watershed during some events but not others. The data from the check
watershed for water-year 1978 indicate FC/FS ratios are not useful for
assessing nonpoint fecal pollution sources and data from the main watershed
indicate the same. FC are normally considered a good measure of recent
fecal pollution but from an average of 40 FC/100 ml of runoff for the
29
-------
March 12-15 event they increased to 5400 FC/100 ml of runoff in the
May 15-16 event in the absence of animals on the main watershed and from an
average of 10 FC/100 ml to 160 FC/100 ml for the same events on the check
watershed. These data cause the researchers to question the validity of
using FC, FS or FC/FS ratios for assessing recent cattle fecal pollution
from a nonpoint source such as grazing animals. During the July 4, 1978
event when animals were on the pasture, the FC and FS were much higher in
the runoff than at any time when animals were absent.
In water-year 1979, FC and FS numbers in runoff from the main watershed
and FC/FS ratios behaved similarly to those trends shown during water-year
1978 (Table 22). During water-year 1979, cattle were removed from the
watershed before any runoff event; however, the animals had been off the
watershed only four days before the November 14 event which obviously pro-
vided the high average numbers of FC and FS observed. FC and FS numbers
were again elevated during the May 4-9, 1979 event, long after cattle were
removed in October, 1978, but warm spring weather had occurred just before
the event.
By water-year 1979, FC for all events from the check watershed were low
and FC/FS ratios were very low (Table 23). However, almost three years were
required to establish this low level of FC on the check watershed. These
data indicate that present bacterial standards (Table 24) are inadequate for
assessing the bacterial pollution potential from nonpoint cattle grazed
areas.
The effect of grazing cattle on runoff water quality from the study
watersheds can be summarized by the following. TC in runoff, as others have
found, had an apparent relationship to cattle grazing operations, but
numbers were elevated when they should not have been. FC and FS numbers in
runoff from the grazed watershed were elevated when cattle were on the
pasture. After cattle were removed, FC and FS numbers generally declined
throughout the fall and winter months. However, after several months
absence of cattle from the area, FC and FS numbers in runoff from the grazed
watershed were elevated and in many cases exceeded suggested water quality
standards. FC and FS numbers appeared to increase in runoff from the grazed
area in the spring in rainfall runoff following a period of warm, dry
weather several months after animals were removed. FC/FS ratios in runoff
varied considerably and indicated recent cattle fecal pollution for long
periods of time after animals were off the grazed area. FS numbers in
runoff from the grazed and check areas did not change appreciably during the
study. The check was ungrazed from the fall of 1976 throughout the study.
FC numbers in runoff from the check were not consistently below the maximum
recommended numbers for primary contact until the 1979 water-year, although
FC numbers in the check watershed runoff during water-year 1978 were
generally below or close to the recommended primary contact standard. The
data would suggest using conventional FC/FS ratios or FC numbers in runoff
as a measurement of recent fecal pollution by cattle on a grazed area are of
limited value in the Pacific Northwest.
30
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PARAMETER RESPONSE AND SPATIAL DISTRIBUTION
Parameter Response
The type of runoff event affected the parameter response to streamflow
(Table 25). A typical parameter direct response to streamflow during rain-
fall runoff is shown for FC and FS in Figure 16. A typical inverse response
of the parameter SC to rainfall runoff is shown in Figure 17. With snowmelt
on thawed ground followed by rain, NO3-N does not follow the hydrograph
initially during snowmelt (Figure 18); however, when the ground thawed,
NO3 concentration increased. Ortho P did not follow the hydrograph at
any time during a snowfall-rain on frozen soil event (Figure 19). For the
same event, COD also did not appear to respond to streamflow until the
ground began to thaw on the second day of the event (Figure 20). Total P is
a good example of the pattern seen during a mixed snowmelt rainfall event
(Figure 21). The water quality parameter, in this case total-P, did not
respond to the streamflow increase caused by snowmelt, but did respond to
the later streamflow increase caused by rainfall runoff. During long and
large events, the check watershed behaved similarly. The highest check
watershed values often occurred in the first few runoff samples as the check
watershed channel was flushed since it had no base flow. For small, events,
parameter concentrations for check runoff therefore did not correlate well
with flow rates.
Spatial Distribution
Hand samples were collected from various locations within the watershed
during events in the 1978 and 1979 water-years to determine the effect of
grazing patterns, manure density and land cover on water quality parameter
concentrations. Of specific interest was whether the pollution load was
primarily a result of cattle activity in and immediately adjacent to the
stream channel (the "sacrifice area" between the north and south pastures)
or if the stream water quality reflected the grazing activity over the
entire watershed. The sampling site locations are shown in Figure 22.
During the 1978 water-year, samples were taken December 6, 1977 during a
small snowmelt/rainfal1 event; December 13, 1977, during the largest event
of the water-year; and on March 15, 1977, during a late winter medium sized
rainfall event. In water-year 1979 samples were taken from an event caused
primarily by snowmelt on February 13, 1979 during the largest event of the
water-year and of the entire study; February 27, 1979 during a large
rainfall/ snowmelt event; April 6, 1979, during an early spring rainfall
event and on May 4, 1979 at the beginning of a large spring rainfall event.
This last sampling occurred after indicator bacterial numbers had increased
above their late winter values.
Fecal density and distribution data were collected during the study by
the range management component of the project (see Section VI of the Range
Management Section). The amount of a drainage area within the pastured
watershed covered by feces varied from 20 percent for site 1 (sacrifice
pasture) to 0.7 percent for site 12 (northeast area) at the November 7, 1978
31
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sampTfng date (Table 26). The percent manure cover was determined three
times during the summer of 1978. The values obtained on Nov. 7, 1978 after
the cattle were removed from the watershed represent the fecal densities
present when these water quality samples were taken from the 1979 water year
runoff. FC and FS numbers in runoff from the various sampling sites within
the watershed did not correlate clearly with fecal deposition in water-year
1978 or 1979 (Table 27). In fact, no trends are apparent from the sites
sampled. Also, N and P in the runoff from the various sampling sites within
the pastured watershed did not appear to agree with manure deposition (Table
28).. Presumably vegetation and soil cover had a greater effect on runoff
nutrient content than did manure deposition.
These results would indicate that indicator bacteria and nutrients in
runoff from the main pasture areas were generally equal to those at the main
sampling station. The pollution load can be considered non-point source in
origin and not primarily a result of the greater grazing activity in the
sacrifice area.
32
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TABLE 3. MONTHLY PRECIPITATION DATA SUMMARY, ROCK CREEK WATERSHED,
1977, 1978, AND 1979 WATER YEARS
Site YR Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Total
(mi 1imeters)
Main
77
20.4*
8.7
67.8
17.2
19.7
68.2
48.8
250.8*
storage
78
33.8
79.9
127.3
64.0
66.0
43.0
75.0
53.2
18.6
21.1
52.7
28.5
663.1
79
2.2
56.6
76.0
41.0
125.0
48.0
71.5
50.3
23.4
12.0*
—
—
506.0*
Main "1"
77
70.1
17.0
18.5
65.5
44.7
tipping
78
40.9*
18.3
25.1
51.8
27.2
79
17.8*
20.3
8.9*
—
—
—
Check
77
12.2*
33.8
20.1
18.3
50.1
8.7
74.4
18.7
21.4
70.6
51.4
380.0*
storage
78
37.3
81.1
137.6
63.0
69.0
45.0
81.0
54.0
20.0
28.0
53.0
31.0
700.0
79
1.0
58.0
74.0
43.0
135.0
48.0
74.0
49.0
25.0
13.0*
—
—
520.0*
Check +
77
71.6
17.0
18.0
66.0
47.2
tipping
78
51.1
19.3
24.9
49.3
26.2
—
79
18.0*
8.6*
—
—
—
Weighing
77
20.0*
21.0
19.5
57.0
9.5
67.0
17.5
17.5
64.0
47.0
340.0*
78
31.0
78.5
143.5
66.5
67.0
40.0
73.0
50.0
18.0
26.0
53.0
29.5
676.0
79
2.0
66.5
79.0
56.0
123.0
50.5
65.5
46.5
24.0
10.0*
—
—
523.0*
Watershed t
77
12.2*
33.8
20.6
18.9
53.6
9.0
70.2
17.5
19.0
66.9
47.8
369.5*
78
34.0
79.8
136.1
64.5
67.3
42.7
76.3
52.1
18.8
25.0
52.0
27.9
676.5
79
1.8
60.4
76.3
46.7
127.6
48.8
70.3
48.6
24.1
11.7*
516.3*
(continued)
-------
TABLE 3 (continued)
Site
YR
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Total
Moscow
77
58.7
23.6
30.7
19.6
19.3
42.4
11.9
72.6
15.0
17.0
72.6
63.8
447.2
78
27.7
99.1
119.6
77.2
58.4
41.4
120.4
56.9
23.6
26.7
53.6
39.4
744.0
79
2.3
48.8
64.0
27.2
104.6
52.3
83.8
71.6
25.7
12.4
25.1
10.4
528.2
Normal
49.5
73.2
76.7
74.2
52.3
46.5
46.2
46.2
45.5
14.5
17.8
32.0
574.6
Potlatch
77
37.1
17.0
39.6
27.2
29.7
45.7
9.9
69.6
19.6
19.3
45.0
49.3
409.0
78
36.3
84.6
153.7
77.5
56.4
35.3
107.2
49.5
23.9
42.2
55.6
36.6
758.8
79
1.5
63.8
67.6
47.2
124.2
62.2
59.7
50.0
25.4
17.3 '
50.8
12.2
581.9
Normal
53.8
73.2
82.3
79.2
58.2
51.3
47.8
50.0
55.6
17.3
18.3
35.1
622.1
* Value represents only part of month or year,
t
Data from tipping bucket gage^ omitted during periods of heating because gages evaporated the pre-
cipitation and significantly under-recorded.
t The watershed value is an average between the storage and weighing gage values (where full month
data available) during October through April and the average of all the gages during May through
September,
-------
TABLE 4. ANNUAL STREAMFLOW SUMMARY
1977*
1978
1979t
Main
Check
Main
Check
Main
Check
Precipitation, mm
370
676
516
Runoff
Volume, m3
2,451
308
38,193
422
40,623
370
Depth, rnm
Total Flow
11
34
178
46
189
41
Surface Flow
10
34
119
46
136
41
Peak flow, 1/sec
26
4
103
4
145
3
* Measurements Nov. 4, 1976 to Sep. 30, 1977
^ Measurements Oct. 1, 1978 to July 5, 1979
-------
TABLE 5. RUNOFF EVENT SUMMARY
Mair
) watershed
Check
watershed
Peak
Volume
Peak
Volume
Event dates
1 / sec
mm*
1/sec
mm*
Event type
1977
Dec. 26-27,
1976
3.6
161.0
0.7
1.5
82.9
9.1
Snowmelt/rain on frozen ground
Jan. 16-19,
1977
26.4
1,775.0
8.3
3.9
203.7
22.5
Snowmelt/rain on frozen ground
Feb. 8-10
1.6
94.5
0.4
0.4
0.0
1.3
Rain/snowmelt
Feb. 28-Mar
. 1
0.6
25.4
0.1
0.0
0.0
0.0
Rain on :
;now
Mar. 7-10
1.2
65.4
0.3
-
-
-
Rain and
snow
Mar 7-9
0.2
2.8
0.3
Rain and
snow
Mar. 15-20
0.5
51.9
0.2
-
-
-
Snowmelt
and rain
Mar. 19
-
-
-
0.0
0.0
0.0
Snowmelt
and rain
Mar. 27-28
0.6
15.8
0.1
-
-
—
Snow and
rain
Mar. 27
-
-
-
0.0
0.0
0.0
Snow and
rain
Apr. 13-14
0.5
4.9
0.0
0.0
0.0
0.0
Rain
May 2-4
0.1
3.6
0.0
0.0
0.0
0.0
Rain
May 17-18
0.2
11.8
0.0
0.0
0.0
0.0
Rain
May 26-27
0.4
3.7
0.0
0.0
0.0
0.0
Rain
June 4
0.0
0.2
0.0
0.0
0.0
0.0
Rain
Nov. 8
38.6
23.0
0.1
—
Draining
water pond
Nov. 25-29
13.4
302.0
1.4
0.7
15.0
1.6
Snowmelt
and rain
Dec. 1-3
4.4
162.0
0.8
0.6
15.3
1.7
Snowmelt
and rain
Dec. 6-7
4.0
107.0
0.5
0.2
4.0
0.4
Snowmelt
and rain
Dec. 10-11
46.4
1,223.0
5.7
1.6
35.9
4.0
Snowmelt
and rain
Dec. 13
102.9
2,589.0
12.0
3.2
56.7
6.3
Rain
Dec. 14
82.8
1,541.0
7.2
3.5
27.7
3.1
Rain
Dec. 15
42.1
1,077.0
5.0
2.0
18.8
2.1
Rain
(continued)
-------
TABLE 5 (continued)
Main watershed Check watershed
Peak Volume Peak Volume
Event dates 1/sec irP mm- 1/sec iP mm Event type
1978
Jan. 5-6
30.8
2,916.0
13.6
0.6
53.1
5.9
Snowmelt and rain
Jan. 8-9
32.3
2,420.0
11.3
0.7
33.8
3.7
Rain and snowmelt
Jan. 15-16
12.8
827.0
3.8
0.2
4.8
0.5
Rain and limited snowmelt
Feb. 2-4
42.7
2,762.0
12.8
1.2
40.7
4.5
. Snowmelt and some rain
Feb. 5-6
46.4
2,493.0
11.6
1.1
19.6
2.1
Rain
Feb. 7
60.0
1,602.0
7.5
1.7
21.2
2.3
Rain
Feb. 24 - Mar. 5
7.2
2,240.0
10.4
0.1
9.4
1.0
Snowmelt and rain
Mar. 7-9
13.4
1,238.0
5.8
0.3
9.6
1.0
Rain
Mar. 12-15
10.7
1,152.0
5.4
0.2
5.6
0.6
Snowmelt
Apr. 1-2
9.1
642.0
3.0
0.6
14.2
1.6
Rain
Apr. 4-5
4.8
283.0
1.3
0.1
2.1
0.2
Rain
Apr. 7
12.5
391.0
1.8
0.5
7.3
0.8
Snow and rain
Apr. 16
4.1
123.0
0.6
0.2
2.5
0.3
Rain and snow
Apr. 27-28
1.2
166.0
0.8
0.1
4.2
0.5
Rain
May 15-17
9.1
149.0
0.7
1.1
5.8
0.6
Rain
May 21
1.1
11.0
0.1
-
-
-
Rain (intense)
Nov. 4
0.1
0.9
0.0
_
Rain
Nov. 17
0.3
6.0
0.0
-
-
_
Rain
Dec. 3-4
1.0
47.3
0.2
0.3
10.1
1.1
Snowmelt
Dec. 11
2.7
96.7
0.4
0.6
18.9
2.1
Rain on snow
Dec. 23-24
1.1
68.3
0.3
0.3
11.0
1.2
Snowmelt
(continued
-------
TABLE 5 (continued)
Main watershed Check watershed
Peak Volume peak 'Volume
Event dates 1/sec 11P rniiT 1 /sec nr mm Event type
1979
Feb. 6-7
1.1
50.4
0.2
0.1
3.0
0.3
Rain on snow
Feb. 9-14
145.1
12,523.3
58.2
1.9
169.4
18.7
Rain on snow
Feb. 17-20
9.1
1,487.1
6.9
0.2
12.1
1.3
Snowmelt and rain
Feb. 24-28
37.0
5,142.7
23.9
0.8
42.3
4.7
Rain on snow
Mar. 4-7
2 3.2
4,459.0
20.7
0.2
15.8
1.7
Rain
Mar. 15-16
8.2
650.7
3.0
0.1
1.7
0.2
Rain
Mar. 27-28
11.2
532.2
2.5
0.4
6.4
0.7
Rain
Apr. 2-4
13.4
1,001.4
4.7
0.3
4.7
0.5
Snowmelt
Apr. 6
28.4
834.9
3.9
0.9
11.8
1.3
Rain
Apr. 8-9
16.5
875.9
4.1
0.3
3.1
0.3
Rain
Apr. 13-14
40.4
675.5
3.1
1.1
4.1
0.5
Rain
Apr. 16-17
21.6
631.8
2.9
0.4
3.9
0.4
Rain
Apr. 23-24
14.0
623.4
2.9
0.5
6.7
0.7
Rain
May 4-6
51.6
3,079.6
14.3
3.0
43.8
4.8
Rain
May 8-9
7.6
459.4
2.1
-
-
-
Rain
* Expressed as depth from contributing area.
-------
TABLE 6. ANNUAL SEDIMENT SUMMARY
1977*
1978
1979+
3-yr avg
Main Check
Main
Check
Main Check
Main Check
Precipitation, mm
370
676
516
517
Surface Runoff, mm
10 34
119
46
136
41
88 40
Sediment
Yield, kg
877 15
10,489
25
13,291
12
8,219 17
Yield, kg/ha
41 16
488
28
618
13
382 19
Avg. conc., mg/1
408 49
410
60
455
32
424 47
* Measurements Nov
. 4, 1976 to
Sep. 30
, 1977.
+ Measurements Oct
. 1, 1978 to July 5,
1979.
39
-------
TABLE 7. ESTIMATED DENSITY AND COVERAGE OF CATTLE FECAL DEPOSITS ON THE
ROCK CREEK WATERSHED AT THREE TIMES DURING 1978.*
Spatial
Date Location Density Coverage
(deposita/ha)
(Percent)
June 27
High use
4,900 (3,600 - 6,200)
2.5
Drai nage
1,760 (1,140 - 2,830)
0.9
Watershed
1,000 ( 780. - 1,220)
0.5
August 20
High use
9,124 (7,800 - 10,380)
4.6
Drainage
3,900 (2,860 - 4,940)
2.0
Watershed
1,910 (1,600 - 2,200)
1.0
November 4
High use
12,400 (10,164 - 14,636)
6.2
Drai nage
4,700 (3,640 - 5,760)
2.4
Watershed
2,560 (2,200 - 2,920)
1.4
* The estimates are stratified into high use sites, drainages, and the
remaining part of the watershed.
This estimate may be affected by nonsampling error. See text.
40
-------
TABLE 8. NITROGEN AND P DISCHARGE FROM THE ROCK CREEK MAIN
WATERSHED, 1977 WATER YEAR
Event
dates
Water
delivery NO3-N
Soluble
nh4+
TKN
Ortho
P
Total
P
(m3) (Average mg/1)
1976
Dec 26-27,
158.3
0.17
0.13
-
1.0
-
1977
Jan 16-19,
1,795.8
0.05
0.04
1.1
0.97
1.6
Feb 8-11
105.0
0.13
0.11
1.2
0.54
0.75
Feb 28-Mar 1
24.9
0.18
0.29
0.9
0.14
0.3
Mar 7-10
65.5
0.07
0.05
0.8
0.13
0.85
Mar 15-20
42.1
0.02
0.02
0.6
0.10
0.6
Mar 27-28
15.75
0.002
0.02
0.3
0.09
0.8
Apr 13-14
4.9
0.01
0.01
-
0.16
-
May 2-4
3.6
0.14
0.07
2.2
0.25
0.85
May 17-18
11.8
0.004
0.008
0.8
0.20
0.5
May 26-27
3.7
0.003
0.005
1.0
0.17
0.5
Jun 4
0.2
0.02
0.35
1.3
0.05
0.5
g/ha
Total delivery
for water year 2,232 6.5 5.3 92
-------
TABLE 9. NITROGEN AND P DISHCAR6E FROM THE ROCK CREEK CHECK
WATERSHED, 1977 WATER YEAR
Event
dates
Water
delivery
NO3-N
Soluble
NH| tkn
Ortho
P
Total
P
(m3)
-(Average nig/1)-
1976
Dec 26-27
82.9
0.05
0.10
—
0.32
1977
Jan 16-19,
Feb 8-10
206.9
12.2
0.04
0.10
0.01
0.16
' 0.7
1.2
0.54
0.33
0.7
0.5
Mar 8-9
Mar 19
Mar 27
2.6
<1.0
<1.0
0.15
0.015
0.05
0.01
0.02
0.0
0.6
0.10
0.16
0.15
-
g/ha
Total delivery
for water year 305 15.6 13.7 158
-------
TABLE 10. NITROGEN DISCHARGE FROM THE ROCK CREEK MAIN WATERSHED, 1978 WATER YEAR
Water
DIS
DIS
DIS
DIS
DIS
Event dates
delivery
N03-N
NH4-N
ORG-N
TKN
T-N
T-N
Event type
(m3)
-(Average mg/1)
1977
Oct. 30-Nov.
2
15.6
0.74
0.28
1.15
1.44
2.11
3.42
Rain
Nov. 8
22.9
0.04
0.29
1.15
1.44
1.55
30.70
Pond draining
Nov. 13-16
26.0
0.07
0.13
0.58
0.73
0.78
1.38
Rain
Nov. 25-30
304.5
0.03
0.03
0.30
0.31
0.32
0.91
Snowmelt/rain
Dec. 1-4
172.3
0.21
. 0.18
0.95
1.07
1.31
1.80
Snowmelt/rain
Dec. 6-7
107.2
0.37
0.17
1.16
1.31
1.62
1.85
Snowmelt/rain
Dec. 10-15
6,717.9
0.36
0.02
1.10
1.12
1.46
8.10
Rain
1978
Jan 5-9
5,874.6
0.40
0.01
0.66
0.67
1.08
1.65
Snowmelt/1imited rain
Feb. 3-7
6,699.8
0.20
0.03
0.68
0.71
0.89
1.55
Snowmelt/rain
Feb. 26-Mar.
2
1,417.5
0.06
0.01
0.33
0.34
0.40
0.59
Snowmelt/rain
Mar 8-9
1,067.6
0.10
0.03
0.34
0.38
0.48
0.79
Rain
Mar. 12-15
1,152.4
0.09
0.01
0.53
0.54
0.64
0.74
Snowmelt
Apr. 1-7
1,518.6
0.13
0.01
0.90
0.91
1.06
1.19
Rain/sleet/snow
Apr. 16
122.7
0.12
0.04
0.92
0.97
1.09
1.25
Snow/hai1/rain
Apr. 27-28
166.4
0.17
0.02
0.88
0.89
1.09
1.74
Rain
May 15-16
113.0
3.86
0.90
0.73
1.62
5.52
6.06
Rain
July 4
6.3
2.27
0.24
0.37
0.66
2.93
8.08
Rain
kg/ha-
Total delivery 25,505.0
0.33
0.04
0.90
0.94
1.25
3.80
Baseflow
12,098.0
0.09
0.01
0.29
0.30
0.39
0.57
(continued)
-------
TABLE 10. (continued)
T-N
EXCH-NH4
Event dates
ORG-N
TKN
T-N
SED
SED
Event type
-(Average nig/1)
1977
Oct. 30-Nov. 2
2.32
2.62
3.42
1.41
0.24
Rain
Nov. 8
30.40
30.60
30.70
29.10
0.00
Pond draining
Nov. 13-16
1.18
1.29
1.38
0.60
0.00
Rain
Nov. 25-30
0.88
0.89
0.91
0.59
0.01
Snowmelt/rain
Dec. 1-4
1.33
1.58
1.80
0.49
0.10
Snowmelt/rain
Dec. 6-7
1.26
1.44
1.85
0.23
0.11
Snowmelt/rain
Dec. 10-15
7.72
7.74
8.10
6.64
0.02
Rain
1978
Jan 5-9
1.21
1.24
1.65
0.57
0.02
Snowmelt/1imited rain
Feb. 3-7
1.31
1.66
1.55
0.66
0.03
Snowmelt/rain
Feb. 26-Mar. 2
0.52
0.53
0.59
0.19
0.00
Snowmelt/rain
Mar 8-9
0.66
0.70
0.79
•0.31
0.00
Rain
Mar. 12-15
0.64
0.65
0.74
0.10
0.00
Snowmelt
Apr. 1-7
1.04
1.06
1.19
0.13
0.00
Rain/sleet/snow
Apr. 16
1.09
1.14
1.25
0.16
0.00
Snow/hai i/rain
Apr. 27-28
1.56
1.57
1.74
0.65
0.00
Rain
May 15-16
1.29
2.20
6.06
0.54
0.00
Rain
July 4
5.43
5.81
8.08
5.15
0.09
Rain
(kg/ha)—
Total delivery
3.42
3.56
3.80
2.54
0.02
Baseflow
0.47
0.48
0.57
0.18
0.005
-------
TABLE 11. NITROGEN DISCHARGE FROM THE ROCK CREEK CHECK
WATERSHED, 1978 WATER YEAR
Water
DIS
DIS
DIS
DIS
DIS
Event dates
delivery
NO3-N
NH4-N
ORG-N
TKN
T-N
Event type
(m3)
(Average mg/1 )-
1977
Nov 25-27
14.9
0.01
0.04
0.38
0.39
0.41
Snowmelt/rain
Dec 1-3
15.3
0.02
0.12
0.52
0.61
0.64
Snowmelt/rain
Dec 6-7
4.0
0.03
0.10
1.03
1.10
1.13
Snowmelt/rain
Dec 10-16
143.0
0.15
0.02
0.57
0.58
0.72
Rain
1978
Jan 5-9
89.3
0.18
0.03
0.47
0.50
0.67
Snowmelt/1imited rain
Feb 2-7
81.6
0.03
0.03
0.47
0.50
0.54
Snowmelt/rain
Feb 26-Mar 1
7.2
0.06
0.03
0.44
0.47
0.54
Snowmelt/rain
Mar 8-9
9.6
0.10
0.03
0.34
0.36
0.44
Rain
Mar 12-15
5.5
0.06
0.00
0.31
0.31
0.37
Snowmelt
Apr 1-7
23.6
0.21
0.01
1.10
1.11
1.32
Rain/sleet/snow
Apr 16
2.5
0.20
0.08
1.08
1.20
1.40
Snow/hai1/rain
Apr 27-28
4.2
0.31
0.02
1.57
1.60
1.90
Rain
May 15-16
5.8
5.03
0.09
1.91
2.00
7.10
Rain
(kg/ha)
Total delivery 407.0 0.08 0.01 0.26 0.28 0.36
(continued)
-------
TABLE 11. (continued)
Event dates
ORG-N
TKN
T-N
SED-N
EXCH-NH4
SED
Event type
-(Average nig/1)
1977
Nov 25-27
0.76
0.80
0.81
0.40
0.02
Snowmelt/rain
Dec 1-3
1.08
1 .ID
1.21
0.57
0.01
Snowmelt/rain
Dec 6-7
1.17
1.24
1.28
0.15
0.01
Snowmelt/rain
Dec 10-16
0.75
0.78
0.93
0.21
0.03
Rain
1978
Jan 5-9
0.83
0.85
1.03
0.36
0.00
Snowmelt/1imited rain
Feb 2-7
0.66
0.70
0.73
0.19
0.00
Snowmelt/rain
Feb 26-Mar 1
0.58
0.65
0.72
0.18
0.04
Snowmelt/rain
Mar 8-9
0.70
0.73
0.81
0.37
0.01
Rain
Mar 12-15
0.58
0.64
0.71
0.34
0.07
Snowmelt
Apr 1-7
1.28
1.31
1.51
0.19
0.01
Rain/sleet/snow
Apr 16
1.52
1.60
1.80
0.40
0.00
Snow/hai1/rain
Apr 27-28
1.95
1.98
2.26
0.36
0.00
Rain
May 15-16
2.14
2.24
7.30
0.20
0.00
Rain
(kg/ha)
Total delivery 0.38 0.39 0.48 0.12 0.004
-------
TABLE 12. NITROGEN DISCHARGE FROM THE ROCK CREEK MAIN
WATERSHED, 1979 WATER YEAR
Water
DIS
DIS
DIS
DIS
DIS
Event dates
delivery
NO3-N
NH4-N
ORG-N
TKN
T-N
ORG-N
TKN
T-N
SED-i
(m3)
(Average mg/1)
1978
Nov 4
0.9
1.778
.667
2.111
2.78
4.56
3.00
3.67
5.44
.89
Nov 17
6.0
.950
.400
2.517
2.92
3.87
2.92
3.32
4.25
.38
Nov 30-Dec 4
65.6
.688
.072
.712
.78
1.47
.98
1.05
1.74
.27
Dec 11
96.7
.203
.114
.504
.62
.82
.58
6.91
.89
.07
Dec 23-24
68.4
.522
.010
.822
.83
1.35
1.08
1.09
1.62
.26
1979
Feb 6-7
51.4
.837
.247
1.113
1.36
2.19
1.49
1.73
2.57
.37
Feb 9-14
12,523.2
1.731
.134
.944
1.08
2.81
2.11
2.24
3.97
1.16
Feb 18-20
1,254.6
.909
.082
.830
.91
1.82
.95
1.03
1.94
1.11
Feb 25-28
5,012.5
.668
.056
.580
.64
1.30
.84
.90
1.57
.26
Mar 4-8
4,968.2
.360
.050
.623
.67
1.03
.78
.83
1.19
.16
Mar 15-18
1,066.5
.141
.025
.861
.89
1.03
1.21
1.23
1.37
.33
Mar 27-28
532.2
.163
.079
.804
.88
1.05
1.18
1.26
1.45
.37
Apr 2-4
1,001.4
.067
.034
.747
.78
.85
1.05
1.08
1.15
.31
Apr 6-10
2,510.2
.109
.047
.739
.79
.89
1.06
1.11
1.21
.32
Apr 12-13
675.4
.091
.030
.729
.76
.85
1.42
1.45
1.54
.70
Apr 16-17
631.8
.101
.046
.906
.95
1.05
1.24
1.29
1.39
.34
Apr 23-24
623.5
.060
.039
.904
.94
1.00
1.21
1.25
1.31
.30
May 4-9
3,926.8
.224
.045
.748
.79
1.02
1.09
1.19
1.36
.35
(kg/ha)
Total delivery 35,015 1.33 .01 1.28 1.42 2.75 2.25 2.43 3.76 .96
Baseflow 5,618 .15 .01 .19 .20 .35 .24 .20 .35 .05
-------
TABLE 13. NITROGEN DISCHARGE FROM THE ROCK CREEK CHECK
WATERSHED, 1579 WATER YEAR
Event dates
Water
del ivery
DIS
NO3-N
DIS
NH4-N
DIS
ORG-N
DIS
TKN
DIS
T-N
(niJ)
[ Av/pranp mn 11
1978
Dec 3-4
10.2
.059
.0
.304
.304
0.37
Dec 11
18.9
.0
.0
.429
.429
0.43
Dec 23-24
11.1
.009
.0
.486
.486
0.49
1979
Feb 6-7
2.9
.517
.103
1.000
1.100
1.66
Feb 9-15
170.1
.155
.036
.460
.50
0.65
Feb 17-20
12.1
.190
.025
.793
.82
1.01
Feb 25-28
42.4
.257
.024
.514
.54
0.79
Mar 4-7
15.8
.177
.025
.563
.57
0.78
Mar 16
1.7
.294
.059
.824
.88
1.12
Mar 27-28
6.4
.328
.062
1.172
1.23
1.56
Apr 2-4
4.7
.064
.064
.809
.87
0.92
Apr 6-9
15.1
.219
.066
1.020
1.09
1.31
Apr 12-13
4.2
.119
.048
.738
.79
.88
Apr 16-17
3.9
.179
.103
1.103
1.21
1.38
Apr 24
6.7
.090
.045
1.164
1.21
1.30
May 4-6
43.9
.248
.039
.911
.95
1.20
(kg/ha)
Total delivery 370 .07 .01 0.25 0.26 0.33
(continued)
-------
TABLE 13. (continued)
Event dates ORG-N TKN T-N SED-N
(Average mg/1)
1978
Dec 3-4
0.36
0.36
0.43
0.06
Dec 11
0.54
0.54
0.54
0.11
Dec 23-24
0.53
0.53
0.54
0.05
1979
Feb 6-7
2.03
2.17
2.69
1.03
Feb 9-15
0.79
0.82
0.98
0.33
Feb 17-20
1.24
1.27
1.46
0.45
Feb 25-28
0.79
0.82
1.07
0.28
Mar 4-7
0.89
0.92
1.11
0.33
Mar 16
1.47
1.53
1.77
0.65
Mar 27-28
1.77
1.83
2.17
0.61
Apr 2-4
1.02
1.09
1.17
0.25
Apr 6-9
1.36
1.43
1.65
0.34
Apr 12-13
1.47
1.52
1.62
0.74
Apr 16-17
1.46
1.56
1.74
0.36
Apr 24
1.37
1.42
1.51
0.21
May 4-6
1.21
1.25
1.50
0.30
(kg/ha)
Total delivery 0.37 0.39 0.46 0.13
-------
TABLE 14. PHOSPHORUS DISCHARGE FROM THE ROCK CREEK MAIN
WATERSHED, 1978 WATER YEAR
Event dates
Water
delivery
DIS
Ortho-P
T-DIS
-P T-P
T-Sed-P
Event type
(m3)
— (Average ing/1)
1977
Oct 30-Nov 2
15.6
.29
.47
.88
.41
Rain
Nov 8
22.9
.13
.35
10.80
10.40
Pond draining
Nov 13-16
26.0
.17
.21
.30
.09
Rain
Nov 25-30
304.5
.28
.33
.48
.15
Snowmelt/rain
Dec 1-4
172.3
.21
.23
.53
.31
Snowmelt/rain
Dec 6-7
107.2
.18
.26
.39
.13
Snowmelt/rain
Dec 10-15
6,717.9
.25
.40
3.12
2.72
Rain
1978
Jan 5-9
5,874.6
.16
.20
.25
.05
Snowmelt/1imited rail
Feb 3-7
6,699.8
.16
.20
.42
.22
Snowmelt/rain
Feb 26-Mar 2
1,417.5
.09
.19
.24
.05
Snowmelt/rain
Mar 8-9
1,067.6
.07
.13
.29
.16
Rain
Mar 12-15
1,152.4
.07
.15
.24
.09
Snowmelt
Apr 1-7
1,518.6
.08
.17
.35
.18
Rain/sleet/snow
Apr 16
122.7
.08
.16
.29
.12
Snow/hai1/rain
Apr 27-28
166.4
.09
.14
.32
.18
Rain
May 15-6
113.0
.29
.53
.78
.24
Rain
July 4
6.3
.84
1.25
1.79
.54
Rain
Total delivery
Baseflow delivery
25,505
12,098
o o
• • |
O rv> 1
1
1
1
1
1 !
I !
0.3
0.09
(kg/ha)
1.27
0.12
0.98
0.03
-------
TABLE 15. PHOSPHORUS DISCHARGES FROM THE ROCK CREEK CHECK
WATERSHED, 1978 WATER YEAR
Event dates
Water
delivery
DIS
Ortho-P
T-DIS-P T
-P
T-Sed-P
Event type
(m3)
— (Average mg/1)
1977
Nov 25-27
14.9
.07
.11
.40
.29
Snowmelt/rain
Dec 1-3
15.3
.07
.09
.25
.16
Snowmelt/rain
Dec 6-7
4.0
.03
.05
.23
.18
Snowmelt/rain
Dec 10-16
143.0
.03
.11
.25
.14
Rain
1978
Jan 5-9
89.3
.03
.12
.15
.03
Snowmelt/1imited rain
Feb 2-7
81.6
.04
.12
.24
.12
Snowmelt/rain
Feb 26-Mar 1
7.2
.01
.03
.10
.07
Snowmelt/rain
Mar 8-9
9.6
.02
.06
.20
.14
Rain
Mar 12-15
5.5
.01
.05
.16
.11
Snowmelt
Apr 1-7
23.6
.03
.12
.26
.14
Rain/sleet/snow
Apr 16
2.5
.04
.14
.28
.14
Snow/hai1/rain
Apr 27-28
4.2
.05
.15
.29
.14
Rain
May 15-16
5.8
.03
.10
.25
.15
Rain
(kg/ha)
Total delivery 407.0 0.01 0.05 0.1 0.05
-------
TABLE 16. PHOSPHORUS DISCHARGES FROM THE ROCK CREEK MAIN
WATERSHED, 1S79 WATER YEAR
Event dates
Water
delivery
DIS
Ortho-P
T-DIS-P
T-P
T-Sed-P
(M3)
—(Average mg/1)
1978
Nov 4
0.9
1.00
1.44
1.67
.22
Nov 17
6.0
.73
1.09
1.23
.13
Nov 30-Dec 4
65.6
.51
.56
.63
.07
Dec 11
96.7
.43
.55
.74
.20
Dec 23-24
68.4
.20
.32
.37
.05
1978
Feb 6-7
51.4
.23
.28
.43
.17
Feb 9-14
12,523.2
.32
.47
.94
.47
Feb 18-20
1,254.6
.25
.31
.38
.07
Feb 25-28
5,012.5
.18
.23
.34
.11
Mar 4-8
4,968.2
.24
.29
.44
.15
Mar 15-18
1,066.5
.20
.23
.37
.14
Mar 27-28
532.2
.18
.24
.37
.13
Apr' 2-4
1,001.4
.12
.16
.20
.04
Apr 6-10
2,510.2
.14
.30
.43
.13
Apr 12-13
675.4
.15
.24
.41
.16
Apr 16-17
631.8
. 18
.23
.27
.04
Apr 23-24
623.5
.13
.22
.31
.08
May 4-9
3,926.8
.08
.22
.34
.13
Total delivery
Baseflow delivery
35,015
5,618
0.36
0.05
0.54
0.08
-(kg/ha)
0.93
0.12
0.39
0.04
-------
TABLE 17. PHOSPHORUS DISCHARGES FROM THE ROCK CREEK CHECK
WATERSHED, 1979 WATER YEAR
Event dates
Water
delivery
DIS
Ortho-P
T-DIS-P
T-P
T-Sed-P
(M3)
— (Average mg/1)
1978
Dec 3-4
10.2
0.03
.05
.08
.03
Dec 11
18.9
0.04
.07
.13
.06
Dec 23-24
11.1
0.01
.02
.03
.01
Feb 6-7
2.9
0.10
.17
.45
.28
Feb 9-15
170.1
0.04
.06
.13
.07
Feb 17-20
12.1
0.05
.05
.17
.12
Feb 25-28
42.4
0.04
.05
.14
.09
1979
Mar 4-7
15.8
0.07
.08
.18
.10
Mar 16
1.7
0.12
.18
.41
.24
Mar 27-28
6.4
0.19
.20
.41
.21
Apr 2-4
4.7
0.09
.09
.18
.09
Apr 6-9
15.1
0.05
.23
.49
.26
Apr 12-13
4.2
0.02
.07
.24
.17
Apr 16-17
3.9
0.10
.13
.28
.15
Apr 24
6.7
0.06
.14
.30
.16
May 4-6
43.9
0.04
.14
.26
.12
(kg/ha)
Total delivery 370.0 0.02 0.04 0.07 0.04
-------
TABLE 18. AVERAGE CONCENTRATIONS OF FC, FS, AND TC IN RUNOFF FROM THE ROCK CREEK MAIN
WATERSHED, 1977 WATER YEAR
Event dates
Water
delivery
Total C
Fecal C
Fecal S
FC/FS
Event type
(M3)
^ / \ V V- 1 U VjV> M \J % f X U V till J
1976
Dec. 26-27
158.3
Snowmelt/rain
1977
Jan 16-19
1,795.8
13,850
395
6,780
0.06
Snowmelt/rain
Feb. 8-11
105.0
200,000
3,300
3,300
1.00
Snowmelt/rain
Feb. 28-Mar 1
24.9
34,000
72
250
0.30
Snowmelt/rain
Mar. 7-10
65.5
24,000
69
91
0.76
Rain/snow/rain
Mar. 15-20
52.1
5,600
31
31
1.00
Snowmelt/rain
Mar. 27-28
15.75
5,300
11
52
0.20
Snowmelt/rain
Apr. 13-14
4.9
3.7xl06
710
8,250
0.09
Rain
May 2-4
3.6
3.2xl06
3,660
8,450
0.40
Rain
May 17-18
11.8
276,000
177
1,650
0.10
Rain
May 26-27
3.7
l.OxlO6
290
2,510
0.10
Rain
June 4
0.2
8.8xl06
26,000
1,400,000
0.02
Rain
-------
TABLE 19. AVERAGE CONCENTRATIONS OF FC, FS, AND TC IN RUNOFF FROM THE ROCK CREEK
CHECK WATERSHED, 1977 WATER YEAR
Water
Event dates delivery Total C Fecal C Fecal S FC/FS Event type
(M^) (Average No./lOO ml)
1976
Dec.
26-27
82.9
Snowmelt/rain
1977
Jan.
16-19
206.9
5,800
6,200
Snowmelt/rain
Feb.
8-10
12.2
24,600
500
4,900
0.1
Snowmelt/rain
Mar.
8-9
2.6
23,900
110
750
0.1
Rain/snow/rain
Mar.
19
<1.0
15,400
90
160
0.6
Mar.
27
<1.0
7,800
200
50
4.0
-------
TABLE 20. AVERAGE CONCENTRATIONS OF FC, FS, AND TC IN RUNOFF FROM THE ROCK CREEK
MAIN WATERSHED, 1978 WATER VEAR
Event dates
Water
delivery
Total C
Fecal C
Fecal S
FC/FS
Event type
(M3)
fAv/praop Nn /10D ml)
^ nv li aye mu • / ii/u in i /
1977
Oct. 30-Nov. 2
15.6
369,000
18,000
46,000
0.39
Ra in
Nov. 8
22.9
677,000
74,000
633,000
0.12
Pond draining
Nov. 13-16
26.0
185,000
9,000
10,900
0.90
Rain
Nov. 25-30
304.5
524,000
10,000
8,500
1.18
Snowmelt/rain
Dec. 1-4
172.3
161,000
8,000
12,000
0.67
Snowmelt/rain
Dec. 6-7
107.2
223,000
8,000
12,000
0.67
Snowmelt/rain
Dec. 10-15
6,717.9
163,000
3,800
3,800
1.00
Rain
1978
Jan 5-9
5,874.6
32,000
250
340
0.74
Snowmelt/1imited rain
Feb. 3-7
6,699.4
19,700
170
200
0.85
Snowmelt/rain
Feb. 26-Mar. 2
1,417.5
21,800
70
110
0.91
Snowmelt/rain
Mar. 8-9
1,067.6
11,100
60
80
0.75
Rain
Mar. 12-15
1,152.4
8,400
40
75
0.53
Snowmelt
Apr. 1-7
1,518.6
76,000
250
620
0.40
Rain/sleet/snow
Apr. 16
122.7
106,000
630
3,400
0.19
Snow/hai1/rain
Apr. 27-28
166.4
89,000
1,000
2,400
0.42
Rain
May 15-16
113.0
494,000
5,400
7,300
0.74
Rain
July 4
6.3
5,600,000
187,000
600,000
0.31
Rain
Total water
delivery 25,505.0
Base flow water
delivery and
bacteria con-
centrations 12,098.0 23,000 150 420 0.36
-------
TABLE
21. AVERAGE
CONCENTRATIONS OF FC,
FS, AND TC
IN RUNOFF FROM
THE ROCK CREEK
CHECK
WATERSHED,
1978 WATER
YEAR
Water
Event dates
delivery
Total C
Fecal C
Fecal S
FC/FS
Event type
/ m3 }
I Avpranp Nn 1 100 ml \
I » 1 /
1977
Nov. 25-27
14.9
702,000
210
5,900
0.04
Snowmelt/rain
Dec. 1-3
15.3
248,000
130
7,400
0.02
Snowmelt/rain
Dec. 6-7
4.0
308,000
50
8,400
0.01
Snowmelt/rain
Dec. 10-16
143.0
116,000
100
2,500
0.04
Rain
1978
Jan 5-9
89.3
26,000
30
220
0.14
Snowmelt/1imited rain
Feb. 2-8
81.6
14,900
10
100
0.10
Snowmelt/rain
Feb. 26-Mar. 1
7.2
24,600
5
20
0.25
Snowmelt/rain
Mar. 8-9
9.6
16,100
4
30
0.13
Rain
Mar. 12-15
5.5
13,700
10
20
0.50
Snowmelt
Apr. 1-7
23.6
205,000
40
2,400
0.02
Rain/sleet/snow
Apr. 16
2.5
149,000
35
10,400
0.003
Snow/hai1/rain
Apr. 27-28
4.2
143,000
200
10,700
0.02
Rain
May 15-16
5.8
481,000
160
43,000
0.003
Rain
Total water
delivery
407.0
-------
TABLE 22. AVERAGE CONCENTRATIONS OF
FC, FS. AND TC
IN RUNOFF
FROM THE ROCK
CREEK 1
MAIN WATERSHED, 1979 WATER
YEAR
Water
Event dates
delivery
Total C
Fecal C
Fecal S
FC/FS
( m3 \
- (Avprflop Nn /TOO ml ^
\ "• /
\riv ci aye iiw • / ivv ii11 y
1978
Nov. 4
0.9
1,522,000
26,800
62,300
0.43
Nov. 17
6.0
313,300
24,500
72,200
0.34
Nov. 30-Dec. 4
65.6
37,800
800
4,600
0.17
Dec. 11
96.7
30,300
500
6,500
0.09
Dec. 23-24
68.4
22,700
1,100
1,000
1.10
1979
Feb. 6-7
51.4
101,700
300
6,300
0.04
Feb. 9-14
12,523.2
58,900
200
2,400
0.08
Feb. 18-20
1,254.6
18,000
80
500
0.16
Feb. 25-28
5,012.5
7,900
70
1,200
0.06
Mar. 4-8
4,968.2
5,600
60
400
0.15
Mar. 15-18
1,066 .5
38,300
50
400
0.13
Mar. 27-28
532.2
27,200
100
1,000
0.10
Apr. 2-4
1,001.4
10,600
40
200
0.20
Apr. 6-10
2,510.2
10,000
90
400
0.23
Apr. 12-13
675.4
2,600
300
200
1.50
Apr. 16-17
631.8
10,700
90
700
0.13
Apr. 23-24
623.5
26,200
200
700
0.29
May 4-9
3,926.8
37,800
1,200
2,100
0.58
Total water
delivery
35,015.0
Base flow water
delivery and
bacteria con-
centrations
5,618.0
21,900
120
420
0.29
-------
TABLE 23. AVERAGE CONCENTRATIONS OF FC, FS, AND TC IN RUNOFF FROM THE ROCK
CREEK CHECK WATERSHED, 1979 WATER YEAR
Event dates
Water
delivery
Total C
Fecal C
Fecal S
FC/FS
(M3)
1978
Dec. 3-4
10.2
68,500
8
1,500
.005
Dec. 11
18.9
31,200
4
1,500
.003
Dec. 23-24
11.1
20,800
3
1,500
.002
1979
Feb 6-7
2.9
53,500
2
3,600
.006
Feb. 9-15
170.1
22,600
2
1,300
.002
Feb. 17-20
12.1
7,400
2
360
.006
Feb. 25-28
42.4
9,000
4
830
.005
Mar. 4-7
15.8
3,700
3
450
.007
Mar. 16
1.7
16,000
3
1,300
.002
Mar. 27-28
6.4
16,400
2
4,400
.001
Apr. 2-4
4.7
8,000
2
320
.006
Apr. 6-9
15.1
20,700
13
640
.020
Apr. 12-13
4.2
2,900
9
1,800
.005
Apr. 16-17
3.9
30,900
5
1,800
.005
Apr. 24
6.7
40,200
2
1,500
.001
May 4-6
43.9
116,000
13
3,600
.004
Total water
delivery
370.0
-------
TABLE 24. BACTERIOLOGICAL WATER QUALITY STANDARDS (SURFACE WATERS)*
Water use Total C Fecal C
(No./lOO ml)
Recreation
Primary contact 1,000 200
Partial contact 5,000 1,000
Public water supply 10,000 2,000
* U.S. Department of Interior, Federal Water Pollution Control Adminis-
tration. 1968. A report of the Committee on Water Quality Criteria.
Washington, D.C.
60
-------
TABLE 25. WATER QUALITY PARAMETER CONCENTRATION RESPONSES TO STREAMFLOW
Parameter
Type of runoff
event
Time of year
Response to streamflow
Bacteria, oxygen
demands, N and P
nutrients
Rainfal1
Fall and spring
Direct response to streamflow
changes with successively
smaller peak concentration
II
Snowmelt or frozen
ground rainfall
Winter
Little or inverse response
to streamflow
II
Mixed (snowmelt
followed by
rainfal1)
Fall, winter,
and spring
Little response during snow-
melt. Direct response to
rainfal 1
II
Snowmelt or
rainfal1
Late winter
and/or
Little response to streamflow
changes
Specific conductance,
pH, CI, Na, K, Ca, Mg
Snowmelt or
rainfal1
Fall, winter,
and spring
Inverse response to streamflow
-------
TABLE 26. AVERAGE PERCENT FECAL COVERAGE IN THE DRAINAGE SAMPLED
WITHIN THE STUDY WATERSHED, NOV. 4, 1978
Samp]ing
site No.
Fecal coverage
Drainage runoff areas percent area
1
Sacrifice (lower) pasture (plus rest
of grazed main watershed)
20*
2
Ungrazed (check) watershed
0
11
Southeast area just above main sampling station
NS
12
Northeast area just above main sampling station
0.7
13
All of the grazed watershed except the southeast,
northeast and sacrifice areas
2.6
14
North pasture area draining into large gulley
channel
0..9
15
Northwest pasture area
3 J
16
Southwest pasture area
2.2
17
Woodland area
1.8
IS
Logged area (outside of fenced cattle grazed
area, horses however were grazed here)
NST
*Total remainder of watershed averaged 1.4 percent.
* NS = Not sampled.
62
-------
TABLE 27. WITHIN WATERSHED INDICATOR BACTERIA RESULTS*
Sampling
site
Date
T ime
Flow
(1/sec)
Fecal
coliforms
Feca 1
strep
FC/FS
No/100 ml
18
6
Dec
77
1535
_+
4,000
17,000
0.24
16
6
Dec
77
1530
—
10,000
28,000
0.36
14
6
Dec
77
1520
-
18,400
23,000
0.80
13
6
Dec
77
1515
—
12,800
20,000
0.64
1
6
Dec
77
1500
1.41
11,000
75,000
0.44
2
6
Dec
77
1600
0.05
70
6,000
0.01
18
13
Dec
77
1300 *
1,500
2,000
0.75
17
13
Dec
77
1300
—
300
2,200
0.14
16
13
Dec
77
1300
—
300
3,100
0.10
15
13
Dec
77
1300
-
320
4,700
0.07
74
13
Dec
77
1300
-
1,700
7,400
0.23
13
13
Dec
77
1300
—
480
5,400
0.09
12
13
Dec
77
1300
—
700
3,500
0". 20
11
13
Dec
77
1300
—
200
2,700
0.30
1
13
Dec
77
1300
42.10
800
2,700
0.30
2
12
Dec
77
1300
0.01
4
400
0.01
18
15
Mar
78
1222
410
100
4.10
17
15
Mar
78
1216
10
30
.03
16
15
Mar
78
1212
30
215
.14
15
15
Mar
78
1211
60
70
.86
14
15
Mar
78
1208
50
105
0.48
13
15
Mar
78
1207
90
150
0.60
12
15
Mar
78
1205
60
35
1.71
11
15
Mar
78
1204
10
10
1.00
1
15
Mar
78
1200
10.24
155
150
1.03
2
15
Mar
78
1200 '
0.70
-
30
-
18
13
Feb
79
1050
36
1540
0.02
17
13
Feb
79
1100
-
12
460
0.03
16
13
Feb
79
1105
—
56
680
0.08
15
13
Feb
79
1107
—
16
640
0.02
14
13
Feb
79
1110
—
32
620
0.05
13
13
Feb
79
1113
—
36
600
0.06
12
13
Feb
79
1115
-
40
1720
0.05
11
13
Feb
79
1120
—
4
760
0.01
1 •
13
Feb
79
1200
73.27
230
460
0.50
2
13
Feb
79
1200
0.68
0
1140
-
18
27
Feb
79
1136
___
_
300
17
27
Feb
79
1140
—
—
100
-
(continued)
63
-------
TABLE 27 (continued)
Samp ling
site
Date
Time
Flow
(1/sec)
Fecal
coliforms
Fecal
strep
FC/FS
No/100 ml
16
27 Feb
79
1143
__
__
370
15
27 Feb
79
1145
-
-
250
14
27 Feb
79
1 130
—
-
210
13
27 Feb
79
1152
-
-
370
_
12
27 Feb
79
1155
-
12
370
0.04
11
27 Feb
79
1154
—
4
300
0.01
1
27 Feb
79
1200
13.0
40
370
0.11
2
27 Feb
79
1300
0.18
0
160
-
18
6 Apr
79
1010
_
225
1,800
0.13
17
6 Apr
79
1025
-
10
no
0.09
16
6 Apr
79
1030
-
160
600
0.27
15
6 Apr
79
1035
—
55
490
0.11
14
6 Apr
79
1040
-
550
970
0.57
13
6 Apr
79
1045
—
130
830
O.lo
12
6 Apr
79
1050
—
545
1,290
0.42
11
6 Apr
79
1055
—
70
620
0.11
1
6 Apr
79
1100
10.96
205
1,170
0.18
2
6 Apr
79
1125
0.14
0 .
370
-
18
4 May
79
1200
2,700
8,000
0.34
17
4 May
79
1202
-
90
4,900
0.02
16
4 May
79
1205
-
2,230
20,000
0.11
15
4 May
79
1208
' -
200
1 ,900
0.11
14
4 May
79
1210
-
50
100
0.50
13
4 May
79
1210
—
2,400
15,000
0.16
12
4 May
79
1214
-
1,400
19,000
0.07
11
4 May
75
1212
-
1,590
18,000
0.09
1
4#May
79
1215
2.36
5,300
12,000
0.44
2
4 May
79
1215
0.01
5
7,900
0.01
* See Figure 2 for sampling locations and associated runoff areas.
^ No flow estimate made.
^ Time approximately only.
64
-------
TABLE 28. WITHIN WATERSHED N AND P RESULTS*
Sampling
site
Date
T ime
Flow
(1/sec)
(mg/1)
Total N
(mg/1)
Ortho-P
(mg/1)
Total-P
(mg/1)
18
6
Dec
77
1535
-
0.03
1.30
0.31
0.53
16
6
Dec
77
1530
—
0.03
1.20
0.40
0.49
14
6
Dec
77
1520
—
0.11
1.70
0.09
0.31
13
6
Dec
77
1515
—
0.83
2.40
0.03
0.79
1
6
Dec
77
1500
1 .41
0.50
0.93
0.16
0.27
2
6
Dec
77
1600
0.05
0.03
1.20
0.02
0.22
18
13
Dec
77
1300 f
_
0.78
3.60
0.22
. 2.10
17
13
Dec
77
1300
—
0.12
1.6
0.16
0.77
16
13
Dec
77
1300
—
0.01
1.2
0.35
0.77
15
13
Dec
77
1300
—
0.13
1.8
0.13
0.66
14
13
Dec
77
1300
—
0.07
2.5
0.09
0.21
13
13
Dec
77
1300
—
0.55
3.3
0.28
1.60
12
13
Dec
77
1300
—
0.14
1.4
0.07
0.51
11
13
Dec
77
1300
—
0.58
1.5
0.39
0.53
1
13
Dec
1300
42.10
0.58
3.5
0.23
1.30
2
12
Dec
77
1300
0.01
0.28
0.7
0.06
0.23
18
15
Mar
78
1222
__
0.43
4.3
0.12
2.40
17
15
Mar
78
1216
-
0.12
1.6
0.14
0.65
16
15
Mar
78
1212
—
0.01
—
0.15
0.38
15
15
Mar
78
1211
-
0.01
—
0.08
0.20
14
15
Mar
78
1208
—
0.06
1.0
0.10
0.26
13
15
Mar
78
1207
—
0.07
1.4
0.09
0.72
12
15
Mar
78
1205
—
0.02
—
0.02
0.14
11
15
Mar
78
1204
—
0.01
0.41
0.09
0.13
1
15
Mar
78
1200
10.24
0.10
1 .40
0.07
0.28
2
15
Mar
78
1200
0.20
0.05
0.55
0.01
0.15
18
13
Feb
79
1050
_
3.78
5.59
0.26
0.48
17
13
Feb
79
1100
—
0.36
1.36
0.18
0.40
16
13
Feb
79
1105
—
3.13
4.78
0.40
0.76
15
13
Feb
79
1107
—
0.83
2.54
0.24
0.38
14
13
Feb
79
1110
—
1.78
2.59
0.19
0.26
13
13
Feb
79
1113
-
1.97
3.32
0.44
0.57
12
13
Feb
79
1115
-
1.10
2.22
0.23
0.35
11
13
Feb
79
1120
—
0.15
0.99
0.32
0.41
1
13
Feb
79
1200
72.27
1.63
3.02
0.27
0.57
2
13
Feb
79
1200
0.68
0.18
0.85
0.03
0.13
18
27
Feb
79
1136
1.21
1.82
0.14
0.28
17
27
Feb
79
1140
_
0.21
0.74
0.14
0.23
16
27
Feb
79
1143
-
1.08
1 .93
0.22
0.40
15
27
Feb
79
1145
0.34
1.17
0.12
0.18
(continued)
65
-------
TABLE 28 (continued)
Sampling
Flow
Total N
Ortho-P
Total-P
site
Date
Time -
—(1/sec)
(mg/1)
(mg/1)
(mg/1)
(mg/1)
14
27
Feb
79
1150
0.52
1.01
0.06
0.10
13
27
Feb
79
1152
-
0.76
1.56
0.21
0.37
12
27
Feb
79
1155
—
0.19
0.82
0.09
0.11
11
27
Feb
79
1154
—
0.50
1.17
0.23
0.40
I
27
Feb
79
1200
13.00
0.67
1.37
0.16
0.23
2
27
Feb
79
1300
0.18
0.25
0.86
0.01
0.05
18
6
Apr
79
1020
0.23
2.97
0.14
1.77
17
6
Apr
79
1025
-
0.04
0.82
0.10
0.30
16
6
Apr
79
1030
-
0.05
1.28
0.26
0.45
15
6
Apr
79
1035
-
0.08
1.15
0.05
0.08
14
6
Apr
79
1040
—
0.10
1.26
0.07
0.11
13
6
Apr
79
1045
—
0.08
1.19
0.25
0.30
12
6
Apr
79
1050
-
0.07
1.23
0.08
0.17
11
6
Apr
79
1055
—
0.06
1.43
0.11
0.18
1
6
Apr
79
1100
10.96
0.07
1.42
0.17
0.34
2
6
Apr
79
1125
0.14
0.14
1.90
0.10
0.28
Iff
4
May
79
1200
1.00
2.67
0.04
0.97
17
4
May
79
1202
—
0.14
1,27
0.07
0.37
16
4
May
79
1205
—
0.19
2.33
0.29
0.82
15
4
May
79
1208
-
0.11
1.61
0.12
0.26
14
4
May
79
1210
—
0.13
1.47
0.04
0.30
13
4
May
79
1210
-
0.12
2.29
0.15
0.74
12
4
May
79
1214
—
0.25
2.31
0.06
0.37
11
4
May
79
1212
—
0.16
2.77
0.09
0.46
1
4
May
79
1215
2.36
0.14
2.01
0.07
0.50
2
4
May
79
1215
0.20
0.34
2.26
0.07
0.30
* See Figure 2 for sampling locations and associated runoff areas.
+ Time only approximate.
-------
E
E
160
o 120
o
Q.
5 Q0
-------
cr>
00
E
E
c
o
600-
500-
400-
o
<1)
13
0)
13
E
3
O
o
<
300-
200
100-
Normal
(Potlatch, Id.)
(Record Began)
Oct Nov Dec Jan Feb Mar Apr May Jun
Figure 4. Accumulative daily precipitation and normal precipitation,
-------
§ 25
5 . 20
15
W& "0
° 0
sO
$ in 100
g § 50
«3 0
A A-/\ ^ h s k » Ka k
¦ ILr\ IV IU|UM
Nov Dec Jan Feb Mar
1976 1977
Figure 5. Runoff season hydrologic summary for main
watershed, 1976-77.
69
-------
c
o
.¦? E
-- E
o
4)
CL
II
tr
o
10
20
30
12
10
8
6
4
2
0
'WTI1
Jfc-lL
E
5 °~
o -C
c -tr
CO
d>
Q
vO
o 5?
(J~>
o
A
i nyr^.nr\A
Nov . Dec
1977
Jan
Feb
1978
Mar
Figure 6. Runoff season hydrologic summary for main
watershed, 1977-78
70
-------
c
o
o
0
o
E
10
Q.
n
£
20
CD
V
Q.
30
* *
O
r
E
20
3
E
10
(T
Xf'
vr i mr
traces
cn 9-
Nov Dec
1978
Jan
Feb Mar
1979
Figure 7. Runoff season hydrologic summary for main watershed,
1978-79.
71
-------
ro
_2 80
Streamflow
a) 60
jQ Q 6 a Q i Q
°° °o
o °
\Sediment
Concentration
o
0000 0600 1200 1800 0000 0600 1200 1800
12 Feb 79 13 Feb 79
Figure 8. Runoff hydrogranh from the main study watershed.
i7000
6000 ^
o>
E
5000 c
o
o
4000 ^
c
if)
0000
-------
2.00
25
1.75
1.50
Streamflow
1.00
0 o
0.75
o o
Sediment
Concentration
0.50
-o
0.25
1800 0000
1800 0000 0600
0000 0600
1200
1200
12 Feb 79 13 Feb 79
Figure 9. Runoff hydrograph from the check study watershed.
-------
Soil Moisture, % by Volume
Ground 0
Surface °f
JQ Jr
-------
1.00
0.50
0.00
Well 3
-0.50
Well
P - 1.00
CL
Well 5
Well 6
-2.00
-2.50
Well 2
Well 4
-3.00
Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep
1977 Water Year
Figure 11. Rock Creek watershed groundwater levels, 1976-77.
-------
0.50
0.00
Well 3
-0.50
v
-------
0.50
0.00
Well 3
-0.50
s
Well
-1.00
-1.50
Well 5
.Well 6
Q.
£ -200
-2.50
Well 2
Well 4
-3.00
Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep
1979 Water Year
Figure 13. Rock Creek watershed groundwater levels, 1978-79.
-------
CO
"O
Q)
2 120
= 110
a 100
90
80
c 70
S 60
X
O
O
o
af
v_
3
O
»_
a)
Q.
E
¦*—
a
£
18
16
14
12
10
8
6
4
2
0
,'\ S 1978, ^
1 ' 1979
Rock Creek Main Watershed
t.
i:\
•: i-. • s-inifi: lUSA I
*/i
w;
TWii'l . fVA !
I977
I20
110
100
90
80
70
60
18
16
14
12
10
8
6
4
2
0
Oct Nov Dec Jan Feb Mar Apr May Jun Jul
Figure 14. Water temperature and dissolved oxygen for the main watershed.
-------
o
CO
TJ
d)
O 120
2 110
100
90
80
c 70
60
>%
x
O
1979
Rock Creek Check Watershed
a)
o
4
2
0
8
6
4
2
0
Nk P-j
' N
Oct Nov Dec Jan Feb Mar Apr May Jun Jul
Figure 15. Water temperature and dissolved oxygen for the check watershed.
-------
to
Streamflow
£= 0.8
400 7=
300 2
0.6
Fecal Streptococci
(FS.)
0.4
Fecal Colliforms
. J FG)
:P X
0.2
100
cr-
2400
1800
1200
2400 0600
1800
1200
0000 0600
7 Mar 77 8 Mar 77
rigure 16. Streamflow hydrograph, fecal streptococci and coliform concentrations,
Rock Creek main watershed.
-------
CD
CO
£
o
H—
£
o
<1>
CO
Streamflow
Specific
Conductance
(SC)
W -4
0000 0600 1200 1800 2400 0600 1200 1800 2400
I Dec 77 2 Dec 77
Figure 17. Streamflow hydroqraph and specific conductivity, Rock Creek main watershed.
-------
80
70
60
0.5
50
£
o
Nitrate Nitrogen
—(NO,"-N)
0.4 _
^ 40
o
cu
£ 30
0.3
CD
0.2
20
Streamflow
0000 0600
1200
1200
1800
2400
1800
2400
0600
3 Feb 78 4 Feb 78
Figure 18. Streamflow hydrograph and nitrate concentrations, Rock Creek main watershed.
-------
30
if)
0.5
0.4 5?
^ 20
£
o
<1)
Streamflow
if)
— o-
-o
-o
2400
1800
1200
0600
1800
2400
0000
1200
0600
5 Jan 78 6 Jan 78
Figure 19. Streamflow hydrograph and ortho-phosphate concentrations, Rock Creek main
watershed.
-------
40
30
20
10
-Streamflow
~r0
A
Chemical
Oxygen Demand /
a (COD) ^
' N<
v\
\
S.
Vq__.
50
40 —
30
o>
E
a
20 O
o
10
0
0000 0600 1200 1800 2400 0600 1200 1800 2400
5 Jan 78
Figure 20. Typical water quality parameter concentration response, COD, to streamflow
during snowmelt, Rock Creek main watershed.
-------
7 r
00
co 2
Snow melt
(Frozen Ground)
Runoff
Streamflow
—~—
0
0000
Rainfall
Runoff
1.0 o>
0.8 "
Total Phosphorus
0.6 9-
0600 1200
6 Dec 77
1800
2400 0600
1200
7 Dec 77
o
0.2 H
2400
Figure 21. Typical water quality parameter response, total P, to streamflow during a mixed
snowmelt and rainfall event, Rock Creek main watershed.
-------
^MAIN
WATERSHED
(21.5 ha)
Open
Pasture
Weather
Station
Spring.?
Woodland ^
Pasture
Logged Pasture^
J,
*MC»SHED
LOCUTION
^ Raingage
^ Soil Moitiurs
B Groundwottr
*> Striamgogc
•920"" Contour, molert
— — Wol«r«htd Boundary
*—* Fartcc
— lnt«rmlttant Stream
Fl«ld Boundary
C::j Smoit Pond
/-TpCHECK
' I WATERSHED
(0.9 ha)
Site No.
Location
Runoff Area
1
Main station
Entire grazed watershed
2
Check station
Ungrazed watershed
11
Just south & above main stream
channel weir pond
Southeast pasture
12
Just north & above main stream
channel weir pond
Northeast pasture
13
Outlet of main stream channel pond
Woodland, no. & so. pasture
14
Large gulley channel in north pasture
North pasture
15
Above and north of pond
Northeast pasture
16
Above and south of pond
Southeast pasture
17
Main stream channel below woods
Woodland pasture
18
Upper southwest pasture
Logged pasture
Figure 22. Location and description of sampling sites within the watershed.
86
-------
1
2
3
4
5
6
7
8
9
10
11
12
REFERENCES
Asmussen, L. E., J. M. Sheridan, and C. V. Booram, Jr. Nutrient
Movement in Streamflow from Agricultural Watersheds in the Georgia
Coastal Plain. TRANSACTIONS of ASAE 22:809-815. 1979.
Buckhouse, J. C., and F. 6. Gifford. Water Quality Implications of
Cattle Grazing on a Semiarid Watershed in Southeastern Utah. J. Range
Manage., 29:109-113. 1976.
Chichester, F. W., R. W. Van Keuren, and J. L. McGuinness. Hydrology
and Chemical Quality of Flow from Small Pastured Watersheds. II.
Chemical Quality. J. Environ. Qual., 8:167-171. 1979.
Doran, J. W., and D. M. Linn. Bacteriological Quality of Runoff water
from Pastureland. Appli. Environ. Microbiol., 37:985—991. 1979.
Geldreich, E. E. Fecal Coliform and Fecal Streptococcus Density
Relationships in Waste Discharges and Receiving Waters. Crit. Rev.
Environ. Control, 6:349-369. 1976.
Geldreich, E. E. Current Status of Microbiological Water Quality
Criteria. ASM News 47:23-27. 1981.
Hendricks, C. W. and S. M. Morrison. Multiplication and Growth of
Selected Enteric Bacteria in Clear Mountain Stream Water. Pergammon
Press, Great Britain. Water Res. 1:567-576. 1967.
Kibbey, H. J., C. Hagedorn, and E. L. McCoy. Use of Fecal Streptococci
as Indicators of Pollution in Soil. Appl. and Environ. Microbiol.
35:711-717. 1978.
Kilmer, V.J., J. W. Gilliam, J. F. Lutz, R. T. Joyce, and C. D. Eklund.
Nutrient Losses from Fertilized Grassed Watersheds in Western North
Carolina. J. Environ. Qual., 3:214-219. 1974.
Kunkle, S. H. Concentrations and Cycles of Bacterial Indicators in Farm
Surface Runoff. In: Proc. Cornell Waste Manage. Conf.. Syracuse, N.Y.
Jan. 19-21, 1970. pp. 49-60.
Menzel', R. G., E. D. Rhoades, A. E. Olness, and S. J. Smith.
Variability of Annual Nutrient and Sediment Discharges in Runoff from
Oklahoma Cropland and Rangeland. J. Environ. Qual., 7:401-405. 1978.
Milne, C. M. Effect of a Livestock Wintering Operation on a Western
Mountain Stream. Trans. Am. Soc. Agric. Eng., 19:749-752. 1976.
87
-------
13
14
15.
16,
17
18,
19
20,
21.
22
23,
24-,
25.
Olness, A., S. J. Smith, E. D. Rhoades, and R. G. Menzel. Nutrient and
Sediment Discharge from Agricultural Watersheds in Oklahoma. J.
Environ. Qual., 4:331-336. 1975.
Olson, R. A., E. C. Seim, and J. Muir. Influence of Agricultural
Practices on Water Quality in Nebraska: A Survey of Streams,
Groundwater and Precipitation. Water Res. Bull., 9:301-311. 1973.
Robbins, J. W. D., D. H. Howells, and G. J. Kris. Stream Pollution from
Animal Production Units. J. Water Pollut. Control Fed., 44:1536-1544.
1972.
Rycert, R. C., and G. R. Stephenson. Atypical E^ coli in Streams.
Appl. and Environmen. Microbiol. (In press). 1981.
Schepers, J. S., D. R. Anderson, G. E. Schuman, E. J. Vavricka, and H.
D. Wittmuss. Agricultural Runoff in the Midwest. J. Water Poll.
Control Fed. 44:1536-1544. 1980.
Schuman, G. D., and R. E. Burwell. Precipitation Nitrogen Contribution
Relative to Surface Runoff Discharges. J. Environ. Qua!., 3:366-368.
1974.
Skinner, Q. D., J. C. Adams, P. A. Richard, and A. A. Beetle. Effect of
Summer Use of a Mountain Watershed on Bacterial Water Quality. J.
Environ. Qual. 3:329-335. 1974.
Stephenson, G. R., and R. C. Rycert. Bottom Sediment: A Reservoir of
Escherichia coli in Rangeland Streams. J. Range Manage. (In press).
mr.
Stephenson, G. R. and L. V. Street. Bacterial Variations in Streams
from a Southwest Idaho Rangeland Watershed. J. Environ. Qual.
7:150-157. 1978.
Thomas, G. S., apd J. D. Crutchfield. Nitrate-Nitrogen and Phosphorus
Contents of Streams Draining Small Agricultural Watersheds in Kentucky.
J. Environ. Qual. 3:46-49. 1974.
Timmons, D. R., and R. F. Holt. Nutrient Losses in Surface Runoff from
a Native Prairie. J. of Environ. Qual. 6:369-373. 1977.
Timmons, D. R., E. W. Verry, R. E. Burwell, and R. F. Holt. Nutrient
Transport in Surface Runoff and Interflow from an Aspens-Birch Forest.
J. Environ. Oual. 6:188-192. 1977.
Van Donsel. D. J., E. E. Geldreich, and N. A. Clarke. Seasonal
Variations in Survival of Indicator Bacteria in Soil and Their
Contribution to Storm-Water Pollution. Appl. Microbiol. 15:1362-1370.
1967.
88
-------
APPENDIX A
Daily Observed Precipitation, Runoff, and Sediment Discharge
89
-------
.TABLE A-l. DAILY SUMMARY OF PRECIPITATION, RUNOFF, AND SEPIMENT DISCHARGE FOR ROCK CREEK MAIN WATERSHED
P = Daily Precipitalion, mm (Main Watershed Weighing Gage)
Q = Dai ly Runoff, mm
S - Uaily Sediment, kg/ha
Oec 76'-- Jan 77— Feb 77 Mar 77
Day
P
Q
S
P
0
S
P
Q
S
P
Q
S
1
.5
2.0
.032
.008
2
.5
.001
3/
.019
3
1.5
.011
.019
4
.5
.008
.016
5
.009
.016
6
.012
.018
7
8
1.0
.018
.110
.152
11.0
7.0
.072
.092
.119
.120
9
11
.132
.159
8.0
.124
.125
10
.5
.5
.198
.338
.016
.003
11
.5
.013
.5
.044
.018
.016
12
.5
.006
4.0
.123
1.0
.018
13
.007
1.0
.029
6.0
.005
14
.001
4.0
.013
1.0
.015
15
.002
1.0
.006
.018
1.0
.C41
.011
16
.007
3.5
1.485
2.041
.019
.041
.007
17
.004
y
2.372
4.649
.023
1.0
.026
.005
18
2.0
4.248
31.557
.021
3.0
.036
.005
19
.149
.266
.016
4.0
.066
.021
20
.075
1.0
.020
.5
.028
.006
21
.021
5.5
.039
.025
22
.021
1.0
.034
.5
. C16
23
10.5
.5
.036
.013
1.0
.022
24
.008
.014
.007
1.0
.013
25
6.5
.007
2.5
.008
.009
26
1.5
.202
.175
.025
1.0
.018
21
.5
.547
.718
2.5
.025
8.0
.048
.022
28
.006
5.0
.086
.022
.026
.004
29
.013
30
.008
31
1.5
.010
Total
20.00
0.810
(.735)5/
.893
21.0
8.427
(8.054)
38.513
19.5
1.062
(0.482)
.689
57.0
.926
(.404)
.456
JVbelfort weighing gage installed at weather station site.
|VGage moved to mid-watershed site.
2'wind shield added to gage.
i/Values accumulated where * appears due to clock stoppage.
^Estimated surface runoff only.
-------
TABLE A-l (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Apr 77 Kay 77 jun 77 _—Jul 77
Day P QS PQ S PQ S PQS
1
.5
.011
3.0
6.0
2
.008
11.5
.006
.006
3
.006
3.0
.010
.006
1 .5
4
.004
.001
2.5
5
.003
.5
6
7
1.5
8
1.0
5.0
9
10
5.0
.008
11
.002
12
6.5
.5
13
.020
o
o
C\j
1.5
14
.002
3.0
.002
15
.5
.005
.5
16
0.0
.008
1.0
17
6.5
.010
.002
2.0
18
12.5
.045
.032
8.5
19
.5
.003
.5
20
.5
21
22
23
5.5
.005
24
-.5
1.5
'25
4.5
26
8.5
.016
.016
27
1.0
.001
28
2.5
.005
29
30
31
Total
9.5
.067
.200
67.0
.113
.062
17.5
.001
17.5
(.018)
(.077)
(.001)
-------
TABLE A-l (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Aug 77 Sep 77 Oct 77 mov 77
Day P Q S P. Q S P Q S P Q S
]
7.5
.017
.021
2
1.0
1.5
.003
3
4.0
4
1.5
.002
5
.5
2.0
.008
6
1 .5
.003
7
.5
1.0
.002
S
.5
.107
5.279
9
3.0
.018
.006
10
.5
.016
11
.004
12
.5
.001
13
.5
6.0
.028
.007
14
7.0
.0^0
.018
15
4.5
.037
.003
16
2.5
.006
17
.5
2.5
.003
18
.007
19
6.0
20
21
2.5
22
2.0
5.5
23
3.5
10.5
24
10.0
9.5
2.0
25
2.0
7.0
15.5
1.170
.710
26
33.0 .001
.5
.076
.011
27
1.5
2.5
5.5
.077
.01.9
28
1.0
8.0
1.0
.036
.005
29
6.5
1.5
10.0
3.0
.048
.018
30
11.5
2.5
7.0 .004
.017
.010
31
.5 .049
.084
Total
.c*
O
O
o
47.0
31.0 .053
.101
78.5
1.729
6.097
(.001)
(.015)
(1.599)
1977
Annual Totals: P =
340.0 mm; 0 = H .4 mm (9A
3 mm): S = 40.8 Kg/ha.
-------
TABLE A-l (continued)
P = Daily Precipitation, inm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Dec 77 jan 78 peb 78 Mar 78
Day
P
Q
S
P
Q
S
P
Q
S
P
Q
S
1
15.0
.355
.385
1.0
.101
.004
5.0
.155
.007
.5
1.264
.225
2
7.0
.282
.359
1.5
.100
.003.
4.0
.730
.134
.678
.283
3
5.0
.115
.117
10.5
.096
.003
6.750
1.7.909
1.0
.309
.076
4
.5
.049
.00b
.5
.229
.019
5.363
3.431
3.5
.94 2
.482
5
.5
.010
.001
6.0
6.062
8.522
3.577
1.059
1.0
1.389
.357
6
6.5
.399
.874
7.498
10.996
13.0
8.015
11.104
.824
.104
7
.100
.016
.5
5.207
.560
11.5
7.450
25.531
3.0
.792
.110
8
5.0
.020
.001
5.0
6.614
9.265
4 .491
1.796
8.0
2.652
2.152
9
.5
.032
.002
' .5
4.638
1.438
1.5
2.586
.273
1.0
2.312
.534
10
7.5
.897
.763
2.013
.379
1.340
.093
1.266
.3.78
11
15.0
4.790
28.948
1.5
1.259
.128
3.5
.880
.030
1.5
.925
.104
12
2.5
1.336
.331
2.5
1.196
.102
.750
.073
2.5
1.345
.208
13
*
12.040
220.001
1.0
.863
.127
.469
.052
5.5
1.483
.397
14
32.5*
7.167
86.672
1.0
1.644
.234
.5
.500
.052
4.5
1.141
.181
15
13.0
5.009
31.787
2.5
1.920
.590
4.5
.375
.019
.5
1.391
1.081
16
2.0
2.231
.488
2.0
1.927
.192
.423
.024
.852
.128
17
6.5
1.143
.168
2.5
1.589
.138
.452
.115
.504
.031
18
3.5
.825
.067
1.0
1.208
.076
1.5
.628
.083
.275
.025
19
.544
.035
1.0
.896
.066
.5
.851
.044
.186
.028
20
.293
.027
2.5
1.371
.117
.5
.580
.036
.136
.020
21
.274
.020
1.5
.960
.073
.354
.008
.107
.016
22
.5
.276
.019
.5
.619
.039
.244
.011
.088
.017
23
2.0
.241
.010
.5
.278
.018
1.0
.322
.025
3.5
.184
.130
24
.5
.180
.008
.127
.007
2.0
.326
.027
.5
.122
.017
25"
.161
.006
2.5
.154
.013
4.0
.859
.106
.5
.080
.009
26
.5
.149
.006
5.0
.159
.011
5.0
1.428
.297
.060
.008
27
.110
.004
.169
.012
5.0
1.543
.256
.039
.005
28
.115
.003
7.0
.161
.011
4.0
1.681
.390
.028
.003
29
3.0
.149
.006
1.0
.1 79
.019
.022
.002
30
11.5
.216
.006
1.0
.161
.010
.024
.002
31
.143
.004
4.5
.122
.006
3.0
.026
.037
Total
143.5
39.651
(36.832)
371.140
66.5
49.560
(35.560)
33.168
67.0
53.122
(43.289)
62.985
40.0
21.446
(6.059)
6.950
-------
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
IS
20
21
22
23
24
25
26
27
28
29
30
TABLE A-l (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Apr 78 May 78 Jun 78 Jul 78
P QS PQ S PQ S PQS
19.0
1.933
2.604
.033
.002
3.0
1.053
.269
.026
.001
1.0
.438
.053
1.5
.021
4.0
.592
.189
1.5
.022
.001
2.0
.724
.139
.021
.001
1.0
.501
.080
.011
.001
•ft
1.820
1.341
.006
*
.930
.120
.004
¦ft
.342
.288
3.0
.017
.001
¦ft
.127
.013
1.0
.011
.001
*
.083
.008
1.0
.009
7.0*
.061
.004
1.0
.006
.051
.004
1.5
.017
.001
4.0
1.0
.058
.008
2.5
.019
.001
.5
.053
.004
10.0
.107
.072
11.0
.571
.655
11 .0
.418
.769
] .0
.153
.016
.167
.017
.054
.004
.043
.003
.033
.002
.017
2.0
.100
.015
.006
.042
.002
9.5
.051
.083
2.5
.050
.006
.5
.036
.005
.041
.002
.5
.009
A
.020
.001
2.0 .
.018
.001
¦ft
.016
.006
ft
4.0
.026
.006
,5
.004
.001
13.0*
11.0
.288
.489
2.5
.017
.003
3.0
.487
.121
.5
.008
.001
1.0
.130
.013
.051
.004
73.0
10.028
6.460
50.0
1.130
.965
18.0
(4.491)
(.687)
*
19.0*
1.5
.5
.029 .014
•k
5.0*
.006
.003
.006
(.006)
.003 26.0
.029
(.029)
.014
-------
TABLE A-l (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Aug 78 Sep 78 Oct 78 Nov 78
Day P QS PQ S PQ S PQS
1
0.5
2
3
4.5
4
.5
3.5
.004
5
~
.002
6
*
.003
7
*
8
if
9
•k
10
k
11
25.5*
12
*
13
12.0*
*
14
~
15
13.0
k
16
~
2.5
17
~
5.5
.028
18
~
7.5
.004
19
.5
*
11.+
.006
20
3.0
1.0*
.006
21
1.0
1.0
~
.008
22
•k
.5
2.0*
.009
23
17.5*
.012
24
.012
25
.012
26
.009
27
10.0
.010
28
1.5
2.5
.012
29
.5
1.5
.010
30
5.0
.5
16.0
.034
31
1.0
Total
53.0
29.5
2.0
66.5
.181
(.048)
1978 Annual Totals: P = 676.0 mm: Q = 177.6 mm (118.6 mm); S = 487.9 Kg/ha.
-------
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
TABLE A-l (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Dec 78 Jan 79 Feb 79 Mar 79
p
Q
S
P
Q
S
P
Q
S
P
0
S
8.5
.032
o
o
no
*
.016
.002
1.514
.165
9.5
.018
*¦
.035
.007
.971
.134
.031
.002
5.0*
4.0
.012
1.0
.614
.135
13.0
.188
.023
.5
.010
6.0
3.233
1.106
.024
.001
.031
.003
5.5
5.898
2.849
.016
.001
7.0
.035
.010
.5
5.993
2.611
.013
3.5
.204
.056
2.0
5.610
2.259
.5
.012
.5
.041
.003
2.368
.468
4.5
.012
4.0
.296
.115
1.144
.172
4.0
.013
7.0
16.0
1.771
2.819
.723
.092
16.0
.449
.095
2.5
7.0
5.983
5.098
.635
.075
.5
.028
.001
3.0
31.0
17.370
116.523
.667
.070
.5
.015
.013
.5
4.0
4.5
28.246
4.567
424.354
2.700
.515
.427
.070
.057
.014
5.5
1.701
.626
3.0
.543
.104
.013
~
.012
2.5
1.081
.256
9.0
2.483
.662
2.0
.010
.5*
.012
2.0
1.081
.328
1.277
.150
6.0
.012
.011
4.0
2.732
.580
.656
.083
"ft-
.012
.5
.008
3.0
1.994
.279
.366
.040
2.0*
.012
2.5
.011
1.0
1.108
.176
.5
.223
.027
.018
15.0
.015
2.5
.733
.051
.146
.018
.021
¦A
.012
.5
.731
.086
.074
.008
6.0
.050
.012
*
.012
5.5
.359
.030
.044
.005
.268
.036
6.0*
.011
2.0
.606
.126
.025
.003
.5
.032
.001
.008
7.0
8.351
13.046
.020
.002
.013
1.0
.008
4.5
7.982
3.429
1.0
.028
.002
2.5
.012
2.5
.008
9.0
3.839
.952
14.5
1.104
1.148
~
.012
.5
.008
1.5
3.135
.667
3.0
1.371
.242
•A
.012
.009
.5
.705
.103
•ic
.008
2.0
.379
.046
~
.010
2.0
.390
.046
76.0
1.375
.174
56.0
.163
(.0)
123.0
94.050
(82.755)
572.322
50.5
40.146
(25.186)
12.953
-------
TAELE A-l (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Apr 79 May 79 Jun 79 Jul 7S
Day P QS PQ S PQ S PQS
1
1.5
.496
.055
2.5
.128
.024
2
9.0
1.740
.891
.5
.122
.005
3
~
1 .592
.172
.069
.001
4
.5*
1.325
.154
15.0
.610
.326
5
.707
.082
22.5
9.009
12.110
6
12.0
3.882
6.512
4.70k
.838
1.0
7
.5
2.291
.406
1.803
.150
8
3.0
1.321
.210
4.0
1.144
.143
9
5.0
2.752
1.070
.992
.062
10
.5
1.426
.178
.422
.013
11
1.011
.110
.210
.003
1.0
12
7.5
1.166
2.735
.143
.002
13
.5
1.975
1.668
.104
.002
.5
14
.5
.891
.082
.083
.001
15
.694
.075
.071
.001
16
7.0
.853
.872
.050
.001
2.0
17
3.0
2.085
1.509
.036
16.0
18
.767
.055
.032
1.5
19
.516
.021
.025
20
.5
.395
.017
.021
21
.255
.010
.014
22
.5
.283
.015
.009
23
5.0
.708
.146
1.0
.029
.001
24
8.0
2.109
1.818
.040
.001
25
.843
.090
.019
26
.395
.032
.011
1.1
27
.217
.013
.5
28
.142
.006
.5
29
.111
.004
.015
30
1.0
.122
.005
.016
1.1
31
65.0
33.070
19.013
46.5
19.929
13.720
24.1
(12.147) (14.650)
^Gage shut down (7/5) and removed from site.
1979 Annual Totals: P = 520.0 mm; Q = 188.9 mm (135.7 mm); S = 618.1 Kg/ha
-------
TABLE A-2, DAILY PRECIPITATION, RUNOFF, AND SEDIMENT DISCHARGE FOR ROCK CREEK CHECK WATERSHED
P = Daily Precipitation, mm (Main Watershed Weighing page)
Q = Dai ly Runoff, mm
S - Dai1y Sediment, kg/ha
- Dec 76 — Jan 77 Feb 77 Mar 77—
QS P Q S PQ S PQ
.5 2.0
.5 3/
1.5
Day
P
1
2
3
4
5
6
7
8
9
10
1/
11
.5
12
.5
13
14
15
16
17
18
15
20
21
22
23
10.5
24
25
6.5
20
1.5
27
.5
28
29
30
31
Total
20.0
.094
.062
.082
.056
11.0
.019
.544
.673
7.0
.068
.442
.314
8.0
.223
.362
.352
1.0
.5 .5
.5
4.0 1.0
1.0 6.0
1.0 1.0
1.0 .325 l.O
3.5 5.020 1.028
II 4.735 .763 1.0
2.0 12.704 8.479 3.0
.022 4.0
.084 1.0 .5
5.5
1.0 .5
.5 1.0
1.0
2.5
4.144 1.937 1.0
4.590 2.476 2.5 8.0
5.0
1.5
9.134 4.413 21.0 22.850 10.270 19.5 1.524 1.457 57.0 .310
l^Belfort weighing gage installed at weather station site.
UGage moved to mid-watershed site.
2/wind shield added to gage.
-------
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Apr 77 May 77 oun 77 Ju] 77
Day P QS P Q S PQ S P Q S
1
0.5
3.0
6.0
2
11.5
3
3.0
1.5
4
2.5
5
.5
6
7
1.5
8
.1.0
5.0
9
10
5.0
11
12
6.5
.5
13
1.5
14
3.0
15
.5
.5
16
2.0
1.0
17
6.5
2.0
18
12.5
8.5
19
.5
.5
20
.5
21
22
23
5.5.
24
.b
1.5
25
4.5
26
8.5
27
1.0
28
2.5
29
30
31
Total
9.5
67.0
17.5
17.5
-------
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/na
Aug 11 Sep 11
Day
P
Q
S
P
1
1.0
2
4.0
3
1.5
4
.5
5
6
7
8
9
10
11
12
13
14
15
lo
2.5
17
.5
18
19
6.0
20
21
2.5
22
2.0
23
3.5
24
10.0
9.5
25
2.0
'26 '
33.0
.023
27
1.5
28
1.0
8.0
29
6.5
1.5
30
11.5
2.5
31
31
Total
64.0
.023
47.0
1977 Annual Totals: P = 340.0 mm; Q = 33.9 nm; S = 16.1 Kg/ha.
-------
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Day
Oct 77- - -
P
¦ — No v 77
-Dgc 77_.
P
lan 78
P
Q S
Q.
S
P
PL L / /
Q
S
J O 11 / u •
Q
S
]
7.5
15.0
1.003
1.019
1.0
2
1.5
7.0
.595
.672
1.5
3
5.0
.077
.837
10.5
4
.5
.5
5
2.0
.5
6.0
3.704
1.082
6
1.5
6.5
.441
.493
2.139
.361
7
.5
1 .0
.5
.298
.035
8
.5
5.0
5.0
2.789
.678
9
3.0
.5
.5
.915
.135
10
.5
7.5
.948
.558
.132
.013
11
15.0
3.010
3.395
1.5
12
. 5
2.5
.232
.099
2.5
13
.5
6.0
*y
6.262
5.032
1.0
14
7.0
32.5*
3.054
2.484
1.0
.154
.035
15
4.5
13.0
2.062
1.184
2.5
.242
.107
16
2.0
.198
.028
2.0
.276
.051
17
2.5
6.5
2.5
18
3.5
1.0
19
1.0
20
2.5
.110
.025
21
.5
1.5
22
5.5
2.0
.5
23
10.5
.5
.5
24
2.0
25
¦7.0
15.5
1.499
.883
.5
2.5
26
c
.011
.012
5.0
27
2.5
5.5
.123
.094
28
1.0
3.0
7.0
29
10.0
3.0
11.5
1.0
30
7.0
. 3.0
1.0
31
.5
4.5
Total
31.0
78.5
1.633
.989
143.5
17.882
15.801
66.5
10.759
2.522
^Values accumulated where * appears due to clock stoppage.
-------
Da
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
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Feb 70--"--—-- Mar 78 —'—Apr 78 May 78
P QS PQ S PQ S PQS
5.0
.5
.121
.018
19.0
1.433
1.259
4.0
.694
.324
3.0
.132
.064
3.451
1.380
1.0
1.0
1.5
.353
.062
3.5
.088
.029
4.0
.132
.056
1.5
.110
.046
1.0
.121
.038
2.0
.099
.044
13.0
2.051
1.326
1.0
11.5
2.348
1.624
3.0
~
.805
.241
.331
.064
' 8.0
.838
.416
it
1.5
.110
.028
1.0
.209
.060
•k
3.0
*
1.0
3.5
1.5
A
1.0
2.5
.110
.023
7.0*
1.0
5.5
.309
.070
1.5
.5
4.5
1.0
2.5
4.5
.5
.209
.070
.5
10.0
11.0
.276
.160
1 1.0
1.0
1.5
C
.044
.013
0 J
.5
2.0
9.5
2.5
.5
1.0
3.5.
.5
2.0
.5
2.0
4.0
.055
.012
.5
5.0
.265
.069
4.0
.5
5.0
.198
. 02 if
11.0
.154
.087
2.5
4.0
.198
.032
3.0
.331
.178
.5
.650
>18
3.0
67.0 10.208 5.005 40.0 2.005 .724
73.0 3.362
2.089
50.0 .650 .518
-------
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Jun 78 Jul 78 Aug 78 Sep 78
Day P QS PQ S PQ S PQS
1
*
2
*
3
~
4
19.0*
.5
5
~
6
~
7
*
8
~
9
1.5
~
10
.5
*
11
22.5*
1?
~
13
4.0
12.0*
~
14
~
15
*
13.0
*
16
5.0*
*
17
*
18
•A
IS
.5
•k
20
3.0
*
21
1.0
1 .0*
22
~
1.0
23
~
17.5*
24
~
S?5
*
26
13.0*
27
28
1.0
29
1.5
30
5.0-
31
1.0
Total
18.0
26.0
53.0
29.5
1978 Annual Totals: P - 676.0 mm; Q = 16.5 mm; S = 27.6 Kg/ha.
-------
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
25
30
31
TABLE A-2 (continued)
P = Daily Precipj^t jpn, inm (Main Watershed Weighing Gage)
Q = Daily f
-------
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
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Feb 79 Mar 79 Apr 79 May 79
PQ S PQ S PQ S PQ
4.0
.5
7.0
3.5
.5
4.0
16.0
7.0
31.0
4.5
.015
.310
.607
1.949
2.679
6.184
6.973
.282
.070
.014
.131
.268
.364
.355
.700
.632
.026
.007
1.5
2.5
.064
.009
9.0
.132
.042
.5
1.0
*
.375
.244
6.0
.717
.168
.5 *
.010
.002
15.0
.058
5.5
.805
.097
22.5
4.195
.5
.111
.009
12.0
1.300
.933
.579
2.0
.108
.024
.5
.020
.006
3.0
4.0
5.0
.340
.242
.5
'.5 .163
.5 .292
.5
3.0
123.0 25.064 3.446
.5
2.0
2.0
50.5
2.691
.881
1.0
65.5
.241
.259
2.5
9.0
.185
.095
7.0
.004
.009
2.0
.077
.011
3.0
.426
.643
4.0
.938
.167
3.0
.295
.042
1.0
.018
.002
.5
.5
2.5
.5
.5
5.5
5.5
1.0
2.0
8.0
.740
.530
7.0
2.730
.497
4.5
1.186
.135
1.0
9.0
.653
.088
14.5
.519
.407
.5
1.5
.098
.007
3.0
.182
.072
.5
3.838 3.151 46.5 4.832
-------
TABLE A-2 (continued)
P = Daily Precipitation, mm (Main Watershed Weighing Gage)
Q = Daily Runoff, mm
S - Daily Sediment, kg/ha
Jun 79 jui 79
Day
P
1
2
3
4
5
6
1.0
7
8
9
10
11
1.0
12
13
.5
14
15
16
2.0
17
16.0
18
l.b
19
20
21
22
23
24
25
26
1.0
27
28
29
30
1.0
31
Total
24.0
Gage shut down (7/5) and removed from site.
1979 Annual Totals: P = 520.0 mm; 0 = 40.8 mm;
S = 13.2 Kg/ha
-------
APPENDIX B
Daily Climatic Data
107
-------
TABLE B-l. DAILY MAX IMUM-MININUM TEMPERATURE DATA FOR 1977 WATER YEAR, °C
(values taken from chart to nearest 1/2°C).
Station: Rock Creek Watershed
Day October November December January February March
Max
Min
Max Min
Max
Min
Max
Min
Max
Min
Max
Min
1
-5.5
-16.5
0.0
-3.5
2.0
-2.0
2
-6.5
-12.0
4.0
-5.0
3.0
-3.0
3
-7.5
-12.0
5.0
-5.0
4.0
-2.5
4
-5.5
-17.0
2.0
-4.0
5.5
-3.0
5
-3.0
-14.0
3.0
-8.0
9.0
-3.0
6
1_/
-2.5
-14.0
3.0
-5.0
10.5
-3.0
7
-3.0
-14.5
10.5
-6.0
8.0
1.0
8
4.0
0.0
10.0
-4.0
5.0
0.0
9
0.5
-1.0
7.0
-1.0
3.5
-1.5
10
3.5
-2.0
-3.0
-12.0
11.0
2.5
5.5
-4.0
11
7,0
-3.0
0.0
-6.0
11.0
4.0
6.5
-5.0
12
6.5
-4.0
0.5
-4.5
13.0
4.0
6.5
-3.0
13
6.0
-3.5
0.5
-3.5
9.0
-2.0
1.0
-9.0
14
3.0
-4.0
1.5
-1.0
10.0
-5.0
0.5
-7.0
15
8.0
4.0
1.0
13.0
-2.0
5.5
-5.5
16
7.5
1.0
13.0
3.0
7.5
-1.0
17
13.0
0.0
8.0
1.5 '
9.0
1.0
1.5
-4.5
18
5.5
-5.0
10.0
-1.0
12.5
0.0
3.5
-4.0
19
7.0
-5.5
8.0
-3.5
15.0
1.0
5.0
-4.5
20
6.0
-7.0
8.0
-2.5
17.0
3.0
3.0
-5.0
21
4.5
-4,0
10.5
-4,0
7.5
-1.5
7.0
0.5
22
4.0
-2.5
5.5
-0.5
15.0
-1.5
23
-1.0
-6.0
6.0
-5.0
11.0
1.0
24
0.0
-7.0
5.0
-5.0
17.0
-3.5
25
3.0
-7.0
3.0
-9.0
0.0
-3.0
8.0
-5.0
26
6,5
1.5
3.0
-8.0
3.5
-4.0
6.0
-0.5
27
7.0
-4.0
- 0.5
-7.5
4.0
-2.0
5.5
-3.0
28
7.5
-3.5
1.0
-11.5
6.0
-1.5
4,0
-4.0
29
2.5
-7,0
- 3.5
-7.0
5.0
-4.0
30
-3.0
--8.5
2.0
-10.5
10.0
-4.0
31
-7.0
-11.0
0.0
-5.5
6.0
0.0
(continued)
-------
TABLE B-l (continued)
Apr i 1
May
June
July
Max
Min
Max
Min
Max
Min
1
7.0
-5.0
24.0
9.0
21.0
4.5
2
7.5
-5.0
13.5
5.0
13.5
1.0
3
12.0
-2.0
10.0
3.0
17.5
5.0
4
17.5
-1.5
7.5
0.5
17.5
9.5
5
21.0
2.0
9.5
-3.5
27.0
7.0
6
22.0
2.0
11.0
-3.5
31.0
15.0
7
24.0
5.0
16.0
1.0
26.0
17.5
8
23.0
3.0
15.0
1.5
20.0
7.0
9
8.5
-1.5
22.0
2.0
20.5
3.0
10
11.0
-4.0
12.5
2.5
22.5
6.0
11
11.0
-1.0
12.0
0.0
23.5
10.0
12
15.0
-3.0
16.0
0.5
22.0
9.5
13
9.0
-1.0
16.5
3.5
22.5
7.0
14
9.0
-3.0
10.0
4.5
24.5
7.5
15
13.5
3.0
12.0
0.5
24.0
7.0
16
8.0
-3.0
7.5
-1.0
23.5
7.0
17
7.5
-5.0
6.5
2.5
28.0
6.0
18
7.0
-5.0
8.0
2.0
30.0
11.0
19
7.0
-6.0
14.0
1.5
28.0
11.5
20
11.0
-1.0
16.0
2.5
23.0
12.0
21
13.0
1.0
16.0
4.0
23.5
10.5
22
25.0
4.0
19.0
0.5
24.5
10.0
23
29.0
11.0
15.0
5.5
27.0
7.0
24
30.0
15.0
12.0
1.0
29.0
7.0
25
27.0
7.0
17.0
0.0
26.0
10.0
26
14.0
4.5
11.5
3.0
25.0
11.0
27
18.0
0.0
10.5
0.0
23.0
8.5
28
22.5
2.5
9.5
-1.0
26.0
6.0
29
20.0
7.0
14.5
-2.0
22.0
7.0
30
22.0
4.5
20.0
2.0
27.0
6.5
31
26.5
7.5
August
Max
Min
Max
Min
Max
Min
28.5
9.0
34.5
10.5
21.0
5.0
18.5
6.0
33.0
14.0
22.0
9.0
19.0
6.0
34.5
14.0
23.0
11.5
12.5
1.5
30.5
15.0
23.0
14.0
29.5
11.5
22.5
10.0
30.5
11.0
24.0
8.0
26.0
2.0
31.0
9.5
23.5
8.0
31.0
7.0
31.5
13.0
18.0
6.0
22.0
12.0
31.0
14.0
22.0
2.0
22.5
3.5
30.5
13.5
24.5
6.0
32.5
10.0
23.5
6.0
33.5
11.0
23.0
6.0
34.0
14.0
26.0
5.5
27.5
8.5
32.0
13.5
21.0
8.0
29.0
10.0
32.5
16.0
16.5
5.5
29.5
10.5
34.0
14.0
9.5
3.0
18.5
11.0
35.5
14.0
16.5
2.0
16.0
9.5
35.5
14.5
20.0
10.0
22.5
6.0
34.0
14.0
19.0
6.0
31.0
7.5
35.5
16.0
13.5
6.0
30.0
13.0
28.5
14.0
13.5
6.0
33.0
11.5
25.0
12.0
12.5
-0.5
32.5
13.0
27.0
7.0
10.5
3.5
30.5
14.0
16.0
9.5
10.5
2.5
22.5
12.5
18.0
7.0
11.0
3.0
27.5
11.0
13.0
7.5
13.0
2.0
32.0
12.0
16.0
5.0
13.0
2.0
25.0
12.0
15.0
6.0
12.0
8.0
20.0
8.0
15.0
8.5
10.5
4.5
25.0
5.0
. 16.5
5.0
8.0
5.0
30.0
8.0
19.5
5.0
— Instrument installed in shelter 12/7/77 -
Bendix-Friez Model 594
Hygrothermograph.
-------
TABLE B-2. DAILY MAXIMUM-MINIMUM TEMPERATURE DATA FOR 1978 WATER YEAR, °C
(values taken from chart to nearest 1/2°C),
Station; Rock Creek Watershed
Day
October
November'
December
January
February
March
Max
Min
Max Min
Max Min
Max Min
Max
Min
Max
Min
1
13.5
0.0
11.0
1.0
8.5 - 2.5
-5.0 -21.0
2.0
-4.0
1.5
-11.0
2
14.0
1.0
4.5
-2.5
9.5 7.5
-4.0 -18.0
3.5
0.0
1.0
-9.5
3
12.5
3.5
5.5
-4.0
8.0 0.0
1.0 -10.5
7.0
1.0
0.0
-9.0
4
14.0
5.5
8.0
-4.0
1.0 -4.0
5.0 1.0
10.5
0.0
6.5
-3.5
5
14.0
1.5
7.5
1.5
-2.0 -4.5
6.0 2.0.
11.0
5.0
3.5
-3.0
6
16.0
0.5
6.0
1.5
6.0 -2.5
15.0 -1.5
9.5
2.5
7.0
-1.0
7
11.0
3.0
5.0
-3.5
1.0 -6.0
4.0 -4.0
6.5
3.0
10.5
3.5
8
11.0
3.0
1.0
-6.0
-3.0 -6.0
5.5 1.5
7.5
1.0
8.0
3.5
9
8.0
-2.5
3.5
-3.0
¦ -0.5 -5.0
7.0 1.5
4.0
-2.0
5.5
-1.5
10
10.5
-5.0
10.5
1.5
8.0 -0.5
14.5 -1.0
4.5
-3.0
8.5
-2.5
11
14.5
-2.5
14.0
6.0
8.5 2.0
0.5 -1.5
-0.5
-5.0
5.5
-2.0
12
21.0
1.5
11.0
3.0
7.0 2.5
0.0 -2.5
1.0
-7.0
3,0
-2.0
13
17.0
5.0
10.0
0.0
9.5 2.0
5.0 -2.5
1.5
-5.0
1.0
-1.5
14
18.0
2.0
7.0
-1.0
9.0 4.5
8.0 3.0
3.0
-3.0
2.5
-7.0
15
24.0
4.5
5.5
-0.5
6.0 -1.5
5.0 .5
0.0
-4.0
17.0
-9.5
16
17.0
4.5
3.0
-2.0
12.0 -1.5
5.5 1.5
2.5
-8.5
13.0
-3.0
17
19.0
2.0
-1.5
-10.0
0.0 -2.5
15.0 9.5
2.0
-9.5
18.0
3.0
18
22.0
3.0
-1.5
-10.0
-1.0 -3.0
6.0 1.0
2.0
-2.0
15.0
2.5
19
15.0
2.0
- 2.0 -11.5
3.5 1.0
5.0
0.0
14.0
1.0
20
16.0
1.0
2.0 1.0
11.5
-0.5
15.0
0.0
21
13.0
0.0
0.0 -3.5
7.5 1.0
9.0
-1.0
18.0
1.0
22
17.5
2.0
1.5 -3.5
1.0 -2.5
11.0
-1.0
16.5
5.0
23
15.5
2.0
-1.5 -7.0
-1.0 -6.5
18.0
-1.5
13.0
2.5
24
18.0
1.5
3.0
-3.0
-2.5 -7.5
0.0 -6.5
4.5
-1.0
11.0
3.0
25
9.0
4.0
11.0
0.5
-3.0 -7.5
3.0 -4.5
2.0
-1.5
13.5
3.5
26
9.5
-1.5
6.5
-1.0
-3.5 -13.5
0.0 -2.5
4.0
-1.0
16.0
2.5
27
8.5
-0.5
3.0
-2.0
-3.5 -8.0
4.5 -6.0
1.0
-1.5
15.5
3.0
28
10.0
1.0
6.0
2.0
-1.0 -5.5
2.0 -2.5
1.0
-9.0
18.0
6.5
29
9.5
2.5
8.0
-1.5
1.5 -6.5
8.5 -3.5
23.0
6.0
30
5.5
1.5
1.0
-4.0
-5.0 -11.0
1.0 -10.5
10.5
6.0
31
6.0
0.0
-6.5 -17.5
-2.0 -4.5
16.0
-1.0
(continued)
-------
TABLE B-2 (continued)
Day Apr i1
May
June
July
Max
Min
Max
Min
Max
Min
Max
Min
1
7.5
0.0
13.5
5.0
23.0
3.5
26.0
9.0
2
5.5
0.0
13.0
4.0
25.0
6.0
22.5
6.5
3
10.0
-1.0
6.5
1.5
27.0
9.0
16.5
10.5
4
10.0
1.0
8.0
-1.5
27.0
10.0
11.0
9.0
5
7.5
-0.5
10.5
-1.5
27.5
10.0
18.0
10.0
6
6.0
0.0
15.0
0.0
25.5
11.0
26.0
7.5
7
4.0
0.0
16.5
1.0
23.0
10.5
26.5
11.5
8
9.0
-1.0
19.5
2.5
24.0
8.0
25.0
13.0
9
12.0
-2.0
15.5
3.5
17.0
8.5
26.5
12.5
10
17.5
1.0
13.0
5.0
14.5
6.0
17.5
6.0
11
10.0
0.5
11.0
3.5
18.0
6.0
18.0
4.5
12
9.0
-2.5
12.5
1.5
22.0
12.0
23.5
4.5
13
12.5
-3.5
13.5
6.5
13.0
7.0
27.5
7.5
14
11.5
3.5
13.0
8.0
14.5
3.5
33.0
10.5
15
14.0
4.0
11.0
1.0
15.0
3.0
31.5
12.0
16
9.0
0.0
7.5
1.0
16.5
1.5
10.0
17
9.0
-0.5
12.0
4.5
22.5
3.5
21.0
18
15.0
0.0
18.0
3.0
25.5
2.0
23.0
8.0
19
18.0
2.0
21.5
3.5
19.0
1.0
25.0
7.0
20
6.5
1.0
22.0
7.5
25.0
3.5
26.0
7.5
21
8.5
0.0
21.5
5.0
25.0
6.0
29.0
9.5
22
9.0
-0.5
11.0
1.0
23.0
6.0
31.0
10.5
23
9.0
0.0
10.5
1.5
22.5
10.0
34.0
12.5
24
17.0
4.5
11.0
3.0
13.5
7.5
31.0
14.0
25
21.5
11.0
12.0
-1.5
17.0
6.0
33.0
10.0
26
15.0
8.0
16.0
-1.5
22.0
3.0
31.0
13.0
27
6.0
5.0
13.5
6.5
26.0
6.5
27.5
11.0
28
9.5
2.0
13.5
7.5
30.5
10.5
29.0
7.0
29
11.0
1.0
11.5
3.0
24.5
9.5
31.0
9.0
30
15.0
-0.5
14.0
-2.0
22.0
10.0
31.5
9.5
31
18.0
3.0
30.5
10.5
August
Max
Min
September
Max Mm
31.0
30.5
31:5
35.0
30.5
31.0
32.0
34.0
34.0
29.0
10.5
11.5
14.0
11.0
12.5
9.5
11.0
11.0
12.0
9.5
24.0
27.0
29.5
25.0
20.5
14.5
12.0
16.5
22.0
15.0
14.0
12.0
7.0
9.0
10.0
6.0
10.5
11.0
5.5
5.5
10.0
5.0
5.0
3.0
20.0
15.0
10.0
15.0
6.0
16.0
7.0
21.0
3.5
17.0
10.5
13.0
8.5
20.0
7.5
12.0
3.0
12.0
6.5
15.0
5.0
20.0
5.0
20.0
3.0
22.0
9.0
27.0
7.0
16.0
6.0
28.0
6.5
20.0
3.5
29.5
10.5
21.5
4.0
22.5
5.0
25.0
5.5
15.5
4.0
27.0
7.5
20.0
2.5
19.0
10.0
20.0
7.5
18.0
9.0
-------
TABLE (3-3. DAILY MAXIMUM-MINIMUM TEMPERATURE DATA FOR 1979 WATER YEAR, °C
(values taken from chart to nearest 1/2°C).
Station: Rock Creek Watershed
Day
October
November
December
January
February
March
Max
Min
Max Min
Max
Min
Max Min
Max
Min
Max
Min
1
14.5
1.5
13.0 -10.0
-0.5
-3.0
-11.5
-26.0
2.0
-6.0
2
17.5
-1.0
13.0 -4.0
0.5
-9.0
-6.0
-24.0
2.5
-4.5
3
18.0
-0.5
11.0 3.5
4.5
-4.0
-4.0
-10.5
6.0
-5.0
4
17.5
0.5
11.0 -5.0
4.5
-11.0
2.0
-6.0
6.5
1.0
5
20.0
-1.5
4.0 -9.0
-3.5
-9.5
4.5
-3.0
7.5
4.0
6
22.0
0.0
10.0 -7.0
-3.5
-15.0
4.5
-3.0
11.5
5.0
7
17.0
2.5
13.5 3.0
-5.5
-21.0
2.5
-8.5
10.0
-1.0
8
21.0
2.0
12.0 -4.0
-7.5
-16.0
5.5
-7.5
6.5
-4.0
9
22.0
4.0
2.5 -9.5
¦ -2.0
-7.5
5.0
3.0
9.0
-5.5
10
14.0
8.0
-4.0 -11.0
1.0
-6.0
6.0
2.0
13.5
-2.5
11
13.5
4.0
-2.0 -12.0
4.0
-3.0
-2.0 -4.0
6.5
2.0
16.0
-2.0
12
13.0
-4.0
-3.0 -9.0
1.0
1.0 -8.0
8.5
1.0
10.0
-2.0
13
16.5
-5.0
0.0 -12.0
-8.5
8.0
2.0
14.0
-4.5
14
21.0
-2.0
3.0 -14.0
3.0
-4.0
-4.0 -9.0
2.0
-3.0
16.5
-1.0
15
20.0
2.0
3.0 -1.0
-0.5
-5.0
3.5
-4.0
16.0
0.5
16
17.5
2.0
4.5 -0.5
-0.5
-6.5
3.5
-2.0
4.5
0.5
17
18.0
1.5
4.0 -0.5
2.0
-1.5
4.5
-2.0
7.0
-4.0
18
20.0
1.0
1.5 -2.5
-1.0
-5.5
-5.5 -17.0
3.5
-1.0
11.0
-5.0
19
22.0
1.0
-2.5 -10.0
-4.5
-8.0
-1.5 -15.0
2.0
-4.5
12.5
-1.5
20
15.0
5.0
-6.0 -9.5
2.5
8.0
5.0 -2,0
2.5
-7.0
10.0
-2.0
21
10.0
-2.0
-2.5 -9.0
2.5
0.0
3.0 -12.0
0.0
-3.0
11.0
-3.0
22
12.0
-7.0
-4.5 -8.5
3.0
-4.0
-3.5 -6.5
2.0
-4.0
13.0
-2.0
23
15.5
-2.0
0.0 -6.0
5.0
-6.0
-1.5 -15.5
1.5
-4.0
14.0
-2.5
24
14.0
-5.0
0.0 -2.0
4.0
-8.0
-3.0 -15.0
5.0
-3.0
14.5
1.0
25
11.0
-7.0
-1.0 -4.0
-0.5
-12.5
-8.0 -15.0
5.5
2.5
8.5
1.5
26
15.5
-5.0
-1.5 -4.5
0.0
-12.5
-3.5 -11.0
6.0
1.5
7.0
1.5
27
9.5
-1.5
-0.5 -8.0
-2.0
-13.0
-4.5 -9.0
1.5
-3.0
6.0
0.0
28
14.0
-4.0
1.5 -3.5
-11.5
-20.0
-8.0 -15.0
2.5
-5.0
3.0
-1.0
29
4.0
-6.0
2.0 -1.5
-16.0
-25.0
-8.5 -21.0
4.5
-1.0
30
7.0
-7.0
2.0 -1.0
-14.0
-29.0
-8.0 -22.0
4.0
-1.0
31
10.0
-9.0
-7.5 -20.0
2.5
-2.0
(continued)
-------
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
TABLE B-3 (continued)
April May June ~ July
Max Min
Max
Min
Max
Min
Max
Min
3.0
-5.0
23.0
5.0
6.0
-5.0
26.0
7.5
4.0
-4.5
19.5
1.5
25.5
10.5
10.0
1.0
14.5
7.5
21.5
10.0
14.5
0.0
9.0
3.5
18.0
7.0
8.5
2.0
10.0
-0.5
11.0
0.0
9.0
-0.5
9.0
-2.5
15.0
-0.5
13.0
3.0
10.5
2.5
19.5
0.0
5.5
-1.0
12.5
1.0
24.0
4.0
5.0
-2.5
11.0
1.5
26.0
7.5
2.0
-1.0
15.0
1.0
29.5
10.5
7.5
-2.5
16.0
1.0
25.5
1.0
7.0
0.0
16.5
5.0
16.0
1.5
8.0
-0.5
21.0
3.0
16.5
0.0
9.0
0.0
22.0
6.0
18.5
1.0
15.5
3.5
16.0
4.0
15.0
5.0
7.0
-2.0
16.0
2.5
8.0
5.5
6.0
-4.0
16.0
4.0
16.0
7.0
5.0
-4.0
17.0
'-0.5
15.5
5.5
9.5
-5.0
20.5
1.0
18.0
3.0
13.0
-4.0
21.5
6.5
19.5
3.5
11.5
4.5
26.5
6.0
20.5
4.0
8.5
3.5
17.0
11.0
23.0
4.0
10.0
2.0
19.0
7.5
26.0
5.5
13.5
2.0
23.5
5.0
29.0
8.5
23.5
9.0
30.5
11.0
12.0
3.0
26.5
10.0
17.0
9.0
-1.5
31.5
12.0
15.0
4.5
13.0
-2.0
26.0
10.0
m
m
17.0
20.0
-2.0
4.0
16.0
7.0
10.0 4.5
16.0 2.5
27.5 1.5
27.5 11.01/
collection terminated.
-------
TABLE B-4. ROCK CREEK WATERSHED DAILY PAN EVAPORATION DATA
FOR 1977 IN MILLIMETERS!./
Day Jan
Feb Mar Apr
May
Jun
Jul
Aug
Sep
Oct
Nov Dec
1
*21
3.6
15.4
~
~
0.1
2
k
4.3
~
31.0
9.5
~
-0.3
3
15.4
3.2
~
8.5
2.1
2.2
1 .5
4
2.8
2.6
~
*
3.5
~
0.3
5
2.4
1.6
k
19.0
3.1
5.5
0.9
6
2.7
~
25.7
~
*
0.7
*
7
~
11.8
4.8
k
15.8
•k
1 .9
8
5.2
3.2
7.7
24.7
~
~
1.7
9
3.2
*
*
11.4
11.1
-0.3
10
2.4
k
~
10.5
~
4.0
0.4
11
2.2
k
~
8.1
~
1 .7
12
k
k
•k
9.4
14.9
4.2
*
13
5.9
23.2
37.2
~
~
~
5.0
14
4.9
4.5
6.4
~
9.0
4.5
-0.2
15
*
4.5
8.2
29.9
*
*
-0.3
16
5.5
~
*
k
8.1
~
0.82/
17
-0.1
k
lfi.3
18.8
1.0
8.7
18
0.9
k
2.7
9.5
10.7
1 .8
19
0.0
k
1 .8
¦*
3.5
*
~
20
3.2
k
8.2
k
0.8
~
21
4.2
38.5
6.7
k
2.5
fi.5
22
5.8
8.4
33.5
1.2
0.9
23
9.7
7.2
~
*
1.2
~
24
1.7
10.6
~
13.4
0.6
6.1
25
2.5
~
20.3
•k
0.8
2.1
26
4.0
15.^
~
5.7
•k
0.3
27
- 2.7
9.4
5.2
~
¦k
28
£/
2.7
17.6
16.4
2.8
2.5
1.6
29
1 .5
6.3
*
1.4
0.7
~
30
~
9.2
*
*
1.6
7.2
1 .9
31
~
*
2.6
0.6
1/Evaporation pan is a standard 4 foot diameter monel pan.
2/* indicates days accumulated.
U Pan removed 11/16.
£/Pan initially filled 4/29.
114
-------
TABLE B-5. ROCK CREEK WATERSHED DAILY PAN EVAPORATION DATA
FOR 1978 IN MILLIMETERS!/
Day Jan
Feb Mar Apr
May
Jun
Jul
Aug
Sep
Oct
Nov Dec
1
2.0
9.1
10.3
~
29.2
~
~
1.5
2
~
2.9
~
•k
7.6
6.2
9.8
1.3
3
1.6
4.4
~
15.9
~
~
~
0.3
4
~
*
~
~
16.9
~
4.7
~
5
2.1
4.7
~
-1.2
~
*
~
~
6
~
*
~
2.0
~
17.8
6.3
3.5
7
-0.6
*
33.4
4.6
~
0.8
~
0.9
8
2.4
10.3
3.4
~
~
1.0
~
3.8
9
*
*
6.2
*
40.2
*
~
2/1 .9
10
6.3
6.9
~
~
9.7
6.4
~
11
6.6
~
~
20.6
10.1
2.6
15.1
12
2.4
8.0
14.8
3.3
~
1.6
~
13
3.3
2.0
2.0
5.6
~
0.9
4.6
14
~
•k
0.8
7.0
6.7
~
~
15
7.6
1.5
3.9
7.0
*
3.2
~
16
-3.3
1.9
2.6
•k
4.9
~
8.2
17
3.2
-0.2
3.0
10.0
~
*
~
18
*
~
~
4.0
~
6.6
3.5
19
7.9
6.4
13.2
4.8
9.5
2.1
~
20
3.0
*
5.0
7.0
2.4
1 .7
5.3
21
2.2
~
4.2
7.9
-0.1
~
~
22
~
15.0
7.5
8.3
2.4
2.9
~
23
— 7.8
*
5.3
*
0.7
~
6.4
24
~
6.7
3.8
~
2.7
~
2.6
25
7.1
~
~
23.2
3.3
8.3
2.6
26
2.3
5.8
3.5
9.3
1 .7
~
~
27
-1.2
*
5.2
7.1
~
9.8
3.9
28
0.4
~
6.7
5.4
7.1
~
~
29
~
~
7.6
~
5.2
5.0
~
30
~
12.9
~
~
5.1
*
3.5
31
U
4.0
~
0.3
0.3
1/Evaporation pan is a standard 4 foot diameter monel pan. Readings
taken at irregular times of day and days.
£/Pan initially filled 3/31.
2/Pan removed 11/9.
115
-------
TABLE B-6. ROCK CREEK WATERSHED DAILY PAN EVAPORATION DATA
FOR 1979 IN MILLIMETERS!/
Day Oct Nov
Dec Jan Feb Mar Apr
May
Jun
Jul Aug Sep
1
2.5
5.2
~
2
2.7
~
12.0
3
~
~
~
4
6.2
21.4
•k
5
0.9
~
17.4
6
1.5
13.5
If
7
2.8
~
8
1.9
7.3
9
1.8
~
10
*
~
11
5.5
17.6
12
*
~
13
~
17.4
14
13.9
~
15
6.6
10.7
16-
4.2
~
17
1/
*
18
2.9
11.0
8.1
19
2.0
~
*
20
1.4
*
4.2
21
*
16.4
22
~
~
10 .6
23
7.7
13.3
*
24
0.2
1.5
*
25
1.1
3.0
18.8
26
~
~
~
Z7
7.5
13.3
28.
~
~
~
29
~
22.1
16.1
30
15.4
3.4
~
31
4.8
1/Evaporation pan is a standard 4 foot diameter monel pan. Readings
taken at irregular times of day and days.
1/Pan initially filled 4/17.
1/Pan removed and station closed 7/5/79.
116
-------
TABLE B-7. ROCK CREEK WATERSHED DAILY WIND RUN DATA
FOR 1977 IN KILOMETERS!/
Day Oct Nov
Dec Jan Feb Mar Apr
May
Jun
Jul
Aug
Sep
1
~
116
73
~
~
2
~
87
ir
205
100
3
336
29
~
53
32
4
255
41
~
46
5
141
33
~
155
39
6
64
~
223
•k
~
7
~
88
21
~
89
8
137
74
33
18^
~
9
68
~
*
83
170
10
46
~
~
81
~
11
131
~
~
62
~
12
*
~
ir
54
146
13
116
193
252
~
~
14
107
39
55
~
83
15
~
28
39
195 "
*
16
185
~
~
158
17
72
~
117
110
24
18
41
*
83
52
105
19
68
*
32
~
80
20
64
~
67
*
19
21
114
263
36
~
93
22
~
54
~
242
29
23
*li
172
32
~
~
55
24
~
73
49
~
134
79
25
353
31
~
183
~
79
26
68
68
97
~
133
~
27
166
125
~
75
69
~
28
76
118
110
175
60
103
29
76
58
49
~
116
50
30
~
80
~
~
50
48
31
~
~
70
LI Anemometer is Science Associate Model 404 which is 3 cup N.W.S. Spec
unit with contacting and counter totalizing. Readings taken at irregular
times of day and correspond to evaporation readings. Anemometer height
15 cm above rim of pan, about 30 cm above soil.
I/* indicates days accumulated.
117
-------
TABLE B-S. ROCK CREEK WATERSHED DAILY WIND RUN DATA
FOR 1978 IN KILOMETERS!/
Day
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
1
~
159
53
~
47
84
81
194
~
*
99
*
2
~
213
291
~
~
~
k
58
110
~
29
45
3
126
135
380
172
402
178
280
164
*
103
:k
k
4
~
22
208
125
109
~
*
~
~
*
107
~
5
105
87
~
191
~
107
183
201
~
31
~
~
6
~
~
257
337
247
k
~
¦k
~
14
~
98
7
138
191
254
100
148
158
133
~
224
20
k
8
8
~
116
105
124
166
107
70
204
13
~
~
61
9
~
82
~
73
139
34
~
~
83
•k
145
~
10
217
96
60
42
62
*
190
222
~
k
39
99
11 *
96
182
40
~
k
238
k
*k
122
62
34
12
87
*
282
~
~
181
83
343
254
28
~
60
13
~
306
177
60
257
~
67
63
16
28
k
34
14
71
163
179
*
*
320
~
k
6
20
48
~
15
~
92
*
~
114
54
131
83
37
24
~
48
16
~
182
448
403
33
k
196
110
28
*
60
~
17
201
~
~
~
~
112
184
62
19
100
~
18
36
162
248
129
~
~
*
~
*
29
•k
142
19
~
~
~
~
73
~
220
81
60
18
107
27
20
*
k
186
123
~
299
88
k
19
31
18
21
21
178
308
109
*
64
71
178
k
4
51
1
~
22
33
*
~
~
35
32
*
168
47
48
22
70
23
*
100
68
359
~
~
332
~
31
*
24
*
24
216
~
~
*
117
247
*
133
18
*
11
~
25
149
238
k
38
46
k
206
*
~
72
17
86
26
75
316
~
*¦
•k
~
57
116
80
28
10
~
27
~
67
172
86
'64
171
95
*
15
44
~
76
28
97
188
77
-k
:k¦
*
~
*
26
11
39
*
29
*
189
*
•k
91
147
~
37
~
28
70
30
261
101
133
41
~
*
335
*
k
21
~
31
166
*
~
177
53
•k
3
1/See 1977 notes.
.118
-------
TABLE B-9. ROCK CREEK WATERSHED DAILY WIND RUN DATA
FOR 1979 IN KILOMETERS!/
Day Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep
1
*
16
41
*
~
~
~
61
26
k
2
166
14
k
184
25
57
402
59
~
268
3
~
8
~
43
~
~
76
~
k
~
4
49
~
323
*
~
198
229
114
170
~
5
~
~
84
76
96
64
~
45
k
60
6
58
140
20
*
106
51
229
222
315
1/
7
~
14
~
135
294
93
186
62
~
8
k
194
4
~
~
*
k
66
116
9
k
65
*
*
203
186
218
76
~
10
k
~
~
135
135
k
k
k
~
11
301
~
370
*
175
k
276
165
87
12
~
k
293
78
85
205
k
k
~
13
77
230
118
~
291
79
269
k
159
14
~
22
~
~
121
57
k
226
~
15
*
46
453
307
99
~
k
57
93
16
82
k
~
*
141
125
342
96
k
17
~
99
~
80
159
97
111
~
k
18
37
44
383
13
223
~
110
251
80
19
~
k
~
20
~
55
107
~
k
20
92
165
159
~
139
k
71
~
103
21
•k
~
~
~
88
103
~
202
*
22
k
45
587
126
~
~
~
k
68
23
136
~
~
*
120
116
162
122
k
24
83
6
520
38
~
*
37
42
k
25
37
~
*
*
~
~
28
34
78
26
~
~
93
5
404
402
k
~
~
27
49
39
36
~
116
70
94
~
49
28
k
79
~
*
87
68
k
k
k
29
k
43
166
20
164
k
365
61
30
146
128
~
*
223
190
48
~
31
13
~
25
~
59
1/See 1977 notes.
ZJUnit removed and station shut down 7/5/79.
119
-------
APPENDIX C
Sample arid Analytical Procedures
120
i
-------
TABLE C-l. EPA-ARS GRAZING PROJECT, LABORATORY ANALYSES
Parameter
Samples on which
analysis is
performed
Preliminary
treatment
Preservation
Storage
Per iod
Method
Reference
Total
All except
None
Sample kept cool
0-24 hrs
Membrane filter,
Standard Methods, 14th
col iforms
precipitation
as possible before
M-coliform broth,
Edition
it reached lab
MF enao medium
Fecal
All except
None
Sample kept cool
0-24 hrs
Membrane filter,
Standards Methods, 14th
coli forms
precipitation
as possible before
FC broth
Edition
it reached lab
Fecal
All except
None
Sample kept cool
0-24 hrs
Membrane filter,
Standard Methods, 14th
streptococci
precipitation
as possible before
FC streptococcal
Edition
it reached lab
broth
Nitrate-
All
Sample filtered
Refrigeration at
0-12 wks
Auto Analyzer II
EPA Manual of Methods
Nitri te
as soon as pos-
4°C
Automated Cad-
for Chemical Analysis
sible (within 24
mium Reduction
of Water and Wastes,
hrs) through a
Method
and Technicon Auto
0.45 um membrane
Analyzer 11 Method No.
100-70W
filter
Ni tr i te
A few samples
Sample filtered
Refrigeration at
0-72 hrs
Colorimetric
EPA Manual
per event were
soon as possible
4"C
diazotization
checked qual na-
(within 24 hrs)
tively and if
through a 0.45
positive were
iim membrane
analyzed quanti-
fiIter
tatively
Amnion i a,
All
None required,but
Refrigeration at
0-12 wks
Auto Analyzer II
EPA Manual and V.L.
dissolved
since the same
4°C
Automated Colori-
Cochran, ARS Pullman, WA
sample portion was
metric Phenate
used for nitrate
Method, modified
analysis, the
set up for Dual
sample was f i 1 tered
NO3 and IIH.3
through a 0.45 pin
analysis
membrane filter
-------
ro
ro
Parameter
Samples on which
analysis is
performed
Total (Kjeldahl) Number 0)
nitrogen sufficient to
characterize an
event (based on
hydrograph and
NO3 + NHj
results)
Total
(Kjeldahl)
nitrogen,
dissolved
Dissolved
organic
nitrogen
(calculated)
Preliminary
treatroenL
None
Number (2) suf-
ficient to cover
range of sample
values (based
on soluble
NO3 + NH|
results
Same samples as
dissolved TKN
Filtered imme-
diately through
0.45 urn membrane
filter (same
sample portion
used for
soluble NOj +
NH4 analysis
N/A
Dissolved
phosphorus
(Orthophos-
phate)
All
Filtered imme-
diately (within
24 hrs of collec-
tion) through a
0.45 um membrane
f i1ter
Total Number suffi- None
phosphorus cient to charac-
terize an event
(based on hydro-
graph and ortho-
PO^ results (1)
TABLE C-l. (continued)
Preservat ion
Storage
Per iod
Method
Reference
Refrigeration at
4 C
0-12 wks be- Technicon BD-40 Technicon Auto Analyzer
fore digestion Block H2SO4 II Industrial Method
then another digestion, No. 376-75 W/B, and
0-12 weeks be- assayed using the Technicon. Auto Analyzer
fore analysis Auto Analyzer II II Industrial Method
Colorimetric No. 329-74 W/A
Phenate Method
Refrigeration at
4 C
3-12 wks
before diges-
tion, then
another 0-12
wks before
ana lysis
Technicon BD-40
Block H2SO4
digestion,
assayed using
the Auto Analy-
zer II Colori-
metric Phenate
method
Technicon Auto Analyzer
II Industrial Method No.
376-75 W/B, Technicon Auto
Analyzer II Industrial
Method No. 329-74 W/A
N/A
Frozen
N/A
0-8 wks
Soluble org. N
calculated. Dis-
solved org. N =
TKN dissolved -
(dissolved NH3 +
NO3 + NOj-N)
Colorimetric
phosphomolybdate
ascorbic acid
single solution
reagent
N/A
EPA manual
Refrigeration 0-12 wks Technicon BD-40 Technicon Auto Analyzer
at 4 C before diges- Block H2SO4 II Industrial Method
tion, then Digestion Assayed No. 376-75 W/B, Technicon
another 0-12 using the Auto Auto Analyzer II Industrial
wks before Analyzer II Auto- Method No. 329-74 W/A
analysis mated Colorimetric
Ascorbic Acid
Reduction method
-------
TABLE C-l. (continued)
Samples on which
analysis is
Preliminary
Storage
Parameter
performed
treatment
Preservation
Period
Method
Reference
Total
dissolved
phosphorus
Dissolved
organic
phosphorus
(calculated)
Total
organic
phosphorus
Total
organic
carbon
Chemical
oxygen
demand
Number suffi-
cient (1) (10-20
percent) to cover
the range of
values based on
total P and
ortho-PO^
results
Minimum number (3)
of samples (.5 per-
cent needed to
determine relative
percentage of organ-
ic P to total P
All except
precipitation
A11 except
precipitation
Refrigeration
at 4"C
Filtered imme-
diately (within
24 hrs of collec-
tion through a
0.45 pm membrane
filter (same
sample portion as
used for ortho-
P04
Filtered immediately Frozen
through a 0.45 pm
membrane filter.
Same sample portion
as used for ortlio-
P0-3
None
Refrigeration
at 4"C
None
None
Refrigeration
at 4"C
H2SO4 t0 PH<2
Refrigeratio
at 4"C
0-12 wks be-
fore diges-
tion, then
another 0-12
wks before
analysis
0-12 wks
0-12 wks
BD-40 Block H2SO4
digestion.assayed
using the Auto
Analyzer II Auto-
mated Colori-
metric Ascorbic
Acid Reduction
method
Technicon Auto
Analyzer II Industrial
Method No. 376-75 k/B
Technicon Auto
Analyzer Industrial
Method No. 329-74 W/A
Dissolved hydrolyz- EPA Manual
able phosphoric
determined by H2SO4
hydrolysis. Dissolved
org. P calculated.
P.D. Org. = P-D total
- (P-D hydro + P-D
ortho)
Total Hydrolyzable EPA Manual
Phosphorus determined
by H9SO4 Hydrolysis
Total Org. P calcu-
lated P, Org = P,
Total - (P, hydro +
P ortho)
0-6 months Combustion infrared
0-12 wks Normal-low level
combination adapted
to our COD range
( = 10-150 mg/1)
Analysis of TOC per-
formed by Dr. A1
Lingg, Univ. of Idaho,
Dept. of Bacteriology
and Biochemistry
Standard Methods,
14th Edition
-------
Parameter
Biochemical
oxygen
demand
Samples on which
analysis is
performeo
Preliminary
treatment
A11 except precipi-
tation and wel1
samples. Some
samples also had a
rate BOD analysis
None
Sediment All None
(suspended
sol ids)
Solids Samples with high N/A
dissolved sediment concentra-
(calculated) tion analyzed by the
evaporation method
pH All None
Specific All None
conductance
Chloride All Sample filtered
(dissolved) as soon as possib
through 0.45 urn
membrane filter
TABLE C-l. (continued)
Preservat ion
Storage
Period
Method
Reference
Sample kept cool 0-24 hrs
as possible be-
fore it reached
lab
None
Standard 5 days,
20"C (dissolved
oxygen determined
with a membrane
electrode meter),
Manometric BOC
2-12 wks Filtration except
for high sediment
samples were
analyzed by the
evaporation method
Standard Methods,
14th Edition; Yellow
Spring Inst. C 00
Meier Instruction;
HACH Chemical Mano-
metr ic BOD Apparatus
Instruction Manual
USGS Techniques of
Water Resources
Investigations, Book
5, Chap. CI, Lab.
Theory and Method for
Sediment Analysis
N/A
2-12 wks
Calculation
Same as auove
Sample kept cold 0-24 hrs
as possible be-
fore it reached
the lab for analy-
sis
Meter
Standard Methods,
14th Edition
Sample kept cold 0-24 hrs
as possible be-
fore it reached
the lab for analy-
sis
Meter
Standard Methods,
14th Edition
Refr igerat ion
at < C
0-6 months
Coulometr ic-
amperometric fil-
trat ion wi th s ilver
ions
Buchler-Cutlove
Chloridometer
Instruction for
Operation Manual
-------
TABLE C-l. (continued)
Samples on which
analysis is
Preliminary
Storage
Parameter
performed
treatment
Preservation
Per iod
Method
Reference
Sodium and
Number sufficient
Sample filtered
HNO3 to pH<2
6-12 months
Flame photometry
Standard Methods,
potassium
(10-20 percent) to
through 0.45 pm
Refrigeration
14th Edition
(d i ssolved)
characterize the
membrane filter
at 4"C
range of values
based on pH, SC, and
CI" results
Calcium and
Number sufficient
Sample filtered
HNO3 to pH<2
6-12 months
Atomic absorption
EPA Manual
magnesium
(10-20 percent) to
through 0.45 pm
Refrigeration
(dissolved)
characterize the
membrane filter
at 4"C
range of values
based on pH, SC, and
CI" results
Dissolved
oxygen
Sediinent(S)
phosphorus
(calculated)
Performed periodi-
cally at study
streams
N/A
N/A
N/A
Number(6) suffi-
cient (10-20 per-
cent to cover the
range of values
based on total P and
ortho-PO^ results
Exchangeable^) Minimum^)
sediment
amnion i a
(calculated)
Sediment
ni trogen
(calculated)
N/A, see (4)
None
ber (<5 percent) of
samples needed to
determine range of
values (samples were
be chosen on basis
of total sol ids)
Maximum number of
samples needed to
determine range of
values (based on TKN
and exchangeable
sediment NH3-N
results)
N/A
N/A, see (4) N/A, see (4)
Refrigeration
at 4"C
0-6 months
N/A
N/A
Membrane electrode
meter
Yellow Springs Inst.
Co. Model 54 ARC Co.
Meter Instruction
Manual
Sediment phosphorus
found by calculation,
sediment P = total P -
total dissolved P.
See (3)
Extraction with 2N
KC1 assayed using
Auto Analyzer II
Automated Colori-
metric Phenate Method
Actual sediment NH3-N
found by calculation.
See (7)
Sediment N found by
calculation,
sediment N = TKN +
exchangeable sediment
NH3-N - (dissolved
NH3+NO2 + NO3-N)
or Total N - Tote)
Soluble N
Black, C. A. (Ed.)
Methods of Soil
Analysis
-------
TABLE C-l. (continued)
Samples on which
analysis is Preliminary Storage
Parameter performed treatment Preservation Period Method Reference
Soil
6-in increments to
None
None
None, analysis
Direct
Black, C. A. (Ed.)
moisture
72 in (or to bed-
begun immed-
Methods of Soil
rock) soil cores at
diately
Analysis
9 sites throughout
the watershed
Soil
Same as above
Air dried and
Stored in cool.
0-15 months
2N KC1 extraction
Black, C. A. (Ed.)
n i trate
ground to pass
dry area
steam distillation
Methods of Soil
80-mesh screen
Analysis
Soi 1
Same as above
Same as above
Same as above
0-15 months
2N KC1 extraction
Black, C. A. (Ed.)
ammon ia
steam disti1 lation.
Methods of Soi1
Some samples assayed
Analysis
using Technicon
Auto Analyzer I I
So i1 pH
Same as above
None
None
None
1:1 water so i1
Same as above
paste
Soil
6-in increments to
Air dried and ground
Stored in cool,
15 months
NaC203H3 extraction,
Performed by
phosphorus
36-in, and 12-in
to pass 80-mesh
dry area
Colorimetric deter-
Wash. State Univ.
(available)
for the 2d 36 inches
screen
minat ion
Soil Testing Lab.
to 72-in increments
(or to bedrock) of
soi 1 cores at 9 s ites
throughout the
watershed
Uiost of the first water year's (J977) samples were depleted in determining the best procedures for other parameters. In addition,
problems in developing workable TKN and Total P procedures led to only a small percentage ( 15 percent) of samples analyzed for
these two parameters for the 1977 water year.
-No dissolved TKN or dissolved organic nitrogen analyses were done on 1977 water-year samples.
^No total organic phosphorus or dissolved organic phosphorus analyses were done on 1977 water-year samples.
4B0D test results were not reported to EPA due to uncertainty over the usefulness of the BOD. We were performing a standard BOO
test in conjunction with a rate BOD test as a concurrent experiment.
-------
^Sediment phosphorus (P.S.) was determined by the difference between total phosphorus (P) and total dissolved phosphorus (P—0) due
to the low sediment amounts and the colloidal nature of the sediment present in the runoff. Sediment phosphorus (P-S) = total
phosphorus (P) - total dissolved phosphorus (P-D).
&No sediment phosphorus and exchangeable sediment ammonia values were available for the 1977 water year. Attempting to concentrate
enough sediment for analysis while obtaining a representative sample were not.feasible given the low sediment^amounts and the
colloidal nature. Therefore, sediment phosphorus was found by the calculations in (6) and sediment ammonia by the calculation in
(7).
^Due to the low amounts of sediment present in these samples, the total runoff sample (water + sediment) was extracted for ammonia.
Exchangeable sediment ammonia values were found by calculation. Exchangeable sediment NH3-N = exchangeable runoff (water +
sediment) N - dissolved NH3-N.
-------
Totol Sompl
Total Sample (no filtration)
frozen immedi-
ately
immediately Refrigeration
ately
pH < 2
Refrigeration
Filtered immediately
through a 0.45 fim membrane filter
Not enough residue in runoff
samples for direct sediment
analysis.
Refrigeration Refrigeration
frozen
HN03 to pH< 2
Refrigeration
EC
BOD
COD
TOC
Filtrate
Residue
Dissolved
cr
Sediment
(total
solids)
Specific
Conductance
Bacterial
Analyses
Dissolved
NA+ K~
+2
Dissolved
Ortho-PO^3,
Hydrolyzable
P and
Total P
TKN,
Total P,
Exchangable
Runoff NH3 -N,
Hydrolyzable
SAMPLE
(1000 ml)
Univ. of Idaho
Ag. Eng. Lab.
SAMPLE
(1000 ml)
ARS Water
Quality Lab
Figure C-l. ANALYTICAL SCHEME OF ARS-EPA GRAZING PROJECT
WATER QUALITY SAMPLE MANAGEMENT
-------
APPENDIX D
Watershed Quality Data
129
-------
TABLE D-l. OXYGEN DEMAND, PH, SC, CL, AND CATION DELIVERY BY RUNOFF FROM THE
ROCK CREEK MAIN WATERSHED FOR WATER YEAR 1977
Event dates
Water
delivery
TOC
COD
BOD
PH
SC
CI
Na
K
Ca
Mg
m3
—Average mg/1-
pmhos/ —
—Average mg/1—
1976
Dec. 26-27
158.3
14.8
73
3.6
7.1
135
4.2
6.8
5.8
9.4
3.0
1977
Jan. 16-19
1,795.8
22.2
111
6.1
7.2
60
2.8
3.8
5.5
7.6
2.2
Feb. 8-11
105.0
32.2
87
8.3
7.2
195
6.8
7.6
8.5
16.8
4.8
Feb. 28-Mar. 1
24.9
14.7.
37
4.0
8.2
245
7.4
17.7
5.0
23.0
6.0
Mar. 7-10
65.5
16.1
38
2.6
8.1
279
7.2
21.7
5.2
24.6
5.5
Mar. 15-20
52.1
13.9
22
2.1
8.0
265
5.9
18.0
4.8
23.2
5.8
Mar. 27-28
15.7
15.8
31
2.4
8.0
265
5.8
18.0
4.6
21.3
5.0
Apr. 13-14
4.9
29.3
79
5.8
7.9
332
8.4
25.7
6.2
27.2
5.7
May 2-4
3.6
26.0
56
5.9
8.0
307
3.8
25.7
5.2
26.4
8.2
May 17-18
11.8
14.9
39
3.0
7.9
274
1.5
24.1
4.3
31.4
8.5
May 26-27
3.7
20.5
48
3.4
8.3
286
0.9
18.3
4.1
35.1
8.3
June 4
0.2
25.7
68
-
7.8
382
2.7
30.0
18.0
41.2
8.8
kg/ha
Total delivery 2241.5 2.2 10 0.6 0.4 0.6 0.6 1.1 0.3
-------
TABLE D-2. OXYGEN DEMAND, PH, SC, CL, AND CATION DELIVERY BY RUNOFF FROM THE
ROCK CREEK CHECK WATERSHED FOR WATER YEAR 1977
Water
Event dates
delivery TOC COD BOD pH
SC CI
Na
K
Ca Mg
m3 —Average mg/1- pmhos/ Average mg/1
cm
1976
EecT 26-27 82.9 12.3 76 4.0 7.4 43 1.8 0.7 2.8 2.0 0.6
1977
Jan. 16-19
206.9
13.2
50
6.2
7.0
31
1.5
0.8
3.2
4.4
1.0
Feb. 8-10
12.2
33.1
94
7.9
7.1
58
2.4
1.0
5.6
7.2
1.6
Mar. 8-9
2.6
15.9
45
1.7
7.8
30
0.6
1.8
1.7
2.3
0.9
Mar. 19
< 1.0
21.1
37
2.8
7.6
30
0.6
1.6
2.2
2.3
0.8
Mar. 27
< 1.0
15.0
15
3.0
6.9
34
0.9
3.4
1.3
3.6
1.0
kg/ha
Total delivery 305.0 4.7 19.9 1.9 0.5 0.3 1.1 1.3 0.3
-------
TABLE D-3. OXYGEN DEMAND, PH? SC, CL, AND CATION DELIVERY BY RUNOFF FROM THE
ROCK CREEK MAIN WATERSHED FOR WATER YEAR 1978
Event dates
Water
delivery
TOC
COD
BOD
pH
SC
CI
Na
K
Ca
Mg
Event type
—Average mg/1-
pmhos/
rm
—Average mg/1
1977
Ull
Oct. 30-Nov. 2
15.6
25.7
59
4.0
7.7
288
12.4
25.4
11.0
16.6
6.5
Rain
Nov. 8
22.9
70.5
701
5.6
7.9
300
15.6
35.5
11.1
22.0
8.6
Pond draining
Nov. 13-16
26.0
17.2
40
2.8
8.1
228
8.5
25.3
6.6
14.6
5.4
Rain
Nov. 25-30
304.5
9.1
28
2.9
7.4
60
1.9
7.0
3.4
4.5
1.6
Snowmelt/rain
Dec. 1-4
172.3
15.9
58
2.8
7.5
107
2.8
10.5
4.4
7.7
2.8
Snowmelt/rain
Dec. 6-7
107.2
12.5
39
3.1
7.5
99
3.5
7.9
4.2
7.1
2.5
Snowmelt/rain
Dec. 10-15
6,717.9
15.6
42
1.8
7.1
57
0.3
3.2
3.1
3.3
1.1
Rain
1978
Jan 5-9
5,874.6
9.8
29
1.7
7.2
57
0.5
3.3
2.2
2.3
1.2
Snowmelt/1imited rain
Feb. 3-7
6,699.8
12.7
37
4.2
7.3
53
0.4
3.4
1.9
2.0
1.0
Snowmelt/rain
Feb. 26-Mar. 2
1,417.5
8.1
21
2.8
7.5
71
0.3
4.7
2.0
4.8
1.5
Snowmelt/rain
Mar. 8-9
1,067.6
10.8
28
2.1
7.4
65
0.3
4.8
1.9
5.1
1.5
Rain
Mar. 12-15
1,152.4
5.3
22
1.7
7.5
67
0.6
4.8
1.7
4.3
1.5
Snowmelt
Apr. 1-7
1,518.6
13.5
35
2.5
7.5
85
0.4
5.6
1.9
7.5
2.4
Rain/sleet/snow
Apr. 16
122.7
15.9
38
3.1
7.6
100
0.2
7.5
2.0
9.8
3.2
Snow/hail/rain
Apr. 27-28
166.4
16.2
41
3.5
7.6
122
0.2
9.1
2.1
11.7
3.7
Rain
May 15-16
113.0
21.0
53
5.3
7.3
150
0.4
8.2
2.3
13.5
4.5
Rain
July 4
6.3
43.8
127
8.9
7.4
299
19.4
23.0
24.1
10.6
6.7
Rain
Total delivery
25,505
14.6
41
3,1
kg/ha—
0.6
5.0
2.7
4.2
1.5
Baseflow
delivery 12,098 5.5 18 1.4 0.3 2.8 3.2 1.1
-------
TABLE D-4. OXYGEN DEMAND, PH, SC, CL, AND CATION DELIVERY BY RUNOFF FROM THE ROCK CREEK
CHECK WATERSHED FOR WATER YEAR 1978
Water
Event dates
delivery TOC COD BOD pH SC
CI
Na
K
Ca Mg
Event type
m3 —Average mg/1- pmhos/ Average mg/1
cm
1977
Nov. 25-27
14.9
9.7
25
2.9
7.4
20
0.3
2.0
2.1
1.0
0.6
Snowmelt/rain
Dec. 1-3
15.3
13.3
39
2.9
6.6
22
0.4
1.5
2.0
2.7
1.1
Snowmelt/rain
Dec. 6-7
4.0
13.5
39
0.2
7.0
23
0.7
1.4
1.7
2.4
0.8
Snowmelt/rain
Dec. 10-16
143.0
8.7
27
1.5
6.8
23
0.1
1.9
1.7
1.4
0.6
Rain
1978
Jan 5-9
89.3
7.5
23
1.6
6.7
27
0.3
2.0
1.3
1.9
0.7
Snowmelt/1imited rain
Feb. 2-7
81.6
10.1
29
3.8
7.1
30
0.3
2.0
1.3
2.2
0.8
Snowmelt/rain
Feb. 26-Mar. 1
7.2
8.9
23
3.2
7.2
41
0.2
3.7
1.5
1.7
0.9
Snowmelt/rain
Mar. 8-9
9.6
12.6
29
1.2
7.3
51
0.2
3.8
1.3
3.0
0.9
Rain
Mar. 12-15
5.5
4.0
14
2.0
7.2
35
0.3
3.2
1.1
2.8
0.8
Snowmelt
Apr. 1-7
23.6
18.3
49
2.9
6.9
29
0.4
2.6
1.2
2.9
1.3
Rain/sleet/snow
Apr. 16
2.5
21.6
55
3.6
7.0
27
0.1
3.0
0.9
2.8
0.9
Snow/hail/rain
Apr. 27-28
4.2
24.3
45
3.8
6.7
34
0.1
4.0
2.1
6.7
2.1
Rain
May 16
5.8
21.2
47
6.7
6.9
59
0.1
3.1
2.3
4.9
1.4
Rain
Total delivery 407.0 4.5 13 1.0
kg/ha
0.1 1.0 0.7 0.8 0.3
-------
TABLE D-5. OXYGEN DEMAND, PH, SC, CL, AND CATION DELIVERY BY RUNOFF FROM THE
ROCK CREEK MAIN WATERSHED FOR WATER YEAR 1979
Event dates
Water
delivery
TOC
COD
BOD
CI
PH
SC
m-
-Average mg/1-
pmhos/cm
1978
Nov. 4
0.9
36.7
67
8.9
16.9
7.3
302
Nov. 17
6.0
37.5
94
8.8
28.1
7.3
334
Nov. 30-Dec.
4 65.6
8.2
26
1.9
4.5
7.3
148
Dec. 11
96.7
4.0
19
1.4
1.6
6.9
69
Dec. 23-24
68.4
7.6
23
2.5
1.6
7.4
121
1979
Feb. 6-7
51.4
13.6
29
4.8
2.8
7.2
136
Feb. 9-14
12,523.2
15.5
49
2.9
0.9
6.7
56
Feb. 18-20
1,254.6
8.9
30
1.5
0.9
7.0
73
Feb. 25-28
5,012.5
9.2
28
1.4
0.5
7.0
60
Mar. 4-8
4,968.2
6.2
26
1.5
0.5
7.0
61
Mar. 15-18
1,066.5
9.1
37
2.1
0.7
7.3
71
Mar. 27-28
532.2
10.5
45
3.5
0.7
7.4
84
Apr. 2-4
1,001.4
11.6
28
1.8
0.3
7.6
78
Apr. 6-10
2,510.2
15.0
33
2.4
0.4
7.7
75
Apr. 12-13
675.4
14.0
35
2,3
0.2
7.7
80
Apr. 16-17
631.8
13.0
39
2.4
0.3
7.7
91
Apr. 23-24
623.5
14.1
37
2.9
0.4
7.8
106
May 4-9
3,926.8
17.0
35
3.0
0.3
7.7
76
kg/ha
Delivery
total 35,015.0 20.5 60.2 8.6 1:1
Baseflow 5,618.0 2.7 8.4 0.7 0.3
-------
TABLE D-6. OXYGEN DEMAND, PH, SC, CL, AND CATION DELIVERY BY RUNOFF FROM THE
ROCK CREEK CHECK WATERSHED FOR WATER YEAR 1979
Water
Event dates delivery TOC COD BOD CI pH SC
m3 Average mg/1 pmhos/cm
1978
Dec. 3-4
10.2
6.9
16
3.3
0.1
6.3
13
Dec. 11
18.9
3.7
18
1.0
0.2
6.1
9
Dec. 23-24
11.1
6.8
22
2.3
0.2
6.4
13
1979
Feb. 6-7
2.9
17.6
42
4.8
0.1
7.4
23
Feb. 9-15
170.1
6.6
17
1.5
0.2
6.5
16
Feb. 17-20
12.1
13.5
32
2.0
0.3
6.6
23
Feb. 25-28
42.4
8.2
27
1.3
0.5
6.5
24
Mar. 4-7
15.8
6.0
27
1.5
0.3
6.7
28
Mar. 16
1.7
11.2
44
2.9
0.2
6.9
37
Mar. 27-28
6.4
16.6
65
3.9
0.4
6.6
34
Apr. 2-4
4.7
11.3
36
1.7
0.6
7.2
32
Apr. 6-9
15.1
18.5
44
2.7
0.3
7.2
31
Apr. 12-13
4.2
16.4
46
3.8
0.5
6.6
27
Apr. 16-17
3.9
18.2
55
3.6
0.2
7.2
31
Apr. 24
6.7
18.8
53
3.9
0.2
7.0
39
May 4-6
43.9
18.8
40
2.9
0.3
7.3
30
kg/ha
Total delivery 370.0 4.0 10.69 0.8 0.1
------- |