EPA-905/9-74-003
                               -3* 	 <\?
                 U^ DIVIRONMBaAL PROTECnON AfflKY
             GREAT 1MB MT1A11VE CONTRAQ PROGRAM
                                         APRIL 1974

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      SAGINAW BAY:  AN EVALUATION

 OF EXISTING AND HISTORICAL CONDITIONS
                   by

            Paul L. Freedman
       THE UNIVERSITY OF MICHIGAN

GREAT LAKES RESOURCE MANAGEMENT PROGRAM
            MENTAL PROTECTION AGENCY
      Library, Region V
      1 North tfacker Drive
     Chicago, Illinois 60606
           In fulfillment of

      EPA Contract No. 68-01-1577

                for the

    ENVIRONMENTAL PROTECTION AGENCY
                Region V

Great Lakes Initiative Contract Program
   Report Number:  EPA-905/9-74-003


    EPA Project Officer:  Howard Zar

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This report has been developed under auspices of the Great
Lakes Initiative Contract Program.   The purpose of the
Program is to obtain additional data regarding the present
nature and trends in water quality, aquatic life, and waste
loadings in areas of the Great Lakes with the worst water
pollution problems.   The data thus obtained is being used
to assist in the development of waste discharge permits
under provisions of the Federal Water Pollution Control
Act Amendments of 1972 and in meeting commitments under
the Great Lakes Water Quality Agreement between the U.S.
and Canada for accelerated effort to abate and control
water pollution in the Great Lakes.

This report has been reviewed by the Enforcement Division,
Region V, Environmental Protection Agency and approved
for publication.  Approval does not signify that the contents
necessarily reflect the views of the Environmental Protection
Agency, nor does mention of trade names or commercial products
constitute endorcement or recommendation for use.

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                   TABLE OF CONTENTS







Summary and Conclusions   	   3



Recommendations  	   6



I.   Introduction	  11



II.  Geomorphology	14



III. Hydrology	18



IV.  Contaminant Sources  	  32



       The Saginaw River	32



       The Tributary System of the Saginaw River  .   .  42



         a. Shiawassee River 	  42



         b. Tittabawassee River 	  43



         c. Flint River	44



         d. Cass River	45



       Au Gres River	45



       Rifle River	45



       Tawas River	46



       Pine River	47



       Kawkawlin River    	  47



       Sebewaing River    	  48



       Other Contaminated Sources  	  48



V.   Physical and Chemical Parameters 	  49



       Alkalinity	61




       Biochemical Oxygen Demand  (BOD)	64



       Calcium	65



       Chlorides	67



       Conductivity 	  70

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       Dissolved Oxygen   	   72



       Hydrogen Ion Activity 	   75



       Magnesium	77



       Nitrogen	78



       Phosphorus	81



       Potassium	85



       Silicon.  .............   86



       Sodium ..............87




       Sulfates	89



       Temperature	90



       Trace Metals	92



       Transparency 	   93



       General Conclusions   	   93



VI. Biological Considerations   	   96



       Coliform	96



       Benthic Fauna   	   98



       Plankton and Macrophyte Communities  .   .   .   .103



       Fish	106



Appendix A-Persons and Agencies Contacted   ....  121



Appendix-B Annotated Bibliography  	  122

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                  Summary and Conclusions
     The water quality in Saginaw Bay has deteriorated from its
natural Lake Huron character through man's overburdening use.
Both the physical-chemical and biological characteristics indicate
similar conditions and trends.
     Chemically, Saginaw Bay is blighted by high concentrations
of dissolved solids originating from the Saginaw River system.
Concentrations are generally higher in the inner bay.  A decreas-
ing gradient exists outward as the Lake Huron water dilute their
content.  Distributions of the concentrating ions in bay surface
waters tend to follow the flow of the contaminating Saginaw River
as it is guided into the inner bay by the changing winds.  Chloride
ions exhibit a severe breach of natural water quality with average
concentrations in the inner bay over fivefold those of the back-
ground Lake Huron values.  Other ionic concentrations including
potassium, sodium, calcium, and magnesium and other indicators
such as conductivity and alkalinity suggest the same phenomena.
     Excessive nutrient concentrations are also characteristic
of Saginaw Bay.  Both nitrogen and phosphorous are in sufficient
levels to support prolific growths of algae.  Total phosphorous
concentrations are over four times those of Lake Huron.  The
distribution of phosphorous (and potassium) exhibits high concentrations
originating from the Saginaw Riveryas do other ions, and remains
predominantly in the more coastal regions of the inner bay.  However,
a tongue of low phosphorous concentration water extends through
the central portions of the bay, and higher concentrations are also
often noted along coastal regions in the outer bay.  This suggests

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significant sources of runoff from all land areas surrounding the



bay and interaction with the sediments in the shallower waters.



     Chemically, the system's major contaminant source is the



Saginaw River.  Other tributary and industrial sources add what is



usually considered to be minor contamination, except in the local



environment. Questions now arise as to the significance of other



sources with regard to nutrient concentrations.



     Overall, the data is insufficient to quantitatively document



any changes in bay quality with time.  The available data does



suggest, however, the the bay water quality may have been deter-



iorating up until the 1950's with slight improvements beginning



in the 1960's.  These conclusions are very speculative and were



drawn from  limited information.



     The biologic communities of Saginaw Bay also are indicative



of poor water quality.  The deterioration and change in the bio-



logic community can be attributed to primarily two factors.  One



is the change in water quality.  The organisms respond to this by



producing a community that is best suited for the now altered en-



vironment.  The second is the invasion of new species to the system.



Their predation and direct competition for the available food supply



cause alterations in the biologic communities.



     The existing benthic fauna of the bay indicate stressed and



pollutional conditions.  The pollution tolerant oligochaetes are



the dominant  group in the bay, demonstrating exceptionally high



numbers in  the  inner bay.  Population density distribution of



oligochaetes  is governed by bottom type  and water quality.  Their



high opulation  may be a result of their  adaptability to  low dis-



solved  oxygen levels and high rates  of sediment deposition.  In

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the outer bay, amphipods predominate with a depth 'regulated dis-



tribution.  Midges are also common.   These two organisms generally



prefer more dissolved oxygen and a thinner sediment layer,  such as




is found outside of the inner bay.



     Overall, the. benthic fauna of the bay indicate decreased en-



vironmental quality, particularly in the inner bay.  Indicative



evidence includes the increase in oligochaete predominance, the



decrease in clean water types, and the disappearance of the once




common mayfly population.



     Saginaw Bay's fish community has also been heavily altered,



particularly in the last half century.  The commercial fishing



industry has been severely curtailed.  Species composition has



changed dramatically to low value fish, and fish production has



steadily decreased to its present low.  Lake trout, walleye,



whitefish, and lake herring once represented the bay's major re-



sources; today they are scarce.  Carp and yellow perch now compose



the majority of the commercial catch.  Causes for these changes



include changes in the foodweb, predation and competition from



invading marine sea lamprey and alewives, changes in habitat, com-



mercial fishing exploitation, and changes in water quality.



     Saginaw Bay is also subject to excessive algal growths.



Phytoplankton concentrations are eight times the value normally



found in Lake Huron, while carbon fixation rates were fifteen to



thirty times greater.  Ceratium is the dominant genera, although



Microcystis and Aphanizomenon are common.  Diatom populations were



not found to be common although the only significant survey was



taken during the summer months.

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     Numerous other serious problems exist in the bay but are not



quantitatively documented by water-quality data.  The problem of



siltation has continually been termed severe and the associated



problems of turbidity and sediment deposition affect water quality.



The list of causative factors includes river and bay dredging, shore-



line erosion, excessive algal growths, wind deposition of soils, and



wave action churning up the sediments.



     Thermal enrichment is also considered by many to be a poten-



tial problem.  Thermal contamination from the Saginaw River  (muni-



cipal and industrial discharges, particularly from power plants)



has prompted these concerns.  Disruption or destruction of the



normal biological cycles is feared and adverse effects have already



been noted in localized areas.



     Occasional oil and chemical spills have been reported resulting



in fish and wildlife mortality and fish tainting.



     Water supply problems have also been realized. Filter clogging,



taste and odor, and corrosion are among the major concerns.





               Recommendations for Future Work



     Despite Saginaw Bay's prominence as a natural resource,



insufficient work has been performed on monitoring its water



quality.  The data is often inadequate to authoritatively document



trends in water quality, both spatially and temporally.  With the



institution of the federal NPDES discharge system and efforts by



federal, state, county, and municipal governments as well as



industry to improve wastewater treatment, the degree of contamina-



tion to Saginaw Bay could change significantly in future years.



The present array of information is grossly inadequate to predict

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any changes in bay water quality.  Numerous important questions posed



are now unanswerable.  For example, if municipal and industrial



discharges were forced to conform to increased phosphorous or



nitrogen removal programs, what would be the effects on water



quality?  How would the concentrations in the bay change?  Would



productivity and algae concentrations decrease?  Would they fall to



acceptable levels?  How would changes in algal concentrations change



turbidity and, consequently, reflect on its own productivity?



Would decreases in primary productivity affect fish populations?



What would be the difference in effects between a local versus



regional program?  Using only the present array of information



available on the bay, such questions cannot even begin to be



answered.  It is for these reasons that intensive limnological



monitoring and modeling programs are recommended.  The application



of such models would allow us to make accurate predictions of answers



to the various questions posed.  It would enable us to assess the



effects of new water-quality standards and enforcement programs.



The relative importance of various contaminant sources to the bay water



quality could be quantitatively evaluated.  Thus, future decisions



regarding discharge requirements and water-quality management could



be rationally established.



     The institution of any predictive methodology necessitates



large amounts of water-quality data for verification.  An unveri-



fied model is of no value.  Presently, the necessary data for veri-



fication does not exist.  Physical and chemical parameters have



been comprehensively sampled only once, and that occurred over



17 years ago.  Since then the bay has been sampled; however,



typically no more than six stations were involved.   (One possible

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exception to this is the chloride data, periodically collected



by Dow Chemical Co.).  The availability of biologic information on



the bay is slightly better.  The benthic resources have been



adequately documented.  The fish resources have been satisfactorily



reported by the U.S. Department of Interior Fish and Wildlife



Service; however, emphasis has been placed only on the commercial



fisheries.  Also, only limited information is available on the



spatial distribution of fish.  Plankton and productivity informa-



tion is presently severely limited.  No relevant comprehensive



survey exists.  Because of these inadequacies, the following re-



commendations are made so as to allow application of existing



predictive methodologies for water-quality management.



     A two-year synoptic survey should be instituted for the



bay similar to the 1956 survey reported by Beeton et al.  (1967).



Sampling should encompass the entire bay at surface and subsurface



levels.  This information is necessary to determine subsurface



circulation and its relation to surface conditions.  All such



information would be valuable in establishing a verified Saginaw



Bay circulation model, a requisite for all modeling efforts.  Thus



far only qualitative information is available concerning the



circulation; much more needs to be known.  The sampling program



should also place particular emphasis on obtaining information



from shallow waters, an area that has been largely neglected in



earlier studies.



     Full nutrient analysis should be performed routinely, inclu-



ding all  forms of nitrogen, phosphorous, and silicon.  Such com-



plete information is presently not available from any one survey.

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 Other  standard  limnological parameters must also be routinely
 measured.   Trace metals  analysis  should be carried out on a
 limited  basis to establish its relative importance and document
 any  violation of standards.
     In  respect to biologic sampling, plankton information is
 needed.  A  year-round  sampling program of both phytoplankton
 and  zooplankton should be instituted.  Complete taxonomic iden-
 tification  studies are essential.  Measurements should also in-
 clude  total productivity and carbon and nitrogen fixation rates.
     The benthic resources of the Saginaw Bay have already been
 satisfactorily  documented; the most recent comprehensive study
 having been carried out  in 1967.  Limited additional studies
 should only be  carried out to evaluate recent changes in the com-
 munities and document  local environmental effects.
     The fish resources of the bay have also been heavily monitored.
 The  continued examination of fish communities should be left up to
 the  appropriate governmental agencies.  Limited fish studies
 may  be needed and are  recommended in localized pollution troubled
 areas.
     Emphasis in the sampling study should include not only open
 water stations but especially coastal stations near contaminant
 sources.   Monitoring should be carried out at the mouths of all
 discharging rivers and outlets for industrial discharge.
     Further work also needs to be done on the Saginaw River.
Although sufficient data is available at the river's mouth, very
 limited data exists at upstream stations.   Monitoring of the entire
 length  of the river should be instituted.   This would facilitate
accurate  evaluation of individual contaminant sources from within

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                              10
its watershed.
     It should be noted here that these are only general suggestions;
the actual number, distribution, and frequency of the sampling
program should be made compatible with the specific requirements
of any modeling effort.
     Modeling applications should be directed toward evaluation of
existing or potential problems identified within the bay; the prominent
concerns being high dissolved solids, excessive nutrient and
phytoplankton concentrations, thermal enrichment, turbidity
and siltation, and coliform bacterial conditions.

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                              11





                      I.  Introduction





     The Saginaw Bay region (Figure 1) has been recognized



as a highly productive and valuable ecosystem.   It facilitates a



mixture of outstanding recreation, prosperous industries, and some



of Michigan's best agriculture.  It still, though, maintains a



significatn population of aquatic and terrestrial wildlife.  In



recent years, some attention has been focused on the area pointing



to decreased environmentla quality and a loss in potential for resource



utilization.  Particular emphasis has been on the bay itself and its



tributary system.  These claims have been prompted by such factors



as an increase in bay water salinity, decrease in commercial and



recreational fish production, an excess of algal growths, and changes



in fish and benthic faunal species.  Man's overburdening use of



the region's resources and his oversightedness with regard to



preserving it may have been one cause.  The clarification and



documentation of these claims has been the impetus of this study.



     The intent of this project has been to compile and evaluate



existing information on Saginaw Bay and document its present status.



Water quality and trophic status have been evaluated with regard



to physical, chemical, and biological parameters.  Efforts



were made to identify the community structure of aquatic plant



and animal populations.  Further emphasis has been placed on




the identification and nature of water-quality variations and



trends and the impact of contaminant sources on the system.



     To attain these objectives, the appropriate governmental



agencies and scientific journals were surveyed to collect all



relevant information.  An enumeration and synopsis of these



efforts is in appendixes A and B, and includes a list of all

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                                                      Lt».o»ft
Figure  1  — Saginaw Bay Region

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                              13
agencies and persons contacted and an annotated bibliography of



the information obtained.

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                              14

           II.  Geographical and Industrial Setting
        (Geomorphology of the Basin and Its Features)
     Saginaw Bay is an inland extension of the western shore of
Lake Huron, projecting southwesterly midway into the southern
peninsula of Michigan.  This shallow arm is 26 miles (42 km) wide
at its mouth between Point Aux Barques and Au Sable Point and
approximately 51 miles (82 km) long, measured from the Saginaw
River to the outer entrance of the bay.  The bay narrows to a
minimum width of 13 miles (21 km) between Lookout Point and Sand
Point.  At this constriction, a broad shoal from Charity Island
to Sand Point divides the bay into what is termed the inner and
outer bay.  The bay's 1,143 square miles (2,960 km2) of surface
area are equally divided between the inner and outer bay (Figure
2).  The inner or southern zone is much shallower, having a mean
depth of 15 feet  (4.6 m)  and maximum depth of 46 feet (14.0 m),
as compared with the outer bay's mean depth of 48 feet (14.6 m)
and maximum depth of 133 feet (40.5 m).  As a result, the inner bay
contains only 30% of the total bay water volume.  Calculated on a
volume basiSj57.1% of the total bay has a depth of 24 feet or
less while 34.2% has a depth of 12 feet or less.  (Beeton et al.,
1967).
     Within the bay there are several islands.  The most prominent
include the Charity Islands, located in the center of the bay, and
several lowlying marsh-surrounded islands, located south of Sand
Point  (South, Stony, and Katechay).
     Shore character variation is moderate.  The western shores
of the outer bay are primarily sand with a few rocky outcrops near
Point Lookout.  The eastern shores north of Sand Point are sandy,

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Figure 2 — Saginaw Bay Area Divisions
            as Discussed Within the Text.

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                               16
grading rapidly into rocky shores east of Hat Point.  South of



Sand Point and around to Lookout Point the shore areas vary



from predominantly marsh to low, sandy ridges.  North of Lookout



Point the shores are primarily sandy with occasional rock up-



croppings.



     Geologically, Saginaw Bay has been considered a shallow exten-



sion of Lake Huron.  Following the final retreat of the Pleistocene



Ice, the Saginaw Bay region was covered by glacial Lake Saginaw.



As the lake receded to its present boundaries, it exposed lucastrine



sediments which are marked by today's sand beaches.  The bay cuts



into a large formation of bedrock primarily from the Mississippian



and Pennsylvanian periods.  It is unlikely, however, that these



preglacial rocks contributed significantly to the present sediment



structure of Saginaw Bay.  Most of these sediments have been



removed by currents, and bare rock has been exposed by wave action.



The Pleistocene glacial till that today define the majority of the bay



bottom.  These deposits of quartz, sand, gravel, and silt have



by now been locally shifted and sorted by bay currents.  Extensive



sandy flats exist south of Wildfowl Bay and west from the Saginaw



River to Point Au Gres.  An extensive reef area, Coryeon Reef,



exists from Charity Islands south to just north of the Quinicassee



River mouth.  It is a gravel and sand bar with a ridge of 6 feet



(1.8 m) and is separated from shore by water of a depth greater



than 10 feet (3.2 m).  Overall, the inner bay is dominated by



extensive shallows  (Beeton et al., 1967).



     Today, land usage in the bay's basin is diverse.  Agriculture



is the major land consumer, encompassing approximately 50% of

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                               17
total basin acreage (Kimball and Bachman, 1969).   Of this, the



majority is cropland.   In contrast, only 3.5% of the land is urbanized,



and yet the area still commands a significant industrial network —



the automobile, chemical, mining, and food industries are the most



prominent.  Although only 1.2% of the land areas are designated



for recreation, 34.2%  of the region is still considered forested.



These lands, the marshlands, and other undeveloped acreage possess



significant wildlife resources.  The area supports numerous aqua-



tic and terrestrial fur animals, upland game and white-tailed deer,



and is a nationally known waterfowl preserve.  The basin supported



an estimated population of 1,235,920 in 1970, demonstrating a growth



of 15.9% over 1960.

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                                18
                         III.   Hydrology



      Four basic  hydrologic  factors  control  the  net supply of



 water to Saginaw Bay:   runoff  (drainage), precipitation,  ground



 water flow,  and  evaporation.   Saginaw  Bay receives drainage  from



 a  basin  seven times  larger  than  the bay  itself  or  over  8000  square



 miles (5.12  million  acres or approximately  21,000  km2).   Of  this



 drainage,  the major  source  is  the Saginaw River Basin,  drawing from



 6,222 square miles of  land, nearly  80% of the total bay's basin.



 The  major tributary  rivers  of  the bay  and their drainage  character-



 istics are listed in Table  1.



      The majority of the watershed  is  covered with Podzol-type



 soils, similar in organic character.   The degree of soil  compac-



 tion or  tightness differs considerably,  though.  Depending on the



 soil structure,  precipitation  can either percolate quickly and



 easily or run off.   The flow characteristics, then, of  each of



 the  tributaries  can  differ  considerably, and generalizations con-



 cerning  flow stability cannot  be made.   More will  be  said concern-



 ing  each tributary in  the following chapter on  contaminant sources,



 as each  river will be  discussed  separately.



      The average annual water  levels in  Saginaw Bay are controlled



 by the Lake  Huron water level  and,  hence, are a function  of water



 inflow from  Lake Superior and  Lake  Michigan, outflow  through St.



 Clair River,  and annual climatology.   Within a  one-year period



 the  monthly  average  lake levels  do  not vary much from the summer



 high levels  to the winter low  levels  (Corps Eng.,  1952).   The bay



water  level can,  though, demonstrate very short-term,  rapid, and



large  fluctuations as a result of wave runup,  wind driven tides,

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Table 1:  Major River Drainage to Saginaw Bay
River and
Station Locations
Au Gres R
(at National)
East Branch Au Gres R
(e t Mclvor)
Kaw/cawlin R
(at mouth)
Pigeon R
(near Pigeon)
(near Owendale)
Pine R
(by Standish)
Pinnebog R
(at Oliver)
Rifle R
(near Lupton)
Total
Drainage
Area sq m
420
(169)

(84)
224
(224)
156
(86)
(55)
99

171

387
(56.8)
(at Selkirk) ' (117)
(20 miles from mouth) (320)
Saginaw R* 6222
1) Cass R ' 931
(at Cass) i (370)
(at Wahjamego) ; (637)
2) Flint R j 1300
(near Otisville)
(near Flint)
(near Fosters)
3) Shiawassee
(at Linden)
(at Byron)
(at Owosso)
4) Tittabawassee
(531)
(954)
(1120)
1160
(81.2)
(368)
(538)
2620
(at Midland) i (2400)
Chippewa
(near Midland)
Dates ;
i
of Records

50-present
i
50-present :

65-present >

46-52
52-present

none

none

56-71 .
50-present
36-present


47-present
68-present

52-present
32-present
39-present

67-present
47-present
31-present

36-present
;
(597) | 47-present
Average
Flow
cf s

97.5 (21 yrs)

63.8 (21 yrs)



64.2 ( 5 yrs)
28.0 (19 yrs)

calculated es

calculated es

91.7 (21 yrs)
143 (21 yrs)
306 (35 yrs)


190 (24 yrs)


259 (19 yrs)
533 (39 yrs)
668 (27 yrs)


237 (24 yrs)
310 (40 yrs)

1569 (35 yrs)

424 (24 yrs)
: Momentary
Max Flow
cfs

2350

1310

2575

3700
2550







1330
2760
5340


8460
7610

6150
14900
19000

262
2900
; 6240
,
34000

i 8510
i
Minimum Limited
DailyFlow Flow Info
cfs cfs

5.9

22

0

0
.1

_ _ _ _ _ =i£


— _ - _ - "?n H
_su ,_

48
55
75


.5
22 ave'^400

4.3
9
27

2.8
3.55
2

111

44
                                                                           vo

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                              (Table 1 cont'd)
5) Saginaw
Sebc>waing
149
110
42-present*
i I
1 ' !
*
 Information available only during high water due to unusual hydraulic characteristics
 of the River.

Additional direct bay tributaries not listed include:  Quinnacassee River, Saganing
River, Silver Creek, Squaw Creek, Wiscoggin Drain, and Whi£e Feather Creek.

Compiled from the following sources:
    1.  Environmental Protection Agency STORET Data retrieval system 1973 retrieval.
    2,  USGS Water Resources Data for Michigan Part 1, Surface Water Records 1971.
    3f  U. S. Dopt. Interior.  National Estuary Study, Vol.  3,. 1970.

    4.  Water Resource Commission, Michigan DNR, Interim Water Quality Management Plan    £J
        for Saginav River and Huron Western Shore Minor Basins, April 1971.

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                                21
 seiches,  etc.  According to the Great Lakes Pilot  (1956),  "The



 Saginaw Bay  is subject to sudden changes in wind.  A northern



 gail can  drive water into the bay so as to raise the level at the



 mouth of  the Saginaw River 3 to 4 feet in less than as many hours,



 while a southwest wind lowers the level at times sufficient to



 cause large vessels to run aground in the channel."  High bay



 water levels have at times created significant shore erosion prob-



 lems.  In 1951 the Corps of Engineers (1952) estimated $150,000 damage



 in the area  from Bay City to Port Huron and $1,268,500 damage



 from Bay  City to the Straits of Mackinac which included Alpena



 Bay as the only significant beach erosion area outside of Saginaw



 Bay.  This shore erosion results not only in property damage but



 contributes to water-quality degradation.  The eroded shore



 material  increases turbidity and adds unoxygenated mass to the



 water-sediment system.




     Saginaw Bay undergoes the usual annual temperature cycle



 experienced by most fresh water>temperate zone lakes.  The deep



 water temperatures remain at or near the point of maximum density,



 4° C (39° F) year-round.  The shallow and surface waters, though,



 undergo thermal change from season to season.  In the spring the



 total water mass warms from 1° C to 4° C and produces a vertically



 homothermous condition.  Thereafter, the shallow waters tend



 to warm more quickly, the degree depending on local conditions.



 Only in the outer reaches of the bay does a well-formed thermo-



 cline persist in the summer and fall; although, temporary stratifi-



 cation does occur within the bay during the summer.  Complete



winter ice cover and limited stratification is typical of the bay

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                               22
during winter months.  Ice forms in December and usually deterior-



ates by March.



     Because of the bay's mid-continent, mid-latitude location,



it is subject to weather conditions.  The weather is moderated



slightly due to the obvious "lake effect."  The bay lies in the



pathway of storms that sweep across the Great Lakes region from



west to southwest.  The result is frequent and, at times, rapid



weather changes, extreme seasonal variation in temperature, and



a fairly even annual distribution of precipitation    (Figures 3



and 4).  The mean yearly temperature is 8.35°C (47° F).  The



summer months experience a mean maximum temperature of 27.5° C



(81.4° F) and a mean minimum temperature of 14.6° C (58.3° F) .



     The winter months are dominated by the colder Canadian air



masses resulting in slightly less precipitation and humidity.



Low temperatures can drop well below zero.  The average snowfall



is 102.6 cm, 40.4 inches  (Figure 5), with the ground  freezing



to a depth of .3 to 1  (1 to 3 feet).  The average frost-free



season is only 150 days  (May to early October).



     The annual precipitation  (mean 74.6 cm, 29.4 inches) is well



distributed throughout the year with monthly averages ranging from



3.6 cm  (1.44 inches) in January to 8.2 cm  (3.23 inches) in June




(See Figure 4).



     The winds principally originate from the WSW and SW directions




with the least common wind directions being east  (Figure 6).  The



prevailing westerlies have a mean speed of 15 to 20 kph  (9.4 to



12.5 mph).  The highest mean wind speeds occur during March when



the most frequent WSW winds average 24.8 kph  (15.5 mph).

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  90.
  80-
  70_.
f_ 60 _
w
( .
r-i
(0
frf
  30..
  20_
  10..
                                                                                                                t>0
          Jan.      Feb.
Mar.
April
May
Juno     July     Aug.
    MONTH
Sept,     Oct.     Nov.      Dec.
                                       .  Monthly Moan Temperature at the
                                       Day City Sewage Plant, Bay City, Michigan,
                                       (Sixty- three Year Period of Record)
                                Figure 3 source:   Consumers Power 1972

-------
    4 -4
                                 24
                                       3.23
    3-
z
o
a.
M
u
o
CO
    2_
1.44  1.44
    1-
           1
           ;
       I
       z
       i
       1
                     1.75
                      MS
                           2.22
                              s
                                        K-
                                                        2.84
                                                  2.68
                                                              2.39
                                             2.19
                                                          2.12
                       1.50
                        PI
                         I
                         S
          Jan.  Feb.
            Mar.  April  May   June July
                                MONTH
                         \
Aug.  Sept.  Oct.  Nov.  Dec.
                       Mean Total Monthly  Precipitation at the
                       Bay City Sewage Plant, Bay City, Michigan.
                      (Sixty-four Year Period of Record)
                      Figure  4 source:   Consumers Power 1972

-------
                                25
   9.
   8,
^  7
§  6  ,
00  5_
w
   4_
   2 _
         9.4
          a
               9.7
      1
      1
                5§
Jan.   Feb
            7.3
            ;S
            iii?
            ^
                                                                8.2
                                                                    3.3
                           2.0
i
                                                                          M
                                                              0.2
                    Mar.  April  May   June   July   Aug.  Sept.  Oct.
                                        MONTH

                       Monthly Mea- "i.cr.'fall at the
                       Saginaw Airport •,  Saginaw Michigan.
                       (Sixty-three Year Period of Record)

                    Figure 5 source:   Consumers Power 1972
                                                           Nov.  Dec.

-------
                                                  o

                                                 I
           •
       o,
     O
     c
j
0}



                     n
                     c
      o
     t
                       S-
£
                    m
                    w
                  t

                 iO
                a
                o
                   O
 3



n
                                 •o
                                 m
                                     m
                                     a
              m
             o
             n-
            o
                                                    to
                                                  S
                                            Q

-------
                               27
     Wind conditions, along with the strong Lake Huron circula-



tion, play prominent roles in determining the highly variable



water circulation conditions in Saginaw Bay.  The prevailing cir-



culation is speculated to be counterclockwise, typical of a north-



ern estuary.  Lake Huron waters enter from the northeast flow along



the bay's north shore, while the Saginaw River flow hugs the



southern shore and then exits to Lake Huron.  The prevailing west



and southwest winds and the rotation of the earth tend to rein-



force speculation on this circulation.  Surface currents tend to



be closely related to wind conditions, reorienting their directions



with respect to changing winds in relatively short periods of



time.  Because of the relative shallowness of the bay and its



limited stratification, it is suspected that subsurface currents



are highly influenced by surface flow.



     Johnson  (1958) carried out extensive surface current studies



on Saginaw Bay.  In 1956, 2,650 drift bottles were released in



Saginaw Bay and adjacent waters of Lake Huron.  From the recovery



results Johnson concluded, "that the dynamics of the bay are



closely related to the highly variable meteorological conditions



and that the surface currents are in a continuous state of



change.  For this reason we must state specifically under what



conditions any particular surface currents  pattern was  found."




Johnson further demonstrated that although  surface currents did



at times resemble what has been termed the  typical currents,  no




pattern persisted over an extended period of  time.  Completely



different current patterns could exist depending on the wind



characteristics  (See Figure  7).  Johnson further documented  the



strong influence of  currents entering the bay from Lake Huron

-------
                                            28
                              —Typical  surf ace-cur rent flow
                       for Saginaw Bay in the suaner of 1956.
     ".—Surface currents in Saginaw Bay
ieter-j.ned fror. travel of'drift bottles
released on August 10, 1956, during a
Period of moderate westerly winds.
       .—Surface currents in Saginaw Bay
determined from travel of drift bottles
released  on October 12-13, "1956, during a
period c£ strong southeast-northeast winds.
                                     Figure  7 source:   Johnson  1956

-------
                               29
which could, on occasion, override the wind-induced conditions.



Johnson made no attempt to study subsurface current, although



he did speculate a close dependence of subsurface flow on surface



currents.



     Chloride surveys by the Michigan Stream Control Commission



in 1935 and 1936  (Adams, 1937) provided good examples of how



current flow tends to follow wind patterns  (Beeton et al., 1967).



By following the high chloride discharge of the Saginaw River,



possible current patterns can be derived.  The predominant north-



easterly winds of May 12-24, 1935 were followed by clockwise



circulation, as indicated by the surveys of May 13-19 and May



20-24, 1935.  A similar clockwise circulation could be seen in



the survey of June 22-25 due to the north, northeast, and south-



east winds.  Counterclockwise circulations resulted from westerly



winds as documented by the winds of June 19-28, 1935 and the sur-



veys of June 24-28 and July 1-4.  From the data it appeared that



the bay circulation could change from a clockwise to a counter-



clockwise circulation in as little as 4 days.  Beeton further



documented the influence of the Coriolis effect on the Saginaw



River.  After entering the bay, the river waters tended to deflect



to the right, as indicated by the higher ion concentrations along



Coryeon Reef, the southeast shore of the inner bay, and the



south shore of the outer bay.  During the winter, ice-covered



Saginaw River flow was unaffected by the winds and tended to also



show a northeasterly flow and subsequent ion buildup, as shown



by the March 1936 chloride surveys.




     Ayers et al. (1956), although primarily concerned with Lake



Huron circulation, was able to draw some conclusions concerning

-------
                               30
Saginaw Bay circulation from their studies.  They suggested that



the bay had a typical counterclockwise circulation with spring



inflow along the northern shore of the bay mouth and outflow



along the southern shore, with both inflow and outflow extending



from surface to bottom.  In the summer the outflow appeared to be



spread out over the surface of the entire mouth while the inflow



was subsurface.  This change from horizontal to vertical circula-



tion is typical of estuaries of similar geographic location.  They



speculated that with the fall breakdown of the thermocline



the system would revert to a horizontal circulation, and remain



as such till the following summer.  This since has been neither



confirmed nor disproved.  Further studies concerning the sub-



surface currents are merited.  Presently E. C. Monahan and A. W.



Green  at The University of Michigan are developing a detailed



mathematical model of the Saginaw Bay circulation.  It was not



complete at the time this article was written.



     Beaton et al.  (1967), using data from their 1956 survey,



calculated flushing times for the bay.  Only the Saginaw River



was considered in the calculations because at the time of the



study  all other direct river discharges to the bay amounted to



only 8% of the flow of the Saginaw River and each also had sig-



nificantly lower ion concentrations.  Flushing times were calcu-



lated  by taking the ratio of accumulated river water in the estuary



to  the volume  introduced daily.  Chloride  content was used to



differentiate  between  the natural lake water and the more saline



river  water.   They calculated flushing times for the inner, middle,



and outer  zones of the bay on three dates, representing the spring,

-------
                               31
summer, and fall.  The corresponding total flushing times were



114 days, 280 days, and 376 days, with an average of 186 days.



Flushing time increased with decreasing flow, the effect being



more pronounced in the inner bay.  Specific figures and detailed



comparisons cannot, however, be relied upon because of variations



in river flow and ion content.  Lakeward transport calculations



were also performed demonstrating, as expected, a decrease with



decreasing river discharge.



     These hydrologic examinations of the interactions between



the Saginaw River and the Saginaw Bay do not, however, reflect



the actual complexity of the system.  Depending on the wind



conditions, barometric pressure distribution, and lake level, the



Saginaw River flow at times can reverse, allowing bay water to



flow inland.  This phenomenon can introduce much complexity and



error into any analysis made.  More concerning this flow reversal



will be presented in the section concerning the Saginaw River.

-------
                               32
                   IV.  Contaminant Sources



The Saginaw River



     The Saginaw River is the major contaminant source to Saginaw



Bay.  Its basin of 6,222 square miles is the largest in the state,



although it drains only 246 square miles directly.  The 22-mile



river is formed at the junction of the Shiawassee and Tittabawassee



Rivers with the Cass and Flint Rivers having entered the Shiawassee



slightly upstream.  Cheboygaining and Dutch Creeks also flow into



the river at intermediate points downstream, draining 100 and 40



square miles respectively.  The river enters the bay at the south-



western end.



     The river has been dredged and used extensively as a commercial



waterway.  This has not, however, prevented its other multifaceted



uses, including fishing, power development, irrigation, water supply,



and park development.  Well over one-third of the land usage in the



basin is devoted to agriculture, yet it still includes highly



industrialized urban areas such as Saginaw, Flint, Midland, and



Bay City.  Other large areas in the basin are occupied by state



and federal game sanctuaries.



     The Saginaw is a slow-moving river, having a gradient of 1



foot per mile or less its entire length.  At drought flows (350



cfs) velocities can get as low as .03 feet per second.



     Stream flow records for Saginaw River are only available



during periods of high water.  The river has unusual hydraulic



characteristics.  Its level will change as much as 3 feet in a



year and on occasion significant level changes can take place



within a few hours as a result of the raising or lowering of



Saginaw Bay by nprtheasterly or southwesterly winds.  These

-------
                               33
changes can cause flow reversals whose effects can at times even



be observed in the river's tributaries.   Flow reversals occur



on 85% of the days, last typically for 3 to 9 hours,  and can be



caused by as little as 1/10 foot change in river height.  The



reversals do not effect the long-term time of passage but



their significance lies in the doubling and tripling of pollutional



loads to the river as it stops, reverses, stops, and then resumes



its original course.  (Time of passage-dye studies, flow reversal-



gauge studies and drought severity studies have been carried out



by the Michigan Water Resource Commission [WRC].)



     As a result of the river's unusual character, stream flows



are usually calculated by adding the flows of its tributaries



and other discharge sources.  The flows typically range from 500



to 8000 cfs throughout a year with a median value estimated grossly



as 1700 cfs and an average of 3850 cfs.



     The Saginaw River receives both municipal and industrial



discharges.  Five municipalities discharge their treated wastes



into the Saginaw River:  Carollton, Saginaw, Buena Vista, Bay City,



and Essexville.  Prior to 1972, only primary treatment with chlori-



nation was maintained.  As of 1972, however, these municipalities



agreed to institute secondary treatment with phosphorous removal.



During a July 1965 WRC survey, Saginaw City contributed 62.7% of



the total 5-day BOD being discharged to the Saginaw River; the



Bay City plant contributed another 32.9%.  All the plants combined



discharged 21,037 Ibs/day of BOD to the river.   The WRC



analyzed composite samples of sewage effluent in the July 1967



survey for a wide variety of parameters  (See Figure  8).  Monthly

-------
                                                                    Figure  8   source:    Michigan  WRC  1971
                                                                                SACINAW RIVER
2-d.ly DOO
5-dsy 000
6-d,iy 00(1
8-rljy 000
10-dJy DOD
10-il.ly (lltcrcd 000
13-tl.iy 000
Fint suijQ k] rote
I'll inwtc 000

con
F> I Icicd COO
pH

Suspended  sol I ds
Suspended  volatile solids
Tota I iol I ds
Total volal I Ic sol I Us

Phenol
Tc
Cu
Nl
Zn

NO: « "02
NOj as NOj
NHJ - N
Org. N.
Ortho POj,
Poly P0|,
Org. POi,
Total  PO/(

Anlonic Ocicrgent
C!

Chloroform Cxtractobte
  Al i phot I cs
  Aromjil c
  Oxygenated
Flow (M.C.D.)
Carroll ton
Survey , '/I Survcv 111 Survey in
92
172 195 78
180
201)
225
130
250
0.10
255
'120 515 397
220
6.8
130 126 121)
110 104 101)
1,170
31)1)

0.00
0.00
0.00
1.9
0.0
p.o
0.0
0.3
0.0
33.0
15.0
30.0
10.0


7.5
225
1)6
3.2
13.1)
23.3
COMPOSITE SEWAGE TREATMENT PLANT EFFLUENT SAMPLES
Saqlnaw Buena Vista
Survcv #1 Survev #2 Survev #3
. 44
76 96 56
81
IOU
111
£2
120
0.085
125
380 1)27 155
120
7.2 7.3 7.6
122 101) 74
80 53 3")
708 812 739
186
0.06 O.OJI) 0.061)
0.00
0.00
0,00
3.0
0.0
0.0
0.0
0.5 0.15
0.0
11)
8
13
3.5
6.5
23
lt.0
1 70 21)3 230
72
5")
6
II
Survcv //I Survey #2 Survey //3
88
121) 188 12}
145
170
187
98
210
0.09
210
360 39") 305
155
7.2
122 87 118
96 60 102
771)
260
0.05
0.00
0.00
0.00
2.2
0.0
0.0
0.0
0.2
0.0
31)
8
36
4.0

1
II
160
37

9.'o
18
Day City
Survev //I Survey 111 Survey //3
1)8
81) 103 91
. 105
130
I1))
68
157
0.07
175
380 294
160
7.3
118 101 82
90 75 70
1,01)0
260'
0.05
0.20
2.1)
0.5
1.3
1.0
0.8
0.3 .
0.3
0.0
13.0 '
12.0
13.0
lt.0
II. 0
28.0
4.0
335
42
17
8
13
Esscxv i 1 It*
Survcv >l \ Survey HI Syr /o;
100
. 157 17) 1
I5/
103
192
110
210
0.11
220
380 390 2
160
7.2
103 83
86 61
766
264
0.05'
0.00
0.00
0.00
1.0
0.0
0.0
0.0
0.2
0.0
28
10
27
11


12
125
l)l>



                               0.2*
                                         O.J*      0.2*
                                                           19.9
                                                                    21.)
21.3    •  0.340     0.311
                                                                                                          0.327
                                                                                                                      8.1)
                                                                                                                               9.0
                                                                                                                                         9.1*
                                                                                        DO
                                                                                        25")
                                                                                                                                                                             to
0.257    0.179     0.2IS
NOTE:   All concentrations  except pH and flow are expressed  In milligrams par liter.  Laboratory determination! for DOD'» were made on  a dcchlorlnated and sccdjd -.ample.
    Survey //I  conducted 0800 on 7/19/65 to 0800 on  7/20/65
    Survey 112  conducted OftOO on 7/20/65 to 0800 on  7/21/65
    Survny in  conducted 0800 on 7/21/65 to 0800 on  7/22/65
   iu:ned flow

-------
                               35
operating reports are also available with limited information for



each of the plants.  Discharge character has, however, significantly



changed since 1972.  Information after this date is not presently



available.



     The major industries that discharge directly to the river



include:  the Chevrolet-Saginaw Grey Iron Divison of General



Motors Corp., the Petrochemical and Bay Refining Divisions of



Dow Chemical Company, Michigan Sugar Company, and Monitor Sugar



Company.  Waste surveys have been conducted on these industries



by the WRC on various isolated dates (See Figure 9).  Each of the



industries has contributed to the high conductivity and total



solids content of the Saginaw River.



     The two sugar companies operate on a seasonal basis (September



to January) and discharge only from October until ice cover and



in the spring during high stage.  In 1965 they constituted over



99% of the industrial BOD loading to the river and, during discharge



time, 35% of the total river BOD loading.



     Other miscellaneous sources of waste discharge to the river



include commercial shipping, recreational boating, dredging, and



storm water overflow from combined sewers which as of 1965 were



in all communities except Carollton.



     The Michigan WRC as part of their extensive 1965 survey of



Saginaw River took numerous D.O. measurements and performed elabo-



rate deoxygenation calculations.  They concluded that they were




two distinct D.O. sags on the Saginaw River, the most severe



occurring below the discharges from the cities of Carollton,



Saginaw, and Buena Vista.  The other sag occurs below Bay City

-------
                                                            Figure  9   [source:    Michigan  WRC  1971]
                                                                           SAGINAU RIVER
 0.0.
 1-Oiy 0.0. 8,
 2-O.iy B.0.0.
 'i-OJy I). 0.0.
 5-Djy B.0.0.
 7-O.iy 8.0.0.
 9-Day U.0.0.
10-Doy O.U.O.
U-Qjy 0.0.0.
K| RMU
C.0.0.
SOI,
Oig.  N
KOj-K
UOj-N
Nil}-!)
Org.  P0l4
COl^
r«
Cl
CHCIj til.
Anlunlc Oi'tcrgciil
Cu
Hi
I'b
HCO)
pll
Phenol
Conduct ivl ly
Tool  Sol Mi
Total  Vol. Solid!
Jus ponded  Sol Ids
Suspended  Vol.  Solid;

Hjxlmum  flow (•• *••»
6.4 5.7
*•*>• »••
216 156
104 100
664 ' —
102
3)9 —
0.488 —
10/25 10/26
10/26 10/27
Site
Survey
#1
140
153
2)0
250
270
275

0.15
380

6.0
0.0
2.0
205
O.I

290
6.8
0.02
1,200
1,036
360
86
78
J.OOB
l.loo
2,016
2.9
10/25
10/26
#2
Survey

•»•>»

	

	
"•"


•i**
7.0
1,150
495
08
70
2,815
1.1)6
1,8)2
2.64
10/26
10/77
Raw
Water
• •»
• «•>•

38

0.9"
0.5
0.7
405
0.2

7.7
0.00
1,020
*28
II
**•
7/20
7/21
Survey Survey
, //I 02
174
193
330
335
340

420

5.0
0.0
2.0
220
0.1

240
6.2.
0.02
1,200
996
136
J.388
247
1,679
2.42
' 10/25
10/26

247

...

—



'("{'I
\ —
.'• 345
'i, 132
• 76
2,312
. 561
1.827
^2.63
10/26
10/27
Raw
Uamr

9.9

...

0.4
0.70
0.4
220
0.2

215
7.7
0.004
1,100
17
9
10/26
10/2?
Dow Chemical Company,
Pet ro'Chr mica) and Bay lU-flninn Division
Day Refining
Crude Unit
Survey Survuy
*l , U2

4.0
7.2
10.0
M.5

60
1.0
0.26
I.I
1.0
0.7
400
0.4
0.00
0.00
0.00.
0,008
1,108
240
40
16.
J.6
10/26
10/27
7.4
8.0

71
87
1.2
0.23
0,3
0.7
0.8
400
0.4
0.00
0.00
170
7.7
• .010
1.004
294
38
21
3.5
10/27
10/28
Day Refining
Cracking Unit
Survey Survey
PL «2

4.8
8.0
10.0
12.0

47
0.9
O.IU
0.3
0.7
300
0.3
0.00
0.00
7.7
0.015
' 000
200
30
IS
10. 1
10/26
10/2
7.4
0.0

50
67
0.6
0.10
0.0
0.2
0.9
V55
-. 0.2
O.UO
• o.oo
1)5
1 7.9
0.015
746
41 '
, JO
; 10.7'
i
10/27
10/2(1
Petro-Choinlcjl
Survey Survey
m in

2.0
6.4
6.8
10.0

51
O.U
0.16
0.4
0.6
1.2
205
0.00
0.00
7.0
0.004
060
222
64
26
. 66.3
io/;6
10/27
7.4
7.6

54
7)
IT?
0.14
0.0
0.2
0.7
775
0.2
0.00
0.00
(1.0
o.oo'i
B30
296
53
65. C
10/27
10/Jfl
ftju Ifctcr
Survey Survey
J\ 1.2
...
5.0
9.0
10. a
12.5


o.a
O.I)
OJ
0.5
1.0
)00
1.2
0.2
0.00
0.00
0.00
7.0
O.OO'i
900
19
S3
10/26
7.5
5.

'•7
67
o.a
o.u
U.I.
0.6
i.i
V75
O.I
0.00
0.00
I4J
7.6
0.001.
2yi
16
eo
kV?;i
                                                                                                                                                                            CTl
HOTCi  All .v.»«e, .«tPt the  MM »!»•«,• pll. M< conductivity «ro
                                                                      •« «9/l.  Conductivity |. . xprm.d ». .lero-HHOS.

-------
                               37
and Essexville.  According to the WRC report, at 1965 levels the



municipal and industrial discharges from Carollton, Saginaw, and



Buena Vista will depress river D.O. to 2.2 mg/1 at drought flow



of 445 cfs and a temperature of 20° C.  The WRC report recommended



that loadings be cut to 4000 Ibs. of BOD/day in order to maintain



a minimum daily D.O. of 4 mg/1.  This is 1/5 of the measured



loading of July 1965.  Similarly, the WRC predicted that the



July 1965 discharges from Bay City and Essexville would completely



deoxygenate the river in drought conditions  (considering



no flow reversal).   The WRC recommended that loadings be cut by



1/3 (down to 1800 Ibs./day) so as to maintain a 4 mg/1 D.O.



concentration.



     Similar calculations were carried out for fall and winter



conditions on the river.  They predicted a D.O. sag falling



to .9 mg/1 below Carollton, Saginaw, Buena Vista, and the



Michigan Sugar Company, but only a minor sag below Bay City,



Essexville, and the Monitor Sugar Company.



     Dissolved oxygen measurements from June, July, and



October of 1965 demonstrated the predicted sags discussed above.



D.O. concentrations rarely went below 4 mg/1; however, these



surveys were not taken during a low flow condition.



     The D.O. profiles and BOD loadings to the river are expected



to have improved since the 1972 implementation of the NPDES system



and installation of secondary municipal treatment.  Verification



of this is not possible for data is not available yet.



     The physical and chemical characteristics of the Saginaw



River have been documented well since 1963  (EPA, STORET), but

-------
                               38
the only major sampling station is at the mouth of the river,



highly effected by flow reversal from the bay.  Temperature, D.O.,



and BOD data is also available since 1950 at various dates and



locations from the Michigan WRC.  All data, however, indicates



the same conclusion.  The Saginaw River water quality is excep-




tionally poor.



     As already mentioned, the BOD and D.O. levels are unsatis-



factory.  The BOD's in heavy pollutional zones often range as



high as 15 mg/1.  At the river mouth much of the BOD has already



been exerted; yet the BOD's still average between 2 and 6 mg/1.



Exceptionally high values have been found in the past below the



sugar companies' discharge and during algal blooms.  D.O. concen-



trations vary widely in the river, often falling below the 4 mg/1



level, yet equally often demonstrating concentrations greater



than 8 mg/1.  The D.O. level is heavily dependent on loading,



water temperature, location, and flow.  Slight improvements in



the D.O. concentrations of the river have been noticed in recent



years  (EPA,  STORET).  This results from implementation of better



treatment facilities within the system and the corresponding



decrease in  BOD  loading.  Concentrations of dissolved oxygen



still occasionally drop below 4 mg/1, particularly  in the summer.



     Chloride levels in the river are particularly  high.  At



the river mouth  the 10-year average concentration was 163 mg/1.



Concentrations often approach 400 mg/1  (See Table 2).  From recent



data, however, it appears that  the chloride concentrations may



have improved, having decreased by as much as  30% from measurements



taken 10 years ago.  Other ions such as potassium and sodium were

-------
Table 2:     Typical Loadings to Saginaw Bay


            of Selected Tributaries
Phos -D Total P NO--N
Flow Ortho as P ,
0) , id) , Q)
cfs tr> O tn o {71 O
c c c a c c
Kj o j rd 0 (u u
MO . M 0 ! M 0
gm/ gm/ j gm/
mg/1 day j mg/1 day j mg/1 day
to ' t
2 .01 1.04 i.02 4.28! .1 2.63
0 250 to .017 x. to .07 x . to .43 x,-
3 .04 104 ;.21 10 1.3 10
j
1 ;
« 0 1.78 '.02 8.01! .01 1.3
.46 1.70
to .60 x. to .87 x, ; to 1.8 x?
2.0 10 1.6 10b i3. 5 i 10
; i 1
.'. : .
Chlorides
i
r a)
Cn O
C! C
m o
M 0
gm/
mg/1 day
11 2.02
to 33 x -
67 10
8 1.52
to 17 x7
24 10
9 2.66
to 67 x7
200 10
46 1.54
to 163 ,XQ
390 | 10
'
                                                                      u>
                                                                      vo

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                               40
also found in high concentrations.  Typical respective concentra-
tions are 6 mg/1 and 70 mg/1.  Sources of contaminating ions
have been attributed to the industrial and municipal discharges
within the basin, particularly those of the Tittabawassee
River.
     Nutrient levels in the river are at elevated concentrations
year-round.  Inorganic nitrogen levels range often as high as
3 mg/1 as N.  Nitrate and ammonia levels vary widely but typical
levels to be expected would be .5 to 1.5 mg/1 N03 as N and .2 to
1 mg/1 NH4 as N  (See Table 2).  Organic nitrogen concentrations
average  .87 mg/1 as N.  Phosphorous levels are equally excessive.
Dissolved phosphorous concentrations usually range from .1 to
.3 mg/1  as P with total phosphorous concentrations often double
or triple.  Nutrients levels do not appear to have improved
significantly in recent years.  Long-term improvements or degradation
cannot be evaluated, since no nutrient data was available prior
to 1963.
     Biologically the Saginaw River is in a deplorable state.
Coliform, plankton, and benthos indicate high degrees of pollution.
Unfortunately, as is the case for all the Saginaw River data,
biologic information is scarce.  The Michigan WRC is responsible
for  the  only significant available study.
     In  the WRC  1965 study, extremely high total and fecal
coliform concentrations were found in much of the river.  They
occurred at all  times of the year, even during periods when
contaminant waste waters were chlorinated.  The highest concentrations

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                               41
were observed after combined storm water and sanitary discharges



to the river.  Total coliform concentration generally ranged



between 1,000 and 500,000 organisms/100 ml with fecal coliform



ranging as high as 60,000 counts/100 mg.  Concentrations were



highest in the areas surrounding the Carollton, Saginaw, and



Buena Vista sewage plant discharges and near the Bay City and



Essexville discharges.



     During the summer months, phytoplankton in the Saginaw



River were extremely productive.  They affected the D.O. and



BOD of the river significantly.  Concentrations in the summer



months were 10 times that of the fall, winter, and spring



values.  Plankton counts well over 25,000 per milliliter were



commonly found in the river during the summer months.  Concentrations



ranged as high as 97,020 per milliliter.  Productivity was measured



during a two-day period in July 1965 and found to reach levels



as high as 2 mg C»2/l/hr.  Highest algal activity was found in



the vicinities of the city discharges.  Most of the algae species



found in the survey were considered pollution tolerant, usually



found in enriched waters.  Large growths of attached filamentous



algae were also noted.



     Primary production in the summer months appeared to be



limited by only the available light energy.  The euphotic zone



was restricted to only 10% of the waters during the summer months.



Light extinction was caused by the algae themselves and other



high sources of turbidity.  Average secchi disc values were  .33



meters.  The high light extinction prevented growths of macro-

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                               42
phytes on the river bottom despite the bottom's strong organic



character and the high nutrient levels present year round.



     Sludgeworms and bloodworms, both highly pollution   tolerant,



composed over 99% of the total benthic population of the Saginaw



River sampled in 1965.



     Overall the Saginaw River is obviously in an unsatisfactory



state, both chemically and biologically.  The sources of its



contamination include local municipal and industrial discharges



as well as its tributary system.  Detailed analysis of the conditions



and trends in water quality within the river are impossible because



of the limited amounts of data available.






The Tributary System of the Saginaw River



     a)  Shiawassee River



     The Shiawassee is 100 miles long and drains an area of



1200 square miles.  Fourteen municipal and institutional waste-



water treatment facilities and five major industries discharge



into the river.  Water quality from the mouth of the Shiawassee



to Corunna, located about half way upstream, is poor.  Excessive



mutrient concentrations exist in the entire lower 50% of the river.



Within this region, six reaches of substandard water quality have



been identified by the WRC  (1971) with regard to other water-



quality parameters.  Three of the six are degraded by inadequately



treated sewage  (efforts are being made to alleviate this problem).



Dissolved oxygen depressions and high coliform densities are



also characteristic of these areas.  Water quality in the upper



portions of the basin Is generally improved.  However, as a result

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                               43
of municipal discharges,  five mainstream reaches and two
tributary reaches have substandard quality.

    b)  Tittabawassee River
     The Tittabawassee Basin is approximately 2,620 square miles
in area and receives drainage from the Tobacco, Salt, Chippewa,
and Pine Rivers.  Most of the basin is sparsely populated, although
a large industrial center has developed as a result of underground
salt deposits.  Water quality between Midland and the Saginaw
River is very poor.  Four reaches of exceptionally substandard
water exist in this area according to the WRC  (1971) .  Three are
a result of inadequate municipal sewage treatment and exhibit
high coliform and nutrient levels and depressed dissolved oxygen
content.  The most severe drop in water quality occurs below
Midland where the   ver receives discharges from the municipal
wastewater treatment plant and the Dow Chemical Company.  The
river also experiences increased heat content; lowered D.O.;
and elevated levels of suspended and dissolved solids, conductivity,
temperature, pH; and taste and odor producing  substances.  On
isolated occasions excessive amounts of toxic materials have
occurred due to lapse in treatment operations.  High fish mortalities
were also noted.
     The principal water-quality problem of the Tittabawassee
is the high dissolved solids content, particularly  chlorides.
The Tittabawassee constitutes the major source of chlorides
within the entire Michigan basin to Lake Huron.  It is the major
chloride polluter of the Saginaw River and Bay.

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                               44
     The Pine River tributary, below the Alma-St. Louis area,



is substandard in quality (WRC, 1971).   It receives discharges



from two municipal treatment plants and local petroleum and



chemical industries.  Chlorides increase fourteenfold below this



area with lesser increases of nutrients, toxics, and suspended



solids.  Dissolved oxygen levels and oil discharges also result



in substandard quality.



     The Chippewa River has one reach of substandard quality,



receiving wastes from a municipal treatment plant and an industrial



discharge.





    c)  The Flint River



     The Flint River Basin has a drainage area of 1,350 square



miles and receives tributary water from North Branch, South Branch,



Farmers Creek, and Mistequay Creek.  There are seven municipal and



institutional wastewater discharges to the river, plus nine major



industrial dischargers.  The most serious breach in water quality



occurs below the City of Flint according to the Michigan WRC.



The Flint wastewater treatment plant contributes heavily to the



river's high organic content and high nutrient levels.  The result



is depressed D.O. concentrations and excessive algae



and aquatic weed growths.  Above the treatment plant the river



is degraded by storm water overflows, tributary waste loads, and



poorly treated sewage discharges.  Upstream from Flint the water



quality is generally good except for one lapse in which a municipal



discharge is located.  Efforts are being made to improve the dis-



charge characteristics of most municipal and industrial waste-



water discharges.  Although the Flint River accounts for only 25%

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                             45
of the Saginaw River flow, it contributes over 40% of the annual



phorphorous loading.





    d)  The Cass River



     The Cass River basin encompasses 931 square miles in six



counties.  It receives discharge from six municipal treatment



plants and several industries, including a sugar company and a



milk processing company.  Upstream reaches of the river exhibit



good D.O. and BOD characteristics.  The D.O. levels are depressed



and BOD levels elevated, however, below population and industrial



centers.  The problem is severe during the summer periods of low



flow and high temperatures.  As a result of these centers,



nutrient enrichment is high in the lower stream.  Total and



fecal coliforms are also at very high concentrations.






Au Gres River



     The Au Gres River has a drainage area of approximately



420 square miles and a gross estimated average flow of 250 cfs.



One municipal lagoon and one industry discharge into this river.



Water quality is generally good throughout the river except for



localized bacteriological problems.  One reach of the Au Gres'



high water quality is breached by the sewage discharges.  High



coliform and nutrient levels are present there.  Chloride levels



average about 25-35 mg/1 as N of organic ntirogen; .02 mg/1 as P of



dissolved P; and .07 mg/1 as P of total phosphorous  (see Table 2).





Rifle River



     The Rifle River drains an area of 387 square miles and has



a gross average flow of approximately 350 cfs.  It receives dis-




charges from one industry and one municipal plant.  Water

-------
                             46
quality is generally very good throughout the basin.  Chloride
and nutrient concentrations are generally very low.  A slight
seasonal increase in nitrogen levels  (from December to March)
has been noted at the river mouth.  Good D.O. and BOD character-
istics are exhibited throughout the river.  Only one localized
reach of substandard water quality exists (WRC, 1971) .  This oc-
curs below the two discharges.  Slight D.O.  depressions and high
nutrient and coliform concentrations are noted there at times.
     Representative nutrient concentrations at the mouth are
.02 mg/1 as P of dissolved phosphorous; .09 mg/1 as P of total
phosphorous; .15 mg/1 as N of nitrate; .06 mg/1 as N of ammonia;
and .4 mg/1 as N of organic nitrogen.  Chloride concentrations
averaged 17 mg/1 (EPA, STORET).

Tawas River
     The Tawas River has a small drainage basin of approximately
115 square miles.  It receives discharges from one municipal
treatment plant.  Water quality is generally good with the excep-
tion of two localized areas.  One is, as expected, near the munici-
pal discharge.  The other occurs at the mouth of the river where high
coliform densities are found from yet unidentified origin.  In
general, the D.O. and BOD characteristics are good and nutrient
concentrations fair.
     Representative nutrient concentrations  at the mouth might
be .2 mg/1 as P of phosphorous,  .2 mg/1 as N of nitrate,  and .3 mg/1
as N of ammonia.  Chloride concentrations average 10 mg/1.

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                             47
Pine River



     The Pine River collects drainage from the North, Middle, and



South Branch Rivers as well as other minor tributaries, combining



to a total drainage area of 99 square miles.  Only one municipal



wastewater treatment plant discharges into this river.  Water



quality in the Pine River is fair.  Dissolved oxygen concentrations



are high but BOD loadings indicate moderate organic loading to



the stream.  Elevated chloride concentrations have been reported.



A typical chloride level might be 60-100 mg/1.  The waters are



also considered to have nutrient enrichment.  Total phosphorous



concentrations often average over .4 mg/1 as P.  Nitrogen levels



generally are around 2 mg/1 as N, and nutrient concentrations appear



to have improved in recent years.  Total and fecal colifonti



densities in the river are moderate to high.






Kawkawlin River



     The Kawkawlin River basin drains approximately 224 square



miles of land and receives a discharge from one municipal treat-



ment plant.  Coliform concentrations are low upstream but increase



near the river mouth.  BOD levels indicate organic enrichment



throughout the river; however, D.O. levels are generally good.



Chloride concentrations are moderate but sometimes problematic.



Nutrient levels are not troublesome.  Flow reversal is similar to



that observed in the Saginaw River



     Typical concentrations at the river mouth are .06 mg/1 dis-



solved phosphorous as P, .1 mg/1 total phosphorous as P, 1.2 mg/1



nitrate as N, .17 mg/1 ammonia as N, .9 mg/1 organic nitrogen



as N and 70 mg/1 of chlorides (see Table 2).

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                             48
Sebewaing River



     The Sebewaing River has a drainage basin of 110 square miles.



Water quality is generally good in its upper stretches but poor



in its lower reaches.  BOD and D.O. concentrations indicate clean



water conditions upstream but organic enrichment and D.O. depres-



sion exist at the river mouth.  High total and fecal coliform



densities are noted throughout the river.  Nutrient concentrations



increase downstream but are not considered excessive.  Chlorides



are moderately high in the lower river, especially from August to



September.



     Typical concentrations at the river mouth are:  .2 mg/1 total



phosphorous as P, 2 mg/1 N03, .3 mg/1 ammonia as N, 1 mg/1 organic



nitrogen as N, and 60 mg/1 chlorides.





Other Contaminant Sources



     Besides the tributary sources already mentioned, there



exist several other minor tributaries on which little or no



data is available.  These include Silver Creek, Saganing River,



Pinconning River, Quinacassee River, Squaw Creek, Wiscoggin Drain,



Pigeon River, and Pinnebog River.  Their total output is considered



to be very inconsequential.



     There are no direct municipal discharges to the Saginaw Bay



and only a few industrial discharges.  These include power plant



cooling waters near the Saginaw River and at Quinacassee, and dairy



and sugar companies near Sebewaing.  All exert definite localized



effects on the bay.

-------
           V.  Physical and Chemical Considerations






     The physical and chemical parameters that have been measured




in Saginaw Bay are dealt with individually in Section V.  First^




a short general description of the parameter and its importance



is presented followed by a description of the existing and historical



conditions of the parameter in the bay.  Spatial and temporal




trends have been noted when observable and available, and are




presented on figures 10-18 and Tables 3 and 4.  It should be noted



here, first, however, that all trends and conclusions drawn are




subject to error as a result of the limited amounts of sampling




data.



     The majority of the conclusions drawn in the following section




were derived from the six principal sources of data listed below.



     1.  Beeton, A. M.; Smith, S. H.; and Hooper, F. H.  "Physical




         Limnology of Saginaw Bay,"  Great Lakes Fisheries Commis-




         sion Tech. Rep. #12, 1967.  A 1956 study of over 50 sta-



         tions in Saginaw Bay from June-October.  This is the only




         good, comprehensive study.  It included measurements of



         temperature, dissolved oxygen, calcium, magnesium, potassium,



         sodium, phosphorous, sulfate, alkalinity, specific conductance,



         and wind conditions.  The survey did not measure any forms




         of nitrogen, differentiate the forms of phorphorous, or




         make sufficient subsurface measurements.






     2.  Michigan Stream Control Commission,  "Saginaw Valley Re-




         port," May 1937.  A 1935-36 survey of  the bay which




         included measurements of hardness, alkalinity, turbidity,




         and chloride.  The chloride information was only  from

-------
                                                              JUNE  7
                                             Temperature °C
                                                                           OCTOBER  30
Figure  10.     Surface  temperatures  (eQ of Sagirmv Bay during synoptic cruises on June 7, August 10, and October
                 30, 1955.
Source:  Beeton,  et al., 1967.

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                                                                                 Calcium
                                                                                 Conductivity
            uistribution of sodium, calcium and sulfate (pprn).  and conductivity (tmlios at 18 ° C) in Saginaw Bay.
Figure  11    source: Beeton et  al.,  1967

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                                                                         Magnesium
                                                                          Alkalinity
      Distribution of potassium and magnesium (ppm), phosphorus (ppb), and alkalinity (pprn CaCOj) in Si
      Biy.Ji'-r.s 7, 1956.
Figure  12sotirce:  Beetrin et al.,  1967

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                                                   JUNE 21-22
                                        Chloride
\
                                                                     AUGUST 24-25
      ^Distribution of cMoriie (p?:n) jur.o 21-22, J^y 20-21, and Auy^t 24-25.
  Figure  13 source:  Beeton et al., 1967

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-------
$

-------
                                                       Calcium
                                                           Conductivity
Di!tr,,OT o« — — - ->« -» ^ '°™ "mte
October 30. 1956.

            Figure  16  source: Beaton at al.,1^
                                                                    In S

-------
                ^ ~
  July and August 19&6
                           CATURATIOH3 IH


                               SCALE  IH UlLCS
Prciiminciry  Draft, "SsfjlnrVn Bay and Southern
Lake Huron Trihutariea - ?iichic«in» Water  Quality
Data. 1965 Survey."  ^.iPCA.  jTsn-iry 10?^.

-------
                            58
            Mean Botton D.O". saturation levels
               July arid Rugust 196&
Figure 17  Source:
            Prcliir.inary Draft,  "Ussin-^v Bay and Southern.
            Lake Huron Vxuhutarics - Michican, Uatcr Quality
            Data,. .1965 Surrey."  FW?CA.  January .inGn

-------
                                           59
                 A\eraje  chemical  ciuiracterisuco oi v,atLr sari.yleb taut-it
                         (inside  line A-B, Fig. 1),  OL  Saginav.' Bay in 1956
ir.r.er area
Cations
Dnce Total
Calcium Magnesium Potassium Sockuru cations
(ppm) (ppm) (ppm) (pom) (epm)
June 7 55 11.2 3.6 15.8 4.44
June 22 - - - - -
Aug. 10 45 10.6 3.0 16.2 3.90
Aug. 25 - - - -
Oct. 30 39 9.4 2.0 11.6 3.27
Average 46 10.4 2.9 14.5 3.87
Average 2.31 0.86 0.07 0.63 3.87
expressed
as epm
World 1.49 0.42 0.08 0.36 2.35
average
freshwater
as epm2
1 Determined from total alkalinity measurements.
2Gorham, 1957.
Average chemical characteristics of
- Anions

Bicarbonate * Chloride Phosphorus SuLfate
(ppm) (pp™) (Ppm) (pom)
155 - 0.045 29
57.5
139 - 0.037 22
61.4
135 - 0.042 16
143 59.5 0.041 22
2.34 1.68 - Q.4fr


1.71 0.23 - 0.37





T
water samples taken in the outer area

Specific
conducts;
(unihos lo
553
_
463
_
391
469
_


_






(between lines A-B and E-F, Fig. 1), of Saginaw Bay in 1956
Cations
Date Total
Calcium Magnesium Potassium Sodium cations
(ppm) (ppm) (ppm) (ppm) {epm)
June 7 31 8.1 1.5 4.3 2.44
June 22 - - - _
Aug. 10 29 7.5 1.2 3.6 2.25
Aug. 25 - - _
Oct. 30 27 7.9 1.0 2.9 2.15
Average 29 7.8 1.2 3.6 2.28
Average 1.45 0.64 0.03 0.16 2.28
expressed
as epm
World 1.49 0.42 0.08 0.36 2.35
average
freshwater
as cpm2 Table 3 source
Anions
Bicarbonate1 Chloride Phosphorus Sulfate
(ppm) (ppm) (pom) (ppm)
117 - 0.013 12
13.6
123 - 0.024 12
8.4 _
113 - 0.016 10
118 11.0 0.018 11
1.93 0.31 - 0.23


1.71 0.23 " - 0.37


: Beeton etal., 1967

Specific
conducta
fcmihos 18
270
__
253
_
237
253







'Determined from total alkalinity measurements.
2Gorham, 1P57.

-------
Table 4   source: GLRD Univ.  of Michigan 1973
TABLK 12.
ph.itc. Data
Depths

All

Surface
a in
3-22 m
32-30 m


All '
Surface
3 m
3-22 m
32-80 m
Lake Huron dissolved oxygen, silica, nltrato nitrogen,-., ammonia nitrogen, soluble reactive phosphate nnd participate plios-
for each parameter aro given as the moan ± one standard deviation followed by the number of observations In parenthesis.
Dissolved oxygen, ppm- SiOj, ppm

10.7 ± 0.79 (23)

10.1 ± 0.37 (G)
10.2 ± 0.49 (4)
11.0 ± 0.07 (3)
11.5 ± 0.67 (5)


' 10.G ±1.0 (24)
9.51 ±0.27 (8)
0.00 (1)
10.8 ±0.73 (10)
11.8 ±0.20 (5)

1.29 t 0.33 ^21)

1.07. ± 0.15 (7)
0.94 (1)
1.20 ± 0.13 (8)
1.80 ± 0.16 (5)


1.15 ± 0.42 (23)'
0.81 ± 0.15 (8)
0.73 (1)
1.15 + 0.23 (9)
1.78 ± 0.19 (5)
,';..! NOj-N,. ppb
' 1 ' .
'•' i 145

. .; 139
. J111
...i' 147
. .,159
M V
Vi1'1 '
> ! 159
i/,141
(..' 146
,' '159
:190
Zone I
± 30' (21)
'*. -
± 31' (7)
• •• (1)
± 20 (8)
±33 (5)
1
'Zone 11
± 35 (23)
± 24 (8)
•  . t
,',:.,i46
v;''13G
.'!! . 123
154

± 3GT (18)
± 16 (6)
± 48 (6)
Zone IV
± 27 (16)
±85 (5)
. (1)
± 23 (10)

2!}.0
20.0
33

', . 21-4
• 21.3
22.0
21.4

± 9.2
± 3.7
±11


(20)

(7)
ID
(7)
(5) .


(20)
(6)
(1)
(0)
(4)
Bav
(16)
(5)
(6)

±7.6 (12)
±9.0

±7.4

(4)
(1)
(7)

Sol. P0<( ppb

2.7 ±

2.5 ±
1.5
3.8 ±
1.0


2.7 ±
2.4 ±
1
2.7 +
3.2 ±

6.3 ±
0.6 ±
4.0 ±
•
3.3 ±
4.2

2.4


3.2 (8)

1.7 (3)
(D
5.4 (3)
(1)


1.4 (16)
0.78 (8)


2.3 (3)
1.6 (5)

0.5 (12)
6.9 (G)
3.8 (G)

1.3 (2)
(1)


(D

Part. PO<(

23 + 12

13 ± 0.78
28
21 + 12
41


22 ± 2G
10 ± 23
17
33 ± 22
11 ± 14

34 ± 14
37 ± 19
33 "*" 11
30 ± 11

12 ± 7.6
12 ± 5.4


12 ± 9.0

ppb

(C)

(2)
(1)
(2)
(1)


(22)
(7)
(1)
(10)
(4)

(15)
(G)
(0

(13)
(5)

(S)

         \
                                                                                       r


                                                                                       w
                                                                                       o
                                                                                       X,
                                                                                                        cr>
                                                                                                        o

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                               61
         surface samples but otherwise was complete spatially.



         All other measurements came primarily from shore area



         stations.






     3.  Raw data from a 1966 survey by the U.S. Lake Survey   "•-



         Center.  Included only 4 stations, all in the outer



         reaches of the bay.






     4.  Schelske, C.L. and Roth, J.C.  "Limnological survey



         of Lake Huron," GLRD University of Michigan, 1973,



         Pub #17.  Data from a July 1970 survey on Lake Huron



         that included 6 stations in Saginaw Bay.  Only average



         values were available for parameters measured on this



         survey.






     5.  Limited amounts of data from cruises carried out by the



         Canadian Center for Inland Waters.






     6.  Raw information from the Michigan Water Quality Municipal



         Water Intake data:  "Water Resource Uses,"  Michigan WRC,



         1967.





Alkalinity



General Considerations




     Alkalinity is not a specific substance but rather a measure of



a waters ability to neutralize acids and is expressed in terms of



an equivalent amount of calcium carbonate.  It results from the



combined effects of several substances and conditions.  In natural

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                               62
 waters it is due primarily to the salts of weak acids, although
 weak and strong bases may also contribute.  Bicarbonates, carbon-
 ates, and hydroxides constitute the major sources of alkalinity
 since they leach heavily into waters through the action of carbon
 dioxide on soils and rocks.  Borates, silicates, phosphates, and
 organic substances also contribute, but to a lesser extent.
      Alkalinity is also an indirect measure of a water's buffer
 capacity, its ability to resist change in pH due to the addition
 of acids or bases.  This buffering ability is important to
 prevent changes in pH that might prove harmful to biotic communi-
 ties.  Most organisms are acclimated to a specific pH range and,
 if exposed to conditions outside of this range, they can experience
 deleterious effects.  Diurnal photosynthetic activity can cause
 fluctuations in pH.  These changes are controlled by the alkalinity
 and, hence, are usually small enough and temporary so as not to cause
 harm.
      In general it can be stated that alkalinity has not
been shown as yet to be lethal to fish if the pH is kept below 9.
 Other effects on fish have only been noted at low alkalinity and
 pH conditions.  Carbonate alkalinity seems to have no harmful effect
 on plankton or other aquatic life.  It has been theorized that
 high alkalinity is antagonistic towards toxicity of copper sulfate
 to fish.

 Observed Conditions
      The alkalinities measuring in the bay by Beeton et al. (1967)f

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                              63
during surveys from June 7 to October 30, 1966 show values
ranging from approximately 90 to 150 ppm as CaCO_ (see figures
12 and 14).  These alkalinities offer a sufficient buffer capa-
city to support a diverse aquatic community, given other favorable
conditions.  Spatially, the alkalinities tend to have higher values
at the  south and southeastern portions of the bay, with maximal
values occurring at the mouth of the Saginaw River.  Lowest alka-
linities were observed near the mouth of the bay.  The distribution
is a result of inflow from the Saginaw River, where concentrations

range from 123 to 187 ppm  (as measured by the Dow Chemical Company
in spring and summer'of 1956).  These high alkalinity waters increase
the natural background alkalinity of the Lake Huron waters (below
90 ppm according to the U.S. Lake Survey Center's Lake Huron Limno-
logical Data).  The higher alkalinities tend to follow the north-
easterly flow of the Saginaw River water within the bay.  This trend
does not always, however, extend pronouncedly very far beyond the
mouth of the river due to the variable circulation in the bay.  Dis-
tribution is regulated thereafter by the diluting effect of the
Lake Huron waters.  In general, alkalinity concentrations averaged
between 110 and 125 ppm in the inner bay and approximately 100 ppm
in the outer bay.  The values in the outer bay are confirmed by data
from the U.S. Lake Survey and Canadian Center for Inland Waters.
     Temporally it appears that the alkalinity has increased slightly
in the last 30 years.  According to the Saginaw Valley Report of
1937 (Michigan Stream Control Commission), values for alkalinity
at 11 stations along the coastal regions of the bay  (excluding the

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                              64
most southerly end) varied from 82 to 124 ppm with the average



value in the low 90's.  The alkalinities at the mouth of the



Saginaw River ranged from 95 to 185 ppm.  Although this data is



lacking in both station location and numbers, it does seem to indi-



cate that the alkalinities may have increased as much as 10 to



15 ppm in the last 30 years.



     The Stream Control Commission's data also reflects the di-



luting effect of the Lake Huron waters although any further cir-



culation pattern from the alkalinities cannot be ascertained



because of the location of the sampling stations (now relocated



within the central portions of the bay) and their scarcity.



     Locally within the bay there appears to be no severe vertical



distribution of alkalinity.  The Lake Survey data, however, indi-



cates alkalinities of 1 to 3 ppm higher in the hypolimneon during



summer stratification.  This may be coincidental, a methodological



error, or it may have a limnological basis.  It is possible that



the photosynthetic activity in the epilimneon produces CaCO_ pre-



cipitation through uptake of C0_ and a shift in carbonate equili-



brium.  The precipitated CaCO., settles into the hypolimneon where



it meets aggressive CC>2 concentrations as a result of bacterial



decomposition.  The end result is resoluablization of the CaCO,



and an increase in alkalinity.  Although this phenomenon can occur,



the Saginaw Bay data is insufficient to positively document it.







Biochemical Oxygen Demand  (BOD)



     Biochemical oxygen demand is usually defined as the amount

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                              65
of oxygen required by bacteria to stabilize or oxidize decomposable



organic matter under aerobic conditions.  High BOD's are undesir-



able because of their resulting oxygen depletion and their dele-



terious effect on fish and other aquatic life.  A water's ability



to satisfy a BOD without harmful effects is dependent on the BOD



and oxygen levels, mixing characteristics, surface to volume ratio,



temperature, photoproductivity, as well as many other parameters.



     Unfortunately no significant BOD data was found concerning



the Saginaw Bay.  The effects of its exertion will, however, be



discussed in the section dealing with dissolved oxygen.








Calcium



General Considerations



     The ions of calcium salts are among the most common constit-



uents found in natural waters.  Calcium is the principal cation



imparting hardness into most surface waters, often to the degree



that they are inadequate for municipal or industrial use.  Sources



of calcium include natural leaching from soils and rocks and dis-



charges from municipal and industrial wastes.



     Calcium has not been shown to be harmful to aquatic life at



reasonable levels.  Fish have survived in synthetic concentrations



of Ca over 2500 ppm.  Calcium has further shown to be antagonistic



towards the toxicity of lead and zinc.



     No U.S. Public Health drinking water standards or Michigan




water quality standards have been set regarding calcium, although




the World Health Organization  (WHO) recommends 75 mg/1 as a limit  and

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                              66
200 mg/1 as an acceptable limit for drinking water.







Observed conditions



     In the 1956 survey (Beeton et al., 1967) calcium values



were found to range from 25 to 80 ppm (see figures  11,  15,  and



16).  On the June  7 survey, concentrations were  found to  be



heaviest along the south and southeastern portions of the bay.



Nearing the outer bay, concentrations approached the normal Lake



Huron background values of 20 ppm.  This again indicates the influ-



ence of the high solids content of the Saginaw River and diluting



waters of Lake Huron.  The October 30 survey demonstrated high



concentrations (40-50 ppm) at the mouth of the Saginaw River



decreasing to lesser values in the outer bay (20-30 ppm).  A



distinctive counterclockwise circulation of Saginaw River waters



was not noted as before due to a probable difference in wind condi-



tions.  Overall concentrations appeared to be greatest in the



June survey (max 80 ppm) and least in the October survey  (max



46 ppm).  This may be a result of differences in river flow/ higher



in the spring and lower in the fall but may also be coincidental.



     The Lake Survey data for the outerbay agrees with the  1956



survey showing chloride values from 15 to 32 ppm.  The Michigan



Stream Control Commission study of 1936 did not include calcium



sampling.  It did include hardness, data which is closely related



to calcium.  It indicated a pollutional source from Saginaw River



with a diluting effect from the Lake Huron waters.  Hardness con-



centrations ranged from 358 ppm as CaCO., right at the Saginaw

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                              67
River mouth to 85 ppm in the outerbay.
      In general,  the calcium and  hardness  levels  in  the bay  are
excessive but not troublesome.  They may at times violate WHO
drinking water recommendations  (75 mg/1 Ca) but always fall below
the acceptable limit.  Bay water may need to be softened for
specific industrial  and municipal uses.

Chlorides
General Considerations
     The chloride ion is a common constituent of most natural
waters and has high  solubility characteristics.  The chloride
ion is involved in very few natural removal reactions.  It is,
therefore, considered to be a conservative ion and is often used
as tracer in pollutional and flow studies.  Sources for chlorides
include mineral solution, agricultural runoff, ground water, and
industrial and municipal discharges.  Chloride levels of as low
as 100 mg/1 may impart salty taste, although the usual  taste
threshhold is 400 mg/1.  Higher levels of chloride increase
oxidative corrosion rates.
     Effects of chloride on aquatic life vary.  Trout appear to
be the most sensitive fish with reported harmful effects at 400
mg/1.   Effects in general, however, often depend on the presence
and amounts of other salts.  Changes in natural chlorinity can
exert harmful effects because of alterations in osmotic conditions,
     The U.S.  Public Health Service has set 250 mg/1 Cl as a

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                              68
recommended upper limit to. chloride concentrations for drinking
water.

Observed Conditions
     The Michigan Stream Control Commission carried out ex-
tensive chloride surveys of Saginaw Bay in 1935 and 1936.  Fifty
surveys were completed in that time.  They reported concentrations
ranging from as high as 350 mg/1 at the mouth of the Saginaw River
to as low as 3 mg/1 in the open bay.  In general, concentrations
were highest in the vicinity of the Saginaw River ranging from
50 to 300 mg/1.  No consistent distribution of chloride concen-
trations was noted.  Higher concentrations did/ however, tend to
originate from the river and then follow the prevailing wind con-
ditions.  Because of changing wind conditions and natural bay
currents, the degree of mixing and concentrations distribution at
times seemed random.  Average concentrations in the inner bay
appeared to range from approximately 25 to 40 mg/1.  Limited data
was taken on the outer bay.  Concentrations there averaged below
10 mg/1.
     In the 1956 surveys  (Beeton  et al.), chloride concentrations
ranged from greater than 280 mg/1 at the mouth of the Saginaw
River to 7 mg/1 in the outermost bay  (see figure  13).  Chloride
levels averaged 59.5 mg/1 in the innerbay and 11.0 mg/1  in the
outer bay.  High concentrations originated from the Saginaw River
and appeared to flow counterclockwise around the  bay.  Higher con-
centrations were, however, also noted west of the river  in two

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                              69
surveys.  The spatial distribution of concentrations is heavily
dependent on wind conditions.   The prevailing westerly wind condi-
tions promote a counter clockwise circulation.
     Concentrations in the 1956 survey are generally larger than
those found in the 1936 survey by as much as 20 mg/1 in the inner
bay and 5 mg/1 in the outer bay.  Precise comparisons are difficult
because average concentrations were not available for the 1936
study.
     The 1966 Lake Survey study of the outer bay reported concen-
trations from 3.4 to 20.4 mg/1.  Concentrations varied by as much
as 15 mg/1 at specific stations.  Sample locations were insufficient
in number to observe any spatial distributions.  Average concen-
trations ranged from 4 to 7 mg/1.  No additional trends could be
observed.
     The July 1970 survey by The University of Michigan Great Lakes
Research Division  (GLRD) reported an average chloride concentration
of 10.6 mg/1.  The survey emphasized outerbay sampling and, therefore,
did not reflect the overall bay average.  No distribution data was
available.
     Michigan municipal intake water quality data was limited to
just a  few sampling points located within shore proximity.  These
data agreed with the previously reported data; observed concentra-
tions ranged from  11 to 85 mg/1 chlorides.
     The most extensive chloride surveys of the bay have been
carried out periodically by Dow Chemical Company, Midland, Michigan,
since 1935.  Limited amounts of the data were available in concentra-
tion color-coded maps.  As previously demonstrated, concentration

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                               70
 levels of chlorides varied widely in the bay with space  and time.



 Heavy concentrations were always noted in the vicinity of  the



 Saginaw River,  and low concentrations observed in the  outer bay.



 The distribution beyond this was heavily controlled by the prevail-



 ing winds.   The predominant westerly winds resulted in heavier



 concentrations  on the eastern portions  of the inner bay, while



 south and easterly winds caused a clockwise concentration  distribution.



 Changes in  overall chloride levels with time were not  easily



 observed because average concentrations were not  available.  From



 just gross  observation it appears the levels have increased just



 slightly since  the 1930's,  although slight improvement has been



 noted in the 1960's.




      In general,  the  Saginaw Bay, is genuinely contaminated by



 chlorides from  the Saginaw River.   Levels have not reached the



 point at which  they have proven to be toxic or offensive and are



 not  in violation of any standards.   Subtle effects may, however,



 have been exerted due  to their influence.   Distribution of chlor-



 ides is  highly  variable depending mostly  on wind  conditions.





 Conductivity



 General  considerations




      Conductivity is a  measure of  a solution's  ability to  conduct



 an electric  current.   It is  reported  as the  specific electrical



 conductance, the  reciprocal  of  the  resistance  in  ohms of a one



 centimeter column of solution  at  a  specified  temperature.  Pure



water is itself an  insulator.   It  is  the  presence  of ions  in



 solution that gives water its  good  conductivity characteristics.



The higher the ion content or  salinity, the greater is the con-

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                                 71
ductivity.  Conductivity  is, therefore,  an  indirect measure  of



salinity.  This characteristic  is important because all  aquatic



organisms have adapted themselves to specific  conditions of  sal-



inity which exert a specific osmotic pressure.  They  can tolerate



small changes in the relative amounts of salts but not the overall



concentration.  Large changes in salinity will effect osmotic



conditions and can result in ill effects for aquatic  fauna.





Observed Conditions



     In the 1956 synoptic surveys (Beeton et al., 1967)  conduc-



tivity ranged from a high of 825 ymhos in June near the  mouth of



Saginaw River to less than 200  ymhos at  the mouth of  the bay, all



taken at 18° C.  (See figures 11, 15, and 16).  Conductivity was



generally higher on the eastern side of  the bay with  a decreasing



gradient towards Lake Huron proper.  The average inner bay



conductance was 553 ymhos, decreasing to a  270 ymhos  average for



the middle and outer bay.  The August 10 and October  30  surveys



also showed higher conductivities in the southern end of the bay



decreasing outward.  On these dates, the respective average  specific



conductance was 463 ymhos and 391 ymhos  for the inner bay, and



253 ymhos and 237 ymhos for the middle and outer bay.  The latter two



surveys did not show a significant spatial pattern of conductivities other



than that already noted.   Wind conditions probably caused a mixing



of the surface waters (from which the samples were taken), masking



any general circulation pattern.



     In the 1956 surveys,  higher conductivities were noted in the



June 7 survey,  decreasing in August and again decreasing in October.

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                                72
 This  trend  similarly  appears with  regard  to  the majority of  the



 ionic parameters  and  again  is  attributed  to  variability in stream



 flow  and  dissolved  solids loading.



      Conductivity measurements were  not taken  in  the  1935 Stream



 Control Commission  Survey,  so  no trends can  be documented.   The



 1966  Lake Survey  data reaffirms the  specific conductivities  found



 in  the very outer bay by Beeton et al.  (1967).  Their data demonstrates



 an  average  of  about 200 ymhos.  A  July 1970  survey by the Great



 Lakes Research Division of  The University of Michigan found  an



 average conductivity  of 247 ymhos  at 25°  C for the middle and



 outer bay.   This  Compares with the average of  270 umhos and  253



 ymhos (at 18°  C)  found by Beeton in  June  and August of 1956.  Con-



 sidering  this  limited data  alone,  the specific conductivity  of the



 bay has not increased in the last  15 years.






 Dissolved Oxygen  (D.O.)



 General Considerations



      All  living organisms are  dependent on oxygen in  one form



 or  another  to  maintain their metabolic processes.  The majority



 of  processes in a "healthy" lake are aerobic and require free



 dissolved oxygen.   For this reason the measurement of dissolved



 oxygen has  become a standard for assessing the conditions of



 natural waters.   Low  levels of  oxygen can result in the death of



 fish  and other  aquatic biota.   If  the level  has not reached  this



 critical point, harmful effects may  still  be manifested by dis-



 ruption of  the  growth, development,  and strength characteristics



 of the organisms  or their eggs  and young.  Different  organisms have



various tolerances  to  low levels of  dissolved oxygens,  Michigan

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                                 73
has set the following water quality standard to preserve aquatic
life.   For intolerant warmwater fish, average daily D.O. value
should not be less than 5 nor should any single value be below
4 rag/1; for intolerant coldwater fish not less than 6 mg/1 at
any time; and for tolerant warmwater species an average not less
than 4 nor any value less than 3 ing/1.
     Oxygen levels are regulated by physical, chemcial, and
biological processes.  Oxygen enters into the water through two
avenues, photosynthetic activity and diffusion from the air.  It
is removed primarily through the respiration of bacteria in the
stabilization of organic matter (BOD), the respiration of other
animal and plant life^ and also the chemical oxidation of material
in the water.  The saturation or equilibrium concentration
of dissolved oxygen is regulated by atmospheric pressure, water
temperature, and salinity.  The saturation concentration
increases with the atmospheric partial pressure of 02 and decreases
with salinity and temperature.  Increases in temperature also
increase respiratory rates and, hence, indirectly lead to faster
oxygen depletion.
     In general, oxygen levels can vary widely both vertically
and horizontally depending on the physical, chemical, and biologi-
cal conditions.  It is, therefore, often used as a water quality
indicator.

Observed Conditions
     Beeton et al.  (1967) measured dissolved oxygen only in the
middle and outer zones of the bay during the ice-free months of

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                                  74
 1956.   They  found  oxygen  levels  to  vary with temperature as



 theory  would predict.   The  degree of  saturation increased with



 higher  wind  and mixing  conditions.  D.O. concentrations ranged



 from  6.3  to  11.7 ppm with an  average  concentration of approximately



 9 ppm.  Percent saturation  varied but rarely dropped below 90%.



 The lowest value of 66% was isolated.  It occurred in June in



 the middle bay area at  bottom depth.  Percent saturation values



 appeared  to  decrease slightly in the  fall, dropping a couple



 percentage points, despite  the decreasing temperature.  The



 probable  explanation is the fall die  off of phytoplankton and



 their subsequent stabilization by bacteria.  The lower waters in



 the very  outer bay demonstrated higher dissolved oxygen levels,



 than in the  inner bay.  An  influx of  the colder, oxygen-rich



 Lake Huron waters is the probable explanation.



     The  1966 Lake Survey data revealed D.O. levels parallel to



 those found  in Beeton's study.  Similar seasonal and spatial



 trends were measured.   Unfortunately  this data also pertained only



 to the outer bay.



     The only significant source of oxygen data for the inner bay



 is contained in a preliminary study by the Michigan Water Resources



Commission from a 1965 survey (see figures 17 and 18).  It documented



 near 100% saturation for all  surface  waters in the inner bay and



 93-100% saturation in the middle and  outer zones  (July and August



 1966) .  Bottom saturation levels averaged 95% in the outer bay



 and approximately 80% in the  inner bay.  The lowest point of



 saturation occurred opposite  Pt. Au Gres where saturation values

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                                 75
fell to 75%.
     A July  1970 survey of 6 stations in the bay by the Great
Lakes Research Division of The University of Michigan reported
near saturation concentrations of oxygen at all stations.  Satura-
tion levels did, however, decrease slightly with depth, dropping
to as low as 92% in near bottom samples.
     In general, it can be concluded that the BOD and sediment
demand of the bay have exerted slight effects on the oxygen con-
tent of the waters.  The reduction in D.O. has not yet, however,
reached the point at which it is harmful to aquatic organisms.
The surface D.O. concentrations have remained sufficiently high
to meet all Michigan water-quality standards, even for the fish
and wildlife classification of intolerant coldwater fish species
(76.0 mg/1).  The shallowness of the bay allows sufficient mixing
of the bay waters to keep the water column well oxygenated
during the ice-free months.  No data for D.O. conditions under
the winter ice cover was available.

Hydrogen Ion Activity
General Considerations
     The concentration of the hydrogen ion in a solution is
generally expressed in terms of the pH which is the negative
logarithm of the concentration.  The pH is a measure of the in-
tensity of the acid or alkaline conditions of a solution and is
a master control parameter that governs such phenomena as solubil-
ity, degree of dissociation, and acid base equilibrium.  It can
severely effect the toxicity of chemical species in the water as
well as the productivity and viability of aquatic organisms.

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                                  76
      The Michigan water quality standards for all uses generally



 require a pH of between 6.5 and 8.8 with an induced variation of



 no more than .5 units.






 Observed Conditions




      In the 1956 surveys of Saginaw Bay, Beeton et al.  (1967)



 found that the changes  in pll of the surface waters followed the



 same trends in all areas of the bay.   They found the pH to



 increase from 7.9-8.1 in June to a high of 8.4 in July and then



 to decrease to lower values in the fall.  They found similar



 fluctuations in the bottom shallow waters of the outer bay,  but



 no such trend in the deeper waters.   These fluctuations are



 possibly a manifestation of photosynthetic activity:   the  uptake



 of C02  increases the pH;  and then the fall die off is followed by



 a  production of C02 and drop in pH as the biomass is  stabilized.



      Beeton also found  lower pH's (7.6-8.0)  in the bottom  waters



 of the  outermost parts  of the bay.  They attributed this to  the



 influx  of Lake  Huron waters and their associated lower  pH.



      The 1966 Lake Survey data showed a pH range from 6.99  to



 8.48.   This  data demonstrated the same seasonal fluctuation  that



was  found by Beeton et  al.  as well  as the hypolimnic  influx  of



Lake  Huron waters.   The  pH values were of the  same range as  in



1956  and did not indicate  any significant change.



     A  1970  survey by Great Lakes Research Division of  The



University of Michigan  specified  an outer bay  average pH of  8.46.



This value appears  to be  elevated.   (Other values  measured for



Lake Huron proper were also  elevated  as  compared with a 1956



study of Allen  (1964).  The  GLRD  found average  pH  in  Lake Huron




of approximately  8.4 as opposed to Allen's value of 8.1.  This

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                                 77
indicates a possible methods error in the 1970 work or a less
likely general increase in pH of Lake Huron proper.
     No pH data was available from the 1936 Stream Control Com-
mission study.
     The pH's, in general, fell within a range tolerated by most
aquatic organisms and did not demonstrate any severe fluctuations.
They did not violate any drinking water or water-quality standards.
The pH is, therefore, considered not to be a problem parameter in
Saginaw Bay.

Magnesium
General Considerations
     Magnesium is commonly found in natural waters as a divalent
cation.  Magnesium is a very active chemical and is very rarely
found in the elemental form.  All magnesium salts, with the excep-
tion of the hydroxide at high pH's, are very soluable.  Magnesium
is a significant constituent of hardness and is found in most
natural waters.  Sources include dissolution from soils and rocks
(such as tolomite) and industrial and municipal discharges.
     Magnesium has been reported to be lethal to fish at concen-
trations as low as 476 ppm.  Low levels of magnesium below 100
ppm have shown no adverse effects towards aquatic life.

Observed Conditions
     Magnesium levels were found(Beeton et al., 1967) to range from
7 to 15 ppm in their 1956 survey  (see figures 12 and 14).  In
each of their surveys the magnesium levels were highest at the
south end of the bay near the mouth of the Saginaw River.  Beyond
this point the waters are increasingly diluted by the Lake Huron

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                                78
 waters  (magnesium  concentration of approximately  6 ppm).  Slightly



 higher  concentrations were  found on  the  southeastern bay as compared



 to  the  southwestern  portions.  The distribution,  however, was



 variable  again  probably  due to wind  conditions affecting the



 surface waters.



     The  1966 Lake Survey limnological data showed magnesium



 concentrations  from  6.3  ppm to 12.5  ppm  but demonstrated no



 obvious trend.  No magnesium data was available from the 1970



 or  1936 surveys.






 Nigrogen



 General Considerations



     Nitrogen is an  essential nutrient to all life processes.



 It  is a necessary  constituent of all proteins.  The aquatic



 chemistry of nitrogen is complex because of the varying valence



 states  and forms nitrogen can be found in.  Nitrogen occurs in



 natural waters  in  six major forms.   It can be incorporated into



 biomass of which the suspended portion is normall termed particu-



 late nitrogen.  In this  state the nitrogen usually has a valence



 of  3- and is incorporated into proteins.  Organic nitrogen is also



 found in  the soluble state  and is appropriately named.  The



 inorganic forms of nitrogen include  nitrate, nitrite, ammonia, and



 nitrogen  gas having valences of 5+,  3+,  3-, and 0 respectively.



 In nature, nitrogen is cycled through these various forms as plant



 and animal life carry out their metabolic processes.



     The  total concentration of nitrogen is significant when



 considering the trophic aspects of a lake, while  the specific




 forms are important in evaluating responses of various types of




organisms.  Inorganic nitrogen is utilized by phytoplankton (some

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                                 79
of which can fix atmospheric nitrogen) to synthesize biomass.



The organic nitrogen is further consumed by bacteria or other



heterotrophs and incorporated into more biomass or broken down



into the inorganic forms.



     Nitrogen enters the aquatic biosystem through nitrogen gas



fixation, industrial and municipal wastes, runoff of artificial



fertilizers and also the solublization of certain mineral deposits.



     Nitrogen levels are often critical in control of nuisance



algal growths.  Various authors have reported levels of inorganic



nitrogen above which excessive algal growth may occur.  This



level can vary, however, depending on the balance of other nutrients.



Sawyer  (1957) reported .3 mg/1 to be that level, with an inorganic



phosphorous concentration of .015 mg/1.  Ammonia and ammonium



salts have been shown to be toxic to aquatic life.  The degree



of toxicity is related to the pH which controls the dissociation



of ammonium hydroxide.  Higher pH's increase toxicity.






Observed Conditions



     Despite the considerable importance of nitrogen as a nutrient



contaminant to natural waters, very little nitrogen data has been



taken in Saginaw Bay.  Neither the 1956 or 1935 surveys of the



bay measured any forms of nitrogen.  The 1966 Lake Survey data



measured soluable nitrate at all stations, but information was



restricted to the outer bay.  Concentrations ranged from 0 to



3.9 mg/1, using an unspecified method of measurement.  Measureable



concentrations were reported only in the spring and early summer



outside of which all waters had concentrations below their de-



tection limits.  The lowest detectable amount of nitrate reported




was .3 mg/1.  No spatial trends were noted.

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                              80
     The  1970 Great Lakes Research Division survey noted an
average concentration of nitrate in Saginaw Bay to be .042 mg/1,
well below  the apparent detectable range of the Lake Survey's
methods (see Table 4).  The 1970 GLRD survey's average con-
centrations showed concentrations increasing with depth.  This may
be an effect of phytoplankton uptake in surface waters and the
subsequent breakdown and release in the deeper bottom waters.
Ammonia nitrogen was also measured in the 1970 survey.  The
average bay concentration was .0259 mg/1.  Ammonia demonstrated
concentrations  increasing with depth similar to nitrate.  The
average surface concentration was .020 mg/1 as compared with the
bottom concentrations of .033 mg/1.
     Very limited information from a 1971 survey by the Canadian
Center for Inland Waters indicated a maximum observed inorganic
nitrogen concentration of .777 mg/1 in the inner bay and a maxi-
mum concentration of .307 mg/1 in the outer bay.  No range or
average values were available, except for the areas near the mouth
of the bay where concentrations were approximately .2 mg/1.
     Although the overall data is insufficient to confirm any
definite trends,a few general speculations are possible.  First,
the nitrate concentrations are generally lower in Saginaw Bay
than in Lake Huron proper where the concentrations of nitrate
average about .150 mg/1 (GLRD 1970).  The bay average is .042 mg/1.
This is a consequence of algal uptake, accelerated as a result

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                              81
of the excessive nutrients available, particularly phosphorous.
Ammonia concentrations appeared to be somewhat higher in the
bay region (average .0259 mg/1) when compared with the uncontam-
inated open waters (average .0126 mg/1).  This again may be a
result of higher biologic activity.  The breakdown of proteins
within the water column and in the low oxygen-containing sediments
can release free ammonia.  The general low levels of total in-
organic nitrogen, at times below .050 mg/1, indicate a slight
possibility of nitrogen limitation.

Phosphorous
General Considerations
     Phosphorous, like nitrogen, is essential for all aquatic
life.  It is intimately involved in the energy storage and release
systems of all organisms.  Because of its role in natural and
cultural eutrophication, phosphorous has become one of the most
discussed chemicals in the aquatic environment.  Although total
agreement has not been reached concerning phosphorous' role, it
is accepted that large quantities of phosphorous must be available
to support algal blooms.
     Phosphorous occurs in natural waters as a result of leaching
from minerals and soils, agricultural drainage, municipal and
industrial discharges, and degradation and release from organic
matter.  Once in a water system, its removal is controlled by
associated adsorption and sedimentation processes, biological or

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                              82
 cultural removal of phosphorous containing biomass, and natural



 transfer due  to flushing.



      It is generally acknowledged that ortho-phosphate is the



 form  of phosphorous directly used by phytoplankton, although all



 forms of phosphorous represent potential sources of nutrients as



 a result of biodegradation and hydrolysis.  In water the various



 phosphorous forms are differentiated as soluable reactive phos-



 phorous, usually considered to be PO.; soluable organic phosphorous",



 and particulate phosphorous or that incorporated into biomass.



     Although excessive amounts of phosphorous can cause nuisance



 algal blooms  with associated odors and indirect detrimental



 effects on fish and other aquatic life, phosphates themselves do



 not exert any toxic effects.



     Studies  of the productivity of 17 Wisconsin Lakes suggest



 a concentration of .01 mg/1 of inorganic phosphorous as a maxi-



 mum value permissible without the danger of support of undesirable



 growths.  It  should be noted, however, that algal growth may be



 controlled by numerous other nutrient and physical conditions as



well.








Observed Conditions




     In the 1956 survey (Beeton et al.,  1967)  average  concentrations



of .041 mg/1  and .018 mg/1 total phosphorous were reported in



the inner, middle, and outer bays respectively.  In the inner



bay average concentrations were .045 mg/1 during the June 7 survey,

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                              83
 .037 mg/1 for the August 10 survey, and  .042 mg/1 in the October
 30 survey.  The respective outer bay average concentrations were
 .013 mg/1,  .024 mg/1, and .016 mg.l.  The spatial distribution
 of phosphorous was interesting because it did not follow the dis-
 tribution of the other contaminant ions  (see figures 12 and 14).
 Although concentrations were as usual high near the mouth of the
 Saginaw River (approximately .070 mg/1 in all the surveys) and
 low near the mouth Of the bay .010 mg/1,the remainder of the
 distribution was not as typical.  Phosphorous concentrations often
 appeared equally high on both the east and west sides of the inner
 bay.  Furthermore, a tongue of low phosphorous concentrations
 (.030 mg/1 or less) was noted extending into the center of the
 inner bay from the outer bay.  On the August 10 survey, high
 concentrations were found on the shore side areas of the outer
 bay increasing shoreward from .020 to .050 mg/1.  These spatial
 trends are somewhat contrary to the distribution of other ions.
 It may be a consequence of phosphorous runoff from land areas
 surrounding the bay and phosphorous inputs from the bay's other
 tributary streams.  Since a large portion of the land areas are
 agricultural, large amounts of nutrient runoff can be expected.
This runoff would not include as high a concentration of other
 ions (calcium,  magnesium, chloride, etc.) and/  hence, would impart
 little effect on the Saginaw River's induced distribution of the
 ion contaminants other than phosphorous.   It is unfortunate that
the 1956 survey did not include nitrogen measurements which might
have better verified this theory.

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                              84
     Lake Survey Center's 1966 survey reported outer bay ortho-



phosphorous concentrations of 0 to .4 mg/1.  Well over 80% of



the samples were reported to have had concentrations below their



detection limits.  The lowest reported concentration was .1 mg/1.



No spatial distribution was noted.  Seasonally, concentrations



appeared to be greater in the spring and fall approximately at



the times of turnover.  The data is, however, questioned since



the reported concentrations of .100 to .400 mg/1 are excessively



high when compared with values reported by others in the bay and



Lake Huron proper.



     The GLRD's July 1970 survey reported average concentrations



of .053 mg/1 soluable reactive phosphate and .034 mg/1 particulate



phosphate for the middle and outer bay (see Table 4).  Soluble



reactive phosphorous concentrations ranged from .0005 to .020 mg/1,



the higher concentrations in the inner bay.  Both parameters



appeared to decrease slightly with depth.



     A 1971 survey by the Canadian Center for Inland Waters



reported concentrations of total phosphorous averaging from .010



to .030 mg/1 in the middle and outer bays for the months April



through November.  The concentrations showed an increasing gradient




from Lake Huron to the southern end of the bay.   Soluble reactive



phosphorous was reported to range from .005 to .001 mg/1 with the




higher values also in the southern bay.



     In genera]/  the  phosphorous  levels as  reported  by the  above

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                              85
mentioned surveys are sufficient to support excessive algal
growths, given other conducive conditions.  No conclusions can
be drawn concerning the distribution of phosphorous within the
bay except that the highest concentrations were reported near
the Saginaw River outlet.  The data was insufficient to determine
any changes in overall concentrations with time.

Potassium
General Considerations
     Potassium is a highly active metal and reacts vigorously
with oxygen, hence, it is only found in the ionic or molecular
form in nature.  Its salts are highly soluble and it is quite
conservative in nature.  Sources for potassium include municipal
and industrial discharges, irrigation waters, and leachment from
soils and rocks.
     Potassium is a necessary nutrient for algal growth but has
never demonstrated to be a limiting factor in their natural growth.
Potassium has not been shown to be toxic to any life at levels
below 400 mg/1.

Observed Conditions
     The 1956 Beeton et al.  survey reported concentrations of
potassium from 1 to 6 mg/1 (see figures 12  and  14}.   Concentra-
tions for the inner bay were highest in the June 7 survey (average
3.6 mg/1) and lowest in the October 30 survey (average 2.0 mg/1).

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                              86
The total average for the inner bay was 2.9 mg/1 and 1.2 mg/1



for the outer bay.  Higher concentrations were generally found near



the southernmost end with the lowest levels at the mouth of the



bay.  The potassium distribution was found to parallel that of



phosphorous.  In both the August and October surveys small tongues



of waters with lower potassium concentrations were found in the



inner bay.  In addition, in the October survey, high concentrations



were found on the shoreward portions of the outerbay.  This informa-



tion reinforces the speculation that agricultural runoff can be



significant, since potash (K-0) is a major constituent of most



fertilizers.



     The 1966 Lake Survey Center data reports potassium concen-



trations in the outer bay of .1 to 1.5 mg/1.  No spatial or temporal



trends were observed in the 1966 data.  No additional sources




of data were available.



     The potassium concentrations were, overall, high in the



Saginaw Bay as compared with Lake Huron waters  (.6 to 1.3 mg/1;



Allen, 1964). Possible significant contaminant  sources besides the



Saginaw River include agricultural runoff from  all land-surround-




ing areas.








Silicon



General Considerations



     Silicon is the second most abundant element on  earth, repre-



senting 28% of the earth's crust.  It is, however, never found in

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                              87
the elemental form in nature but occurs as silica in sand or quartz
and silicates in feldspar, kalonite,and other minerals.  Silicon
usually occurs in natural waters as silicon dioxide.  It is associa-
ted with colloidal or suspended matter or incorporated into biomass.
Silicon is an essential nutrient used in structural tissues of
many algae, particularly the diatoms.

Observed Conditions
     Concentrations of silicon reported from the GLRD July 1970
survey averaged 1.06 ppm as silicon dioxide (see Table 4).  No
spatial distribution was noted.  A clear absence of surface sili-
con depletion indicates either high mixing conditions or more
probably the low diatom activity of the Saginaw Bay in the summer
months.
     The 1966 Lake Survey information documented silicon dioxide
concentrations ranging from .5 to 2.5 mg/1.  No spatial or temporal
relationships were observed.  No other silicon data was available.

Sodium
General Considerations
     Sodium is another active metal that does not occur free in
nature.  Its salts are very soluable in water and will remain so,
hence, it is considered a conservative element limnologically
speaking.  Sodium may be of natural origin or may be introduced
from industrial and municipal sources.

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                              88
     The sodium ion has been shown not to be toxic at levels



normally found in fresh waters.  Sodium chloride has been found



to decrease the toxicity of certain metallic compounds towards fish,








Observed Conditions



     Beeton  et al. (1967), reported sodium concentrations ranging



from 2 to 26 mg/1  (see figures 11, 15, and 16).  The average



concentrations for the inner bay were 15.8, 16.2 and 11.6 mg/1



for June 7, August 10, and October 30,1956 respectively and^simi-



larly, 4.3, 3.6, and 2.9 mg/1 for the outer bay.  The survey showed



highest concentrations at the Saginaw River mouth decreasing



to the Lake Huron background levels of 2-4 mg/1 (Allen,1964) in



the outer bay.  The June 7 survey showed higher concentrations in



the southeastern portions of the inner bay hinting of a possible



counterclockwise circulation.  The August 10 and October 30



studies showed equally high concentrations on both east and west



sides of the inner bay.  A low concentration tongue of waters



protruded into the center of the inner bay during the latter two



surveys.



     The 1966 Lake Survey study of the outer bay documented con-



centrations from 2.6 to 10.1 mg/1 with an average of approximately



3 mg/1.  No trends could be speculated from the data.



     No additional sodium data was available.  Overall high con-



centrations of sodium indicate definite contamination from the



Saginaw River.  The elevated levels, however, presented no threat




to aquatic life.

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                              89
Sulfate



General Considerations



     The sulfate ion is one of the major anions occurring in



natural waters.  It is important in public water supplies because



of its cathartic effect on humans at high concentrations (USPH



standards restrict sulfates to 250 mg/1).  Sulfate waters have



tendencies to form scales in boilers and heat exchanges.  Sulfates



are also important to biologic activity.  They are incorporated



into many proteins and organic matter.  Given low oxygen condi-



tions, the sulfur can also be reduced to nuisance sulfides.   Arti-



ficial sulfate sources include municipal and industrial discharges



and air pollution.







Observed Conditions



     The 1956 survey shows sulfate concentrations on June 7 ranging



from 8 to 42 mg/1, on August 10 from 10 to 28 mg/1, and on October



30 from 8 to 20 mg/1 (see figures 11, 15, and 16).  The con-



centrations were highest at the mouth of the Saginaw River de-



creasing in magnitude towards Lake Huron proper.  In the inner



bay, concentrations were generally less in the central region in-



creasing shoreward.  The average concentration for the inner bay



was greatest in the June survey (29 mg/1) declining in August to



22 mg/1 and, finally, dropping to 16 mg/1 in October.  Average con-



centrations in the outer bay were found to be 12 mg/1, 12 mg/1,



and 10 mg/1 for the same dates.

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                              90
     In 1966 the Lake Survey Center reported concentrations from



12 to 37 mg/1 for the middle and outer bay.  No observable dis-



tribution was noted.  Similar sulfate levels were found in the



1970 GLRD survey.  They reported an average concentration in the



bay of 12.8 mg/1, however, with a sampling emphasis on the outer



bay.



     In general, sulfate levels in the bay are greater than that



of Lake Huron where the concentrations range from 7 to 17 mg/1.



Saginaw River is an obvious contaminant source with reported con-



centrations of 70-115 mg/1 (Dow Chemical, 1956).  The sulfate




levels are not detrimental at present to water quality.







Temperature



General Considerations



     Temperature is a critical control parameter in aquatic



systems.  It regulates the seasonal stratifications and turnovers



and effects the growth, productivity, and cycles of most aquatic



organisms. Increasing temperature decreases gas soluability,



particularly oxygen, and increases gross respiration rates and



at times aquatic growth.  This results in increases in oxygen



consumption from the BOD and often nuisance growths of plant life.



Changes in temperature can alter the normal growth, development,



and spawning activities of certain organisms, often to the degree




that they can no longer exist.



     Michigan has set water quality standards for various water



uses  and ambient water temperatures.  In general they stipulate

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                              91
a maximum temperature and an induced variation of no more than
10 or 15° F, depending on the water quality and usage.

Observed Conditions
     Temperature data was available from 5 stations in Beeton's
1956 study, all stations in the 1966 Lake Survey study (outer
bay exclusively),  and from Michigan Water Quality Municipal Intake
data.  They all document Saginaw Bay to behave thermally much
like any midlatitude, fresh-water lake.  Temperatures range from
0° C  in the frozen waters, to 20-25° C. in the summer surface
waters.  Thermal turnovers occur in approximately May and October,
where depth is sufficient for stratification (primarily only in
the outer bay).  The thermal effects of the Saginaw River could
not be ascertained because of the lack of sufficient sampling
stations in the inner bay and the unquantified effects of solar
heating.
     Studies performed by the Consumer's Power Company in 1970
and 1971 document the thermal effects of their cooling water dis-
charges  in the vicinity of the Saginaw River.  A plume of surface
waters with elevated temperatures (2° or more) often extended
beyond 2 miles of the discharge area.  Temperatures immediately
at the discharge point were elevated frequently as much as 14° F.
The size and intensity of the plume was significantly altered by
wind conditions.  These discharge responses represent possible
violations of Michigan water quality standards.
     The discharge area is primarily marsh in character but can

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                              92
still be adversely affected by thermal contamination.  Effects



may extend to the bay as a whole by restricting spawning activities



of fish.  No positive confirmation of these effects was found.



     From very limited 1956 temperature data (Beeton  et al.,



1967) it appears that temperatures may have been higher in the



inner bay than in the open lake for the same dates (see figure



10).   If the difference does exist, the gradient would be at



most a few degrees centigrade.  A probable explanation is the



generally shallower waters and contamination from tributary



sources.








Trace Metals



     Trace metals are important nutrient requirements for all



organisms.  Growth and development can be severely limited by



the absence of one or more essential trace elements.  It has



been speculated that certain algal blooms may have been limited by



trace metal requirements.  Trace metals can also exert toxicity



in very low levels to aquatic organisms.  Despite their obvious



importance, no source of information was available on trace



metal concentrations for Saginaw Bay.



     Investigations need to be made to evaluate their importance



and examine for possible violations of water quality and drinking




water standards.



     Due to dredging and industrial activities, the trace metal



concentrations in Saginaw Bay are speculated to be elevated from




the background Lake Huron levels.

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                              93
Transparency



General Considerations



     Transparency is that quality of water which governs light



penetration or extinction.  It is typically measured in the field



as a secchi disc observation or in the laboratory as Jackson



Turbidimeter Units.  It is important to aquatic life because it



controls the magnitude of the euphotic zone and, hence, governs



primary production.  In certain eutrophic lakes, production can be



limited by the energizing light rather than chemical nutrients.







Observed Conditions



     The 1936 Saginaw Valley Report revealed Jackson turbidity



figures ranging from 75 at the mouth of the Saginaw River to 2



in the open bay.  Average figures in the open bay were approximately



10.  No other Jackson turbidity figures were available from other



sources.



     The 1970 GIiRD study reported an average transparency of 1.8



meters with sampling bias on the cleaner outer bay.  This trans-



parency is less than 1/5 that of the Lake Huron uncontaminated



waters.  No other transparency figures were available.







General Conclusions



     The existing water quality of the bay area directly reflects



the influence that human population concentrations and industrial



activity has upon the basin.  It is largely determined by the

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                              94
 inflow from the  Saginaw River which  carries  excessive quantities



 of  waste material  from  industrial, municipal, and agricultural



 sources.   These  effects are  apparent in  the  high dissolved solids



 content,  particularly chlorides and  nutrient enrichment.  The



 distribution of  these contaminants within the bay's surface



 waters  is controlled primarily by wind conditions, and may shift



 from day to day.




     Other sources of input  into the Saginaw Bay other than the



 Saginaw River are minor.  All other  flows combined amount to



 significantly less than that of the  Saginaw  River flow.  The dis-



 charges from the Au Gres and Rifle Rivers along the northwestern



 shores  may have had a diluting effect on the concentrations of



 various chemical constituents in the bay.  The low concentrations



 in  the  area,  however, were more likely due to inflow of Lake Huron



 waters  (Beeton  et al.,  1967).  Higher concentrations of nutrients,



 specifically  phosphorous and potassium, along the coastal portions



 of  the  bay indicate that agricultural runoff may be a significant



 source  of  contamination from all rivers and  shore areas.



     Overall, the physical-chemical  data on  Saginaw Bay is in-



 sufficient  for effective analysis of  trends both spatial and tem-



poral.   Except for the  1956 study by Beeto..  et al., the data



 lacks an adequate number and distribution of sampling stations.



Complete analysis for nutrients and other relevant chemical con-



stituents is needed and should be measured in surface and subsurface

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                              95
waters.  Accurate  statements concerning the circulation patterns
within the bay and the distribution and effects of concentrations
of chemicals cannot be made from surface data alone.

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                              96
                VI.  Biological Considerations







 Coliform



 General Considerations



     Natural waters can be carriers of pathogenic organisms.



 Because of difficulty in testing waters for pathogenic bateria,



 they are  instead analyzed for coliform bacteria, which are con-



 sidered to be an indication of fecal contamination.  Coliform



 bacteria  are themselves mostly not harmful; however, they are



 associated with pathogens because of their communal environment.



 High concentrations of coliform tend to indicate the existence of



 a potential health hazard.



     Sources of coliform bacteria are land runoff, waste dis-



 charges,  and any discharge that has come into contact with



 mammalian fecal material.  Since coliform can originate from



 many sources other than human excreta, it has been suggested



 that additional parameters such as fecal coliform aid fecal strep-



 tococci should be used for more precise evaluation.  Agreement is



 not total; because of coliform's large historical databank and



 its familiarity to water testers, it is continued to be used as



 the premier bacteriological parameter.



     The Michigan Water Resource Commission has set coliform



 standards for various uses of waters.  For "total body contact"



waters, the coliform levels are not to exceed 1000/100 ml.  If



 the natural background coliform level is above 1000 then the

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                              97
fecal coliform analysis is to be used in conjunction.  Fecal
coliform counts are not to exceed 100/100 ml.

Observed Conditions
     The principal source of bacteriological data is the Michigan
Water Resource Commission's "Report on Bacteriological Quality
of Michigan Surface Waters."  Unfortunately,it represents sampling
data only from near shore areas.  Also, of the 18 stations sampled,
there are none in the areas between the Saginaw River and Sand
Point.  In 1966 all mean total coliform concentrations were
measured to be less than 1000/100 ml  in the bay.  The geometric
means, representing anywhere from 5 to 72 samples, ranged from
151 at Point Lookout to 579 at Oak Beach  (on the northwestern
shore of the bay) with an average of around 200-250.  In general,
the 1966 concentrations are the same in Saginaw Bay as those
found on the other Lake Huron coastal samples, except for isolated
stations.  The 1967 bacteriological data showed a marked increase
in coliform.  The northeastern shores of the bay showed mean con-
centrations averaging below 1000 with a range from 429 to 1617.
The concentrations on the western shores were much higher, ranging
from 688 to 5676.  The 1968 data showed a similar trend, although
ironically the 1967 station with the highest mean (Whitney Twp.)
now had the second lowest mean of 287.  Both  1967 and 1968 coliform
concentrations were of the same magnitude as  those found at other

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                              98
 Lake Huron stations.   No identifiable,  consistent  spatial  trends



 can be derived from the coliform  distribution.   The  reported



 concentrations vary widely which  may  indicate highly variable



 contamination, variable mixing, or  possibly  poor testing technique.



      The Michigan WRC  has  also performed  fecal  coliform testing



 since 1967.   These data indicate  that mean concentrations  from



 the bay are  generally  well below  100/100  ml.  They averaged about



 20-25 with the means ranging  from 10  to 216.  No spatial or tem-



 poral trends were observed.



      Overall,  the bacterial concentrations in Saginaw Bay  are



 comparable to those found  in  the  majority of Michigan's eastern



 coastal waters.   Although  the total coliform counts  indicate



 that the waters are unsatisfactory  to allow unmonitored total



 body contact,  the fecal  coliform  counts indicate safe conditions.



 The  high coliform levels do present problems, however, to  water



 treatment operations.  They require more  intensive treatment and



 chlorination and  restrict  the lengths of  filter  bed  runs.







 Benthic  Fauna



 General  Considerations



     Analysis  of benthic microinvertebrate communities has proven



 to be a  valuable  tool in evaluating water quality.   Changes in



populations  or community composition  can  indicate changes  in en-



vironmental  conditions.  These effects may result from primary



environmental changes affecting the survival and reproductive

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                              99
capabilities of individual species or indirectly from interaction



with associated organisms.



     Benthic organisms are often classified into three basic



groups:  tolerant, intolerant, and facultative.  The tolerant



organisms are considered to be those that can survive and flourish



best in enriched or polluted environments.  Intolerant organisms



are sensitive to environmental stress and usually are not found



in polluted environments.  Facultative organisms can survive in



a wide variety of conditions.  By examining the distribution and



populations of these classes of organisms* both spatially and tem-



porally, conclusions can often be drawn concerning changes in



water quality.







Observed Conditions



     Information concerning the benthic invertebrates of Saginaw



Bay are available from primarily seven surveys:  The Michigan



Water Resources Commission in cooperation with Dow Chemical Company



carried out surveys in 1953, 1954, 1955, and 1965; the Michigan



Department of Conservation and the U.S. Fish and Wildlife Service



were responsible for a very thorough survey in 1956; in 1965



under the Great Lakes - Illinois River Basins Project of the



FWPCA benthic investigations were conducted on all of Lake Huron;



and in 1970 a study was conducted by the Great Lakes Research



Division of the University of Michigan.



     Overall, the bottom fauna of Saginaw Bay includes specie



representatives from several taxonomic groups.  The most prominent

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                              100
 forms  are  oligochaetes  and amphipods.  The following general



 observations  can be made:



     1.  The  Saginaw River has restricted benthic fauna in the



 inner  bay  to  predominantly pollution tolerant organisms, especially



 along  the  south and southeastern coasts.



     2.  Other tributaries to the bay do not appear to have



 limited benthic fauna.  They may, however, have increased biomass



 productivity  locally.



     3.  The  oligochaetes are the dominant organism in the inner



 bay.  Their populations have increased significantly in the



 past 15 years with present levels in the inner bay now ranging


                   2                                          2
 from a low of 500/m  in the Coreyon Reef to a high of 25,000/m



 at the mouth  of the Saginaw River.  Distribution may be related



 to bottom type.



     4.  Amphipods are dominant in the deeper outer bay with the



 common genus  changing from Pontoporeia to Gammarus southward.



     5.  The mayfly, Hexagenia, once common is no longer found



 in the bay.



     In general, although the productivity of the Saginaw Bay



 has increased in the last 15 years by estimates anywhere from two



 to sixfold;the data does not definitize any changes in water



 quality.   Positive statistical correlation of benthic distribution



was not possible.   The trends observed in the bay have, however,



been paralleled to those in western Lake Erie.  Comparisons between



 studies is difficult because of different sampling stations and



 sampling  methods.

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                              101
     The earliest studies were carried out by the Michigan Water


Resource Commission in 1953 and 1954.  The sampling emphasized


the perimeter of the inner bay.  Both studies demonstrated similar


benthic resources.  Tubificids (aquatic earthworms from the class


Oligochaeta) comprised the major portion of all samples.  They


made up 62% of the total number of organisms in the July 1954 study


during which time the genus Limnodrilus was most prominent (69%


of the Tubificids).  The average number of bottom organisms

                                                             2
present in 1954 was 279 per square foot (approximately 3000/m ),


an increase from 239 in 1953.  Tubificids were in greatest numbers


at the mouth of the Saginaw River and along the southeastern


shores.  A chi-square test was used to verify the significance of


the higher concentrations of tubificids on the eastern side of


the bay.  This distribution may be attributed to the organic


loading of Kawkawlin River, the Saginaw River with its prevailing


northeasterly flow/ and the discharges of the sugar beet and milk


plants in Sebewaing area.


     Cleanwater species were poorly represented in the 1954 samples.


Of the 17 samples taken they were absent or in quantities less


than 1% in 7 samples.   The sampling stations were located near the mouth


of the Saginaw River and along the southeastern shore.  Cleanwater


species average 6.0% at each station.  Only 3 samples had over


10% Cleanwater organisms, two of which were in the outer bay.


Interestingly enough,  the third with 27.4% cleanwater species was


located 6.5 miles northeast of the Saginaw River mouth.  The


prominent species there was Eurycercus lamellatus, a crustacean.

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                              102
     Other prominent invertebrates in the 1954 survey included
blood worms, Chironomus plumosus, and the burrowing mayfly
Hexagenia limbata which was found abundant at several stations.
Both were judged to have emerged just prior to or during the
survey due to the abundance of floating  exuviae.
     The June 1955 WRC survey sampled 19 stations in the
bay.  The pollution tolerant tubificids were still dominant,
representing 63% of all the organisms.  The average number of
organisms per square foot increased 17.3% over 1954.  In general,
the benthic conditions seemed to be improved.  The average number
of species per sample increased from 8.7 in 1954 to 10.4 species
per sample in 1955.  Although tolerant species were dominant,
cleanwater species were not present in all but 4 samples.   The
mean station percentage of cleanwater organisms was 13.1%.  Ten
of the samples had communities in which over 10% of the organisms
were cleanwater invertebrates (5 were over 20%,  the highest
being 66.5%).  The cleanwater midge larvae Cryptochironomus
digitatus was also found in over 50% of the samples.
     The validity of this pronounced increase in water quality
as indicated by the benthic fauna is, however, questioned.  Due
to the high variability of the Saginaw Bay sediments and the
absence of duplicate samples, this author doubts that any increase
in water quality can be documented, particularly within a one-
year period.  It also appears from the bottom description that
the 1955 benthic samples were taken from locales that were gen-

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                              103
erally more sandy in nature as compared with the 1954 samples,

which were described generally as muddier.  It can be concluded,

that the problem area in both studies was between


the Kawkawlin River and Sebewaing.  Low numbers of cleanwater

organisms and high concentrations of tubificids were found in

these areas.

     In 1956, 1000 bottom samples were taken from Saginaw Bay


between June 1956 and March 1957.  Schneider, Hooper, and Beeton

reported the major results Of this study in 1969, while Brinkhurst

reported specifically on the oligochaetes in 1967.  The average

standing crop of benthic invertebrates found from this survey

            2                                           2
was 4.43 g/m ,  in contrast with an estimate of 15.1 g/m  for the

1955 WRC survey.  The comparison is marginal, however, because of

different station distributions.  The 1955 study included only

3 of 19 stations in the outer bay while the 1956 study had 11 of

51, that also included deep water stations, unlike the 1956 study.

     Schneider  et al., found it difficult to statistically

associate distribution of benthic fauna with other water quality

parameters.  Some relationships were still observed.   Highest

biomass production was noted in the southern third of the bay
         2
(4.72 g/m ).  Lowest productivity was in the outer third of the
             2
bay (3.46 g/m ).  Areas of highest biomass included the deeper

waters of the inner and outer bays and Wild Fowl Bay.  The shallow

and sandy Coreyon Reef was the least productive.   Among all the

stations, oligochaetes and chironomids were most prominent, com-

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                              104
prising two-thirds of the total number of organisms.  The oligo-



chaetes constituted over 50% of the crop in the southern third



of the bay, but distribution within the bay appeared to be mostly



haphazard.  The highly tolerant oligochaet, Limnodrilus hoffmeisteri,



was again prominent in the southern bay and appears to correlate



well with the known flow of the Saginaw River, along the north



and south shore  depending on wind direction.



     Amphipods, particularly Pontoporeia, were predominant in the



outer bay with highest concentrations in the deepest stations.  The



variation in numbers appeared to be correlated with depth.  Other



organisms found include chironomids and mayflies which made up



the majority of the biomass in the middle third of the bay area.



The amphipod Gammarus was also common.  Oligochaetes made up 22%



of the biomass, 54% in number.  Sphaeriid clams were noticably



rare as compared with the 1965 study.



     In 1965 the WRC followed up their previous work with another



study including 43 stations.  They concluded that the benthos



did not indicate any significant changes in water quality since



the 1954 and 1955 surveys.  The bottom samples demonstrated similar



distribution of indicator organisms.  Oligochaetes were again



dominant, particularly in the inner bay, comprising from 18% to



99% of the total number of organisms.  Midge larvae made up the



majority of insect population that was found.  In contrast to



the earlier WRC studies, but in agreement with the 1956 survey,



the cleanwater mayfly, Hexagenia limbata, was not found.  In all,

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                               105
50 different kinds of organisms were identified.  The  investigator



in this study concluded that "water from the Saginaw River  limits



the bottom life to pollution tolerant forms in an area from the



river mouth to the deep water off Point Au Gres and includes the



shallow southeast protion of the bay southwest of fish points."



He further classified the shallow north side of the bay as  a



facultative environment and the outer bay a cleanwater environment.



The main source of pollution to the bay was attributed to the



Saginaw River.  All other tributaries, including the Kawkawlin,



Rifle, and Au Gres Rivers, exerted no limiting effects on the



fauna.  For example, diversity was found to be greater at the



mouth of the Kawkawlin River than at stations both north and south



of the river.



     The FWPCA 1965 survey (Schuytema and Powers, 1966) (figure 19)



again documents what now appears to be the prominent distribution.



Oligochaetes were the most numerous organisms found in the  bay,



comprising 78% of the total population.  Oligochaete concentrations



were higher in the western portion of the inner bay (average



2-4000 organisms/m2) than in the eastern portions (average  <  1000



because of differences in bottom type.  Although only  8% of  the



organisms in the bay were amphipods, they dominated the outer bay



samples.  Pontoporeia affinis was the dominant amphipod at  the



mouth of the bay,  while in the middle bay Gammarus predominated.



     An interesting comparison of the WRC 1955 survey,  the



1956 survey,  and the Schuytema and Powers 1965 survey was



made by Schneider et al.  (1969).  In 1956,  a die off of

-------
                                         106
1965.
   Mean populations of oligochastes in Sagisaw Bay, numbers/in2, April-September
                                                     V
T9 -   -  Meaa populations of ejnphipods in Sagicav/ Bay, Bis

            source:  Schuytara and  Powers 1966
                                                               .-, April-September 135 5

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                              107
both mayflies (Hexagenia) and fingernail clams was observed.  The clam

population recovered by 1965; but the mayflies did not.  This indicated
some catastrophic event occurred in 1955 or 1956 from which only

the clams were able to recover.  A comparison was drawn to the

mayfly die off in western Lake Erie causedby low dissolved oxygen.

High turbidity could have also been a factor, however, in Saginaw

Bay.

     The most recent benthic study was the 1970 survey of 7 sta-

tions in the bay by GLRD of the University of Michigan.  They

did not document any new trends.  Amphipods were still predominant

in the outer bay with the dominance changing from Pontoporeia

to Gammarus southward.  Oligochaetes were as usual found to flourish.
                                                                 2
The outer bay stations had standing crops of 400-1700 organisms/m

while the inner and middle bay stations showed higher numbers,
                     2
3200-6000 organisms/m .  The once prominent mayflies were not col-

lected.  The GLRD observed an increase in oligochaete populations

from 1965 to be as much as sixfold, ignoring sampling bias.

     Detailed studies of the specific regions near the Saginaw

River and Quinacassee Bay have been carried out for Consumers

Power Company since 1970.  Thermal discharges from the Kearn-

Weadock power plants near the Saginaw River restricted the already

limited benthic populations within a 1/2 mile radius of the dis-

charge.  The thermal discharges from the Kearn-Weadock power plants

were suggested to have limited the population densities within

this range.  At an intermediate distance from the discharge

(1-2 miles) oligochaete populations were observed to increase,

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                               108
 reflecting a diminished yet existing thermal effect, since sensi-



 tive organisms were still repressed.  Beyond a three-mile radius,



 worm densities were noted to decrease while more sensitive organ-



 isms  (chironomids) were noticed to increase in population.  This



 reflects a partial return to normal biological conditions.



     The benthic invertebrate fauna at the Quinacassee site was



 found to include primarily midges and oligochaetes.  Population



 densities were low, averaging less than 250/m .  This is attributed



 probably to the bottom type, a sand and gravel constituency.



     The Michigan WRC has also carried out studies on the Sebewaing



 Bay area which receives discharges from two industries, a sugar



 company*and a dairy.  In general, they found in 1970 primarily



 oligochaetes and midges.  This is in contrast with a 1957 WRC



 study which found other organisms in addition, including leeches,



 fingernail clams, snails, scuds, mayflies, caddisflies, and other



 dipterian species.  The average number of species per sample



 dropped from 10.4 to 3.5.  According to the WRC, "these data re-



 flect a gross change in the quality of Sebewaing Bay over the



 last 13 years.  The decline in species. . .indicates a serious



 degradation of environmental quality.  This degradation is a



 reflection of the general decline in Saginaw Bay water quality.



Organic discharges to Sebewaing Bay such as those of the Michigan



Sugar Company are strong influencing factors."

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                              109
Plankton and Macrophytes
General Considerations
     Plankton and macrophytes together constitute the base of
the entire aquatic food web.  They are the primary producers
and primary consumers in all aquatic ecosystems.  Plankton are
small, free-floating organisms found in natural waters.  They
include both plant and animal life and are usually divided into
two classes, phytoplankton or algae and zooplankton.  Phytoplank-
ton are primary producers and are the main source by which light
energy is incorporated into aquatic biomass.  Zooplankton can be
considered to be the next link in the food chain, feeding on
phytoplankton.  They are often termed primary consumers.  Both
are grazed on by higher aquatic organisms.  Because of their
elementary association with the physical and chemical characteris-
tics of the water, they are affected by changes in water quality.
Their populations, growth characteristics, and species composition
are often used to evaluate the state of water quality.  Changes
in their characteristics can generate other changes higher up the
food chain.
     Macrophytes can be described as aquatic plants.  These may
be rooted in the sediments or floating.  They, like phytoplankton,
are important because they are primary producers.  They are auto-
trophic and can incorporate inorganic materials and light energy
into organic biomass.  Besides their role as a primary producer,
they are significant as "nutrient pump^" returning nutrients from
the sediments back to the water column as biomass.

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                              110
Observed Conditions



     Little significant work is available on Saginaw Bay phyto-



plankton.  What information was found indicates very high pro-



ductivity in the bay.  Limited amounts of data were available from



the 1970 University of Michigan GLRD survey.   It documented



algae levels averaging 7.26 mg/1 as chlorophyll a at 3 meters.



This concentration is 8 to 9 times the level found in the Lake



Huron proper.  Carbon fixation measurements showed similar high



productivity, 31±23 mgC/m /hr at 0 meters and 28±17 mgC/m /hr at



3 meters.   (These values are means from 5 samples with the figure



following the ± indicating a standard deviation).  The highest



fixation rates were found in the innermost bay stations.  The mean



values showed productivity to be anywhere from 15 to 30 times that



measured in the open lake.  The mean assimilation rate was 4.16



mgC/hr/mg Chi a, 1 1/2 to 3 1/2 times greater than the Lake Huron



ratio.  This may be a reflection of the low nitrate, high phos-



phate conditions in the bay.



     Taxonomic analysis of the bay's phytoplankton show sig-



nificantly fewer diatoms than in the open lake.  Ceratium was



the dominant genera, common or abundant at five of their six



stations.  Microcystis was common or abundant at four stations.



Aphanizomenon and an unidentified organism, possibly a blue-green



but also possibly a sulfur reducing bacteria, were common at the




three middle bay stations.



     An additional source of phytoplankton data was a 1972 survey



by the CCIW.  Chloryphyll a levels were found to average from

-------
                              Ill
4 to 12 mg/1 Chi a with the higher values in the inner bay.
Concentrations at times ranged as high as 20 mg/1.  This data
agrees well with the GLRD report.  No taxonomic data was available.
     Limited studies were done by Beak Consultants Inc. for
Consumers Power Company in 1970 and 1972.  Samplino stations were
primarily along coastal zones (within 3 miles of shore) from
Pinconning to Sebewaing.  In 1970 only plankton volumes were taken
averaging 4 mls/m  of strained lake water.  In 1972 taxonomic
studies were undertaken on phytoplankton.  Populations were
typically quite diverse.  Diatoms were not well-represented, al-
though Fragilaria was present at all stations.  The dominant greens
were Ulothrix and Pediastrum, although large masses of Microtham-
nium were found in the marsh areas not sampled.  Ceratium was
represented well at all stations.
     Data concerning the macrophytic populations was scarce, the
only source being the previously mentioned Beak Consultant studies.
Sampling was, however, only carried out in the areas southeast of
the Saginaw River, near the locale of the Kearn-Weadock power
plant discharge.  Ten macrophytic families were identified.  They
were, Ceratophyllacea (coontails), Cypheceae (sedges), Gramineae
(grasses), Juncaceae  (rushes), Lemnaceae  (duckweed), Najadaceae
(naiads), Plantaginaceae (plantains), Potamogetonaceae (pondweeds),
Salicaceae (willows), and Typhaceae (cattails).
     Information on the zooplankton communities was restricted to
the limited 1970 GLRD study.  Settled volumes of zooplankton did
not indicate degraded water quality.  The mean volume was .67 ml/m ,

-------
                              112
 slightly below the mean found in the open lake.  In the outer



 bay Bosmina and Asplanchna were most abundant with Diaptomus,



 Cyclops, and Leptodora less abundant.  In the middle and inner



 zones of the bay an unidentified rotifer was predominant.  Bosmina,



 Diaptomus, Daphnia, Asplanchna, and Cyclops were common.  No



 authoritative water quality statements can be drawn from this data,



 although the rotifer and Bosmina population distributions indicate



 possible eutrophication.







 Fish



 General Considerations



     Fish is a valuable direct aquatic resource for man and is



 harvested commercially and by individual sportsmen,  it also



 represent a major element in the recreational potential of an



 aquatic system.  Millions of dollars are spent annually on sport



 fishing activities.  Fish populations and species composition are /



 hence.carefully monitored by both industry and sportsmen.  Changes



 in fish populations can be a result of numerous factors including:



 changes in water quality affecting fish directly; changes in water



 quality which disrupt the food chain and affect fish indirectly;



 exploitation; uncontrolled natural or introduced predation; changes



 in the physical character of the ecosystem disrupting the spawning



 or growth cycles, etc.







Observed Conditions



     Traditionally Saginaw Bay has been a prominent commercial and

-------
                              113
recreational fishing resource.  Over 90 species have been
recorded in the bay, including lake herring, smelt, chubs, white
sucker, channel catfish, yellow perch,  walleye, whitefish, lake
trout, bullheads, rock bass, carp alewife, small mouth bass, nor-
thern pike, rainbow trout, coho salmon, and numerous forage and
non-commercial fish.
     Commercial fishing became an established industry in Saginaw
Bay in the mid 1800's in response to the expanding population
and onset of the industrial revolution.  Fish production rapidly
rose in the 1800's, and peaked in 1902 with a fantastic 14,182,000
pounds of production.  The fish production has, however, decreased
gradually since then to a low of 2,557,000 pounds in 1966.  No
reversal in this trend is foreseen.  The decline has been the
result of changes in species composition which was brought about
by a combination of factors.  These include sea lamprey and alewife
disruption, exploitation, pollution, and habitat changes.  Eco-
nomic squeeze has also taken its toll with increasing costs often
restricting a profitable harvest.
     The principal source of information on Saginaw Bay's fish
resources originate from the Fish and Wildlife Service of the
U.S. Department of the Interior.  Two very useful  studies were
published:  "Fluctuations in Commercial Fisheries  in Saginaw Bay
1885-1956" and "Fish and Wildlife as Related to Water Quality in
the Lake Huron Basin."  Numerous other studies have been carried
out on the bay's fish resources, but they are on more specific
topics such as:  the fluctuations in growth and year class strength

-------
                              114
of walleyes; food of the American smelt; and fluctuation in popu-
lations of yellow perch.  All these studies indicate the same
conclusions, that the fish resource? in the Saginaw Bay have
been severely altered in the last century and that the commercial
fish industry there is endangered.
     Prior to 1930 no dramatic alterations in the fish community
had been noted.  Lake herring was the dominant species with catches
ranging from 1 to 8 million pounds.  A typical catch in
that period was 3 to 4 million pounds per year.  Walleye, yellow
perch, and suckers were also abundant, each amounting to approxi-
mately 1 million pounds per year.  Whitefish and lake trout,
although not as abundant, were still very valuable resources with
typical productions of 50,000 and 30,000 pounds per year respec-
tively.  The two most significant occurences in this period were,
however, the appearance of carp and the decline of lake sturgeon.
Carp, introduced to the U.S. in 1874, amounted to approximately
10% of the catch by 1918.  The decline in lake sturgeon,from
81,000 pounds in 1885 to practically nothing in 1928, was at-
tributed to an intensive effort to remove sturgeon from areas where
they damaged gear used to fish for other species.
     Beginning in about 1930, dramatic changes in species production
were realized, and the consequential decline in fish production
was observed (see Tables 5 and 6).  Lake trout was the first
species to be affected.  Because of the variability in the areas
included in the reported statistics, the lake trout catch appears

-------
                 xaoie b  source: Fish and Wildlife Div.  Dept. of Interior 1969
     vss U. G. Commercial Fishery Production for Bpcoiiiea .reraouB  ui «xu« J««AJVJ.
Lipccion In Caginav Bay and Lake'Huron.Excluding Saslnaw Boy.
Sp.rcies
Carp
• Open Lake
Saginaw Bay
Catfish
Open Lake •
Saginaw Bay
Chubs
Open Lake
Saginaw Bay
Herring
Open Lake
Saginaw Bay
Lake Trout
Opcm Lake
Saginaw Bay
Suckers
Open Lake
Saginaw Bay
Walleye
Open Lakes
Saginaw Bay
Whitefioh
Open Lake
Saginaw Bay
Yellow Perch
Open Lake
Gaginaw Bay
TOTAL (All Spe
• Open Lake
Saginaw Bay
1930-34

25
•925

P*
45

: 517
• tr

927
2901

1639
260

852
1305
/
169
. 1173

! 2112
1282

101
517
cies)
6410
8602
1935-39

45 '
.794

' ' ' 2
102
'
256.
tr

1056 ' •
3823 . ,

'1350
75

846
• fl^Q

1 *7K
1379

918
116

148
606

4880
7837
(•Thousands of Pounds)
1940-44 1945-49 1950-54

;% '163
! '729
• , .,
' ;', 10
^340

• 141
,' tr
•
. .563
1827

602
74

491
809
•
100
1501
V
127
19

-: 90.
530

2359
5891

- .. 146 -•
1409

' . 6
249

133
tr

• v 496
1003

• 42
4

473
889
,
101
• . . 411 •

943
507

' 56
394

2450 •
4964

211 •
1247

8
248

120
3

417 '
1098 -

tr '
tr

. 236 .
904 '

108
64

. 123
11

69
376

1348
4178
1955-59

63
1420

5
311

850
74

4l
87 .

tr


"66
• . -540

74
62

59
3

98
319

1311
3023
1960-64

68
1343

3
201

2086
247

17
23 ..

tr


1*8
484

63
*j
59

225
47

'189
375

2743
2944
196s)

fro
•1384."

1
145

1326
21

42
tr


M

36
353

76
I w
25

172
3

71
895

1788
SR85
1060

62
769

2
164

802
5

16
tr


"H
-H
en
14
299

31!
17

171
1

97
1221

1212
2557

-------
Table 6   source: Fish and Wildlifo Div. U.S. Dept. of Interior 1969
	 ...,-r, >.., 	 • i ^_ ivrceivcafic composition uy
• • " for Specified Periods in
Species
Carp
Open Lake
Saginaw Bay
Catfish
Open Lake
Saginaw Bay
Chu"bs
Open Lake
Sae'inaw Bay
Herring
Open Lake
Sasinaw Bay
Lake Trout
Open Lake
Saginav Bay
Suckers
Open Lake
Saeinaw Bay
Walleye
Open Lake
Saginaw Bay
Whitcfish
Open Lake
Saginaw Bay
Yellow Bsrch
Open Lake
Saginaw
1930-3^

tr
11

tr
tr

8-
tr

ll*
3'i

26
3 .
,
13
15
3

' 33
15
2
6
1935-39 IS

1
10' '

1 .
1

5
tr

22
1*9

28
/ ^

17
11
I* '
18
19
1
8
)1*0-M* 19
. •
7
12

6
6 .

6
tr

2l*
31

25
1

21
1*
25
5 • •
tr
1*
9 '
Major a
Saginaw
il*5-l*9

6
28 '

5
5 .

5
tr

20. '.
20

2
tr
•
19
18
1*
8
38
10
2
8
pccies or Ut
Bay and Lake
1950- 51*
•
16
. 30 '

6
6 •

9
tr

31
26

tr
tr

17
22
8
2
', 9
' ;tr
. .5
Ht commercial Fishery Product ion
Huron Excluding Saginav Bay*
1955-59

5
>7

10
10

65
2

• 3
3

tr
w ••

5
18
6
2
tr
tr
, 7
10 .
1960-64 .

2
1*6

7
7' '

76
1

1
1

-.-
•* «•

2
. 16'
2
2
8
.-
7
13
1965.

2
1*8

5
5

7!+
1

2
tr

--
""

2
12
1*
1 !.
• 10
tr
1|-
31
1966

5
30

6
6

66
tr

1
tr

__


12
3
1
ll*
tr
a
1(8
                                                                                                  CTl

-------
                              117
to have increased t6 an average catch of 260,000 pounds for 1930-
1934.  This increase may or may not be actual.  What is definite,
however, is the significant decline thereafter in lake trout
resulting from the introduction of the predatory marine sea lam-
prey.  The average production for the period from 1935 to 1944
was 1/3 to 1/4 of earlier catches.  By 1950 the lamprey had taken
its toll; trout Were no longer a viable commercial fish catch,
recorded to be only caught in traces.  Since 1955 zero commercial
production of lake trout has been recorded.
     Whitefish demonstrated an even more catastrophic decline.
In the period 1930 to 1934 whitefish constituted 15% (1,282,000
pounds per year)  of the total Saginaw Bay catch.  Exploitation
in this period, through use of the deep trap net, resulted in a
decline in production to 116,000 pounds per year from 1935-1940
and 19,000 pounds per year for 1940-1944.  Restrictions placed
on the deep trap net in 1935 did not, however, stop the decline,
and predation by sea lamprey was now the controlling factor.  A
brief upturn in catch occurred in 1946-1948 due to a strong 1943
year class; but, aside from then, the valuable whitefish are now
scarce.  In 1966 only 1000 pounds of whitefish were caught
     Walleye production in Saginaw Bay fluctuated without a long-
term trend until the 1940's.  Between 1930 and 1940 the production
had risen to over 1 million pounds in all years except 1931.  Walleye
represented from 7 to 21% of the total catch.  After 1943, pro-
duction began to decline progressively.  In 1966 walleye pro-

-------
                              118
duction represented only 1% of the total Saginaw Bay catch, a
production of just 17,000 pounds.  The decline has been speculated
to be a result again of sea lamprey predation.
     Smelt landings up until 1941 were nonexistent.  In 1950,
production rapidly increased to a peak of 218,000 pounds per year
in 1951.  Thereafter, however, it decreased similarly as it did
in all of Lake Huron/ and in 1966 only 2,970 pounds were caught.
     Of the other remaining principal species, there has been
no scarcity in Saginaw Bay in recent years.  Because of economic
considerations,  the fishing intensity with regard to many species
has declined and, hence/ apparent catch figures decreased.  White
and red horse suckers are a good example of this phenomenon.
Despite rising abundance of fish, sucker production has decreased
from 1,305,000 pounds per year (1930-1934J  to just 299,000 pounds
per year in 1966.  Fishing intensity for suckers has decreased
steadily since 1937.
     Lake herring demonstrated a similar trend until 1952.  Fish
production had fallen to 1/3 of the 1930-1934 catch figures.  From
1952 on, however, lake herring catches dropped even more dramati-
cally.  This may not have been a principal result of decreased
fishing intensity but a consequence of the 1952-1954 explosion
of alewife populations.  In 1966 only trace landings of lake
herring were reported.
     Production of carp has increased in recent years despite
decreases in fishing intensity.  The bay populations are so great

-------
                              119
that they have overridden the declining fishing pressures and



now constitute between 30 and 50% of the total catch.



     Until the early 1960's, production of yellow perch had been



gradually decreasing because of declining fishing pressure.



Abundance, however, was increasing.  Beginning in about 1963



perch production rose sharply from approximately 278,000 pounds



to 1,221,000 pounds in 1966.  The increase has been attributed



to increased fishing intensity.  Fishing pressure increased



because of relaxed regulations on perch fishing and, more im-



portantly, the decline in Lake Erie production.



     The catfish is the only species in Saginaw Bay for which



production, availability, and fishing intensity have been con-



sistently above the 1929-1943 average.  There has existed a



fairly steady supply and market for catfish in recent years.



There appears to be a periodic fluctuation in catfish production.



High production of over 300,000 pounds per year was observed



in the early 1940's and late 1950 's, and low production was ob-



served before 1940, in 1950, and decreasing production 1960-1965.



There were 164,000 pounds of catfish landed in 1966.



     The only other significant change in production trends has



been the gradual increase in chubs.  Following the decrease



in lake trout, whitefish, and walleyes, the number of chub landings



increased from just a trace in 1949 to a peak of 3.2 million



pounds in 1961.  The chub production has declined since then to



5,000 pounds in 1966.  This fluctuation in chub production has

-------
                              120
 similarly been noted  in other great lakes.



     Overall, the commercial fish industry in Saginaw Bay is



 today  in a very depressed condition, despite attempts to control



 invading marine species, stop commercial exploitation, and



 stock desirable fish.



     Besides the commercial fishing industry, Saginaw Bay supports



 an active and diverse year-round sport fishery.  Perch and bass



 are probably the most important species, with pike, catfish,



 walleye, and carp also important, especially in the shallow, weedy



 portions of the bay.  Rainbow trout have been landed in the



 outer bay.  Recently coho salmon have become important due to an



 extensive stocking effort in the Au Gres and Tawas Rivers.



 Numerous other fish are caught for sport in Saginaw Bay tributaries,



     Sporadic complaints have come in over the years concerning



 fish taints.  These complaints are rare, however, in recent years.



 The taints were possibly due to trace organic chemicals origin-



 ating from the Saginaw River.  Positive identification of the



 exact source is not always possible.  Dow Chemical Company of



Midland has now taken extreme measures to eliminate the discharges



 of any organics which might institute such taint problems.  Com-



mercial fishermen feel that the taint problems are no longer



 significant.

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                              121



                          APPENDIX A

                 Persons and Agencies Contacted

Army Corps of Engineers
     Jack Collis
     Elihu Jackson

Bureau of Sport Fisheries
     Ray Argile

Canadian Center for Inland Waters
     Keith Rogers
     W. A. Glooschenko

Consumers Power Company
     Jackson, Michigan

Dow Chemical Company
     Midland, Michigan

Environmental Protection Agency  (Chicago)
     Don Walgren
     Bill Frans

Great Lakes Basin Commission
     Mr. Hall
     Barb Kollar

Great Lakes Research Division
University of Michigan

International Joint Commission
     Gary Guenther

Lake Survey Center, Detroit
     Dr. Pinsak

Michigan Water Resource Commission
     Biological Division
       Ron Willson
     Comprehensive Studies
       Bill McCraken
       Fred Morley
     Industrial Waste Water Division
       Galen Kilmer
     Municipal Waste Water Division
       Thomas Hoogerhyde
       Michael Smith

Saginaw Midland Water Supply Advisory Board

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                                122
                           APPENDIX  B

      Annotated  Bibliography on the  Saginaw Bay Basin


Allen,  H.E.   "Chemical Characteristics of South Central Lake
           Huron."  Great Lakes Research Division, University of
           Michigan, Ann Arbor.  Pub. #11, 1964.

           Presentation of the chemical analysis from a 1956
           survey of Lake Huron.  Including sampling stations at
           the mouth of Saginaw Bay and along a transect of South
           Central Lake Huron.


Ayers,  John C.   "The Currents of Lakes Michigan and Huron."
           GLR Institute, University  of Michigan, Ann Arbor, 1959.

           A study of lake currents with only limited mention of
           Saginaw Bay.  Includes an  abridgement of the following
           publication.


Ayers,  John C.;  Chandler, D.C.; Henson, E.B.; Lauff, G.H.; and
           Powers, C.F.  "Currents and Water Masses of Lake Huron."
           University of Michigan, GLR Institute, Ann Arbor.  Tech.
           Paper  #1, 1956.

           A more detailed examination of currents in Lake Huron,
           although significant attention was placed on Saginaw
           Bay.   Included extensive drift bottle studies.  The
           article was concerned with primarily surface currents.


Batchelder, T.L.  "Saginaw Bay Basline Ecological Survey, 1971.
           Waste  Control Dept. Dow Chemical Co., Midland, Michigan,
           1973.

           A significant limnological study of 29 bay stations
           carried out in August to September of 1971.  Routine
           chemical analysis was performed on the water including
           those  for D.O., nitrogen and phosphorous compounds, and
           most major anions and cations.  Additional chemical
           analysis was made on the bottom sediments with special
           emphasis on heavy metal concentrations.  Biological
           information was also gathered including phytoplankton
           and benthos investigation.  PCB levels were also
          measured in numerous carp.  Unfortunately the information
           from this report was not available in time to be included
           in  the text.

Beak Consultants.  "Biological Survey of Saginaw Bay, 1970."  For
          Consumers Power Company,  Jackson, Michigan, January 1971.

          A biological  survey including sampling of benthos,
          plankton,  fish,  macrophytes.   Intended to evaluate

-------
                                123
             impacts of power plant discharges  in  the vicinity  of
             Saginaw River and Quinacassee.


Beak Consultants.  "A Biological Survey of Saginaw Bay,  1971."
             For Consumers Power Company, Jackson, Michigan,  1972.

             A similar study to the 1970 survey except in this  survey
             only benthos and fish were sampled.


Beeton, A.M.  "Relationship Between Secchi Disc Readings and Light
             Penetration in Lake Huron."  Trans. Amer. Fish Soc.
             87th meeting.  Pub. 1958.  p. 73-79.


Beeton, A.M.; Smith, S.H.; and Hooper, F.H.  "Physical Limnology
             of Saginaw Bay, Lake Huron."  Great Lakes Fishery
             Commission, Ann Arbor, Michigan, 1967.

             Results of a thorough 1956 survey of Saginaw Bay.  In-
             cluded physical and chemical analysis, flushing rates,
             and transport calculations.  Overall, a very well done
             study.


Bretz, J.H.  "Causes of Glacial Lake Stages in Saginaw Basin,
             Michigan."  Journal of Geology, vol. 59, 1951.  p. 244-
             258; p. 137-143.

             Discusses the geologic history of the Saginaw Basin
             area.  Not of much use beyond geological interests.


Brinkhurst,  R.O.  "The Distribution of Aquatic Oligochaetes in
             Saginaw Bay, Lake Huron."  L & 0, vol. #12,  No. 1, 1967.

            A detailed analysis of species distribution of Oligo-
            chaetes in Saginaw Bay from a 1956 survey.   A good
             study, however,  no profound conclusions could be drawn.


Carr, I.A.   "Distribution and Seasonal Movements of Saginaw Bay
            Fishes."   U.S.  Fish & Wildlife Services,  Pub. #417,
            April 1962.

            Evaluation of a 1956 survey of Saginaw Bay with regards
            to numbers and species of fish found,  where  and when.
            No concrete  generalizations were made.


Consumers Power Company.   "Investigations  of the Terrestrial
            Biota on  the Quinacassee  site,  Autumn  1972."

            A good analysis  of  the terrestrial  environment.   It
            also offered climatology  data  and limited amounts of

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                                124
             bay levels information.


 Consumers Power Company.   "Biological Survey in the Vicinity of
             the Quinacassee plant site."   Jackson,  Michigan,  June
             1973.


             Results of a  1972 survey of the Quinacassee  area,
             examining plankton,  benthos,  and macrophyte  populations.
             Intended to evaluate the impact of  their power  plant
             discharges.


 Consumers Power Company.   "Consumers Power Company  1971  Water
             Quality Surveys."

             Several temperature  surveys done to evaluate the effects
             of power plant discharges in  the vicinity of the
             Saginaw River.


 Consumers Power Company.   "Environmental  statement  related  to the
             construction  of Midland  Plant Units 1 and 2."   U.S.
             Atomic  Energy Commission,  March 1972.

             An environmental  impact  statement with  regards  to the
             Midland plants  and their impact on  the  Tittabawassee
             basin.


 Canadian  Center for Inland  Waters.   "Limnological Data Report #1."
             Turlington, Ontario,  1968.

             The results from  August  cruises of  Lakes  Huron  and
             Superior.   Had  limited amounts  of information on
             Saginaw Bay.


 Dow Chemical Company.   "Ecological Survey of  the Saginaw River and
             its major  tributaries with  special  emphasis  on  the
             Tittabawassee River."  Dow  Chemical, Midland Division,
            Waste Control Dept.,  1973.

            Overall  a  good  ecological survey  of 16  stations  in the
            Saginaw  system  including  4  on the Saginaw River and
             9 within the Tittabawassee  River  system.   Physical
            and chemical measurements were  made including those  for
            solids, alkalinity, specific  ions,  nutrients and metals.
            Biological  investigations included  those  for periphyton,
            macroinvertebrates, and  fish.


Dow Chemical Company, Midland Division.   Chloride concentration
            charts of the Saginaw Bay.

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                               125
            These were unevaluated color coded chloride concentra-
            tion charts of the bay available since 1935 at various
            times.  The only good comprehensive source of chloride
            information on the bay.


El-Zarka, Salah El~din.  "Fluctuations in the populations of
            yellow perch in Saginaw Bay, Lake Huron."  U.S. Dept.
            Interior,  Fish and Wildlife Division,  Fish Bui. #151,
            volume 59, 1959.  p.  365-415.

            A discussion of growth rate, age composition,  size
            distribution, length-weight ratios, and sex ratios of
            perch catches from 1929-30 and 1943-55.

 Environmental Protection Agency.   "STQRET Data."

            A retrieval of all physical and chemical water quality
            data for the Saginaw  Basin available from the national
            STORET systems.

 Gordon,  William G.  "Food of the American Smelt in Saginaw Bay,
            Lake Huron."  Transactions of American Fisheries Soc.,
            vol. 90, No. 4, October 1961.  p. 439-443.

            A 1956 stomach analysis study of 411 smelt caught in
            Saginaw Bay.

 Great Lakes Water Quality Board.   "Great Lakes Water Quality."
            International Joint Commission, April  1973.

            Contained limited information on the nutrient and algal
            concentrations of Saginaw Bay.  Contained  isogram
            plots of concentrations in Lake Huron.

 Great Lakes Basin.  "Framework Study, Appendix #7 Water Quality,
            Draft No.  2."  Ann Arbor, Michigan, March 1973.

            With regards to the Saginaw Basin, it is primarily an
            evaluation of water quality and discharge treatment
            recommendations.  It  contained coliform, transparency,
            and oxygen isograms charts on Saginaw Bay.

 Hile, Ralph.  "Fluctuations in Growth and Year-class Strength of
            the Walleye in Saginaw Bay."  U.S. Dept. Interior,
            Fish and Wildlife Service, Fish Bull.  #91, 1954. 38 p.

            Over 6000 fish were collected and examined from 1926-30
            and 1943 in Saginaw Bay.  They were examined for age,
            length, weight, growth, etc.  Appropriate conclusions
            were drawn.

 Hile, Ralph.  "The Increase in Abundance of the Yellow Pike Perch
            in Lakes Huron and Michigan in Relation to the Arti-
            ficial Propagation of the Species."  Trans. Amer. Fish-
            eries Soc., Vol. 66,  1936.   p.  143-159.

 Hile, Ralph and Howard J. Buetlner.  "Fluctuations in the Com-
            mercial Fishes of Saginaw Bay 1895-1956."  U.S. Dept.

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                              126
           Interior, Fish and Wildlife Division,  Report #51,  1959.  38p.

           A thorough report on the composition of the commercial
           fisheries catch since the late 1800's.  Figures as
           well as explanations for increases or declines were
           given.

Hile, Ralph and Frank W. Jobes.  "Age, Growth, and Production of
           the Yellow Perch of Saginaw Bay."  Trans.  Amer.
           Fisheries Soc., 1941.   p. 102-122.

           A study of 820 fish caught in the period 1929-30.
           Length-weight ratios, growth, and sex statistics were
           reported.

Humphreys, C. R. et al.  "Shoreline classification of Bay County
           (Bulletin 21) and Tuscola County (Bulletin 22), Michi-
           gan."  Dept. Res. Devel. Agricultural Exp. Station,
           Michigan State University, East Lansing, 1958.

Johnson, James H.  "Surface current studies of Saginaw Bay, Lake
           Huron."  U.S. Dept. Interior, Fish and Wildlife Div.,
           Report #267, 1958.  84 p.

           A detailed study of the surface currents in Saginaw
           Bay primarily through the use of drift bottle studies.
           A valuable study.

Kimball, William  and Gordon Bachman.  "County and district land
           use patterns in Michigan."  Michigan State University
           Cooperative Extension Service, 1969.

           Contained useful information concerning land usage
           in the Saginaw Basin.  Segmented it into categories
           such as agricultural, industrial, urban, forested,
           navigational, recreational, etc.

Michigan State University.  "Ecological Survey of the Quinacassee
           Plant Site."   (Dr. L. Gysel, T. Reichard, and L. Reed)

           A detailed study of the ecology of the Quinacassee area.
           Examination of wildlife, topography, and fish.  In-
           cluded a limited environmental impact evaluation of a
           proposed power plant.

Michigan Stream Control Commission.  "Saginaw Valley Report." 1937.  156p,

           At the time a very comprehensive study of the bay.
           Included brine discharge data and valuable chloride
           concentration charts.  Also included color, turbidity,

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                              127
           and odor information.

Michigan Water Resources Commission.   "Report on Bacteriological
           Quality of Michigan Surface Waters Along the Great
           Lakes Coastline."

           Extensive WRC data on the coliform concentrations at
           various stations within the Saginaw Basin.

Michigan Water Resources Commission,  Department of Natural Resources,
           Lansing, Michigan.  Biologic Studies.

           The following studies are typically only a few pages
           in volume and represented very limited sampling.  They
           are listed here, without annotation, in alphabetical
           order according to their major receiving watershed.

           "Taint studies on Coho Salmon Returning to the Cass
           River, Fall 1972."

           "Biological Investigations of Hughes and Lake Drains
           and Brent Run, July 11 and October 16, 1972."  Flint
           River.

           "Biologic Investigations of Thread Creek, Flint, Michi-
           gan, July 13, 1972."

           "Biological Investigations on Gilkey Creek, Flint,
           Michigan, August 22, 1969 and July 11 and 13, 1972."

           "Biological Investigations of Carmen Creek,Flint,
           Michigan, July 13, 1972."

           "A Continuous Flow Bioassay and Cage Fish Study of
           Fisher Body Coldwater Road Plant Effluent, Flint,
           Michigan, November 27 and December 4, 1972."

           "A Continuous Flow Bioassay of the Hickory Street
           Storm Sewer Discharge, Flint, Michigan, December 11-15,
           1972."

           "Biologic Survey of the Pine River in the Vicinity of
           Alma  and St. Louis, 1967 and 1970."

           "Biologic Survey of the Pine River above Alma to
           Determine the Effects of Pollution.  May  31, 1955."

           "Continuous Flow Bioassay of the Total-Leonard Refinery,
           Alma, Michigan.  October 9-13, 1972."  Pine River.

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                              128
            "Biologic Investigations of C. K. Eddy Creek, West
            Branch, Michigan.  August 1, 1972." West Branch of
            Rifle River.

            "Biologic Field Studies Conducted on Sebewaing Bay,
            Fall, 1970."

            "Sebewaing Bay, Fish Mortality, March 28, 1957."

            "A Caged Fish Study on Toxicity of Intermittently
            Chlorinated Condensor Cooling Waters at Consumers
            Power Company's J. C. Weadock Power Plant, Essexville,
            Michigan.  December 6-10, 1971."

            "Report on the Fish Mortalities Observed at Kearn-
            Weadock Power Plant During Week of December 6-10, 1971."

            "Fish Off-flavor Problems in Saginaw Bay."

            "Caged Rainbow Trout Taint Studies in the Saginaw River
            Watershed October-November 1972."

            "Taste Test of Fish from Saginaw Bay, February 27-28,
            1968."

            "Fish Tainting Problems in Saginaw Bay, Winter of 1962-
            1963."

            "Taste Test of Fish from Saginaw Bay, May 12,  1965."

            "Taste Test of Fish from Wild Fowl Bay Area of Saginaw
            Bay, January 26, 1968."

            "Waterfowl Mortality Sebewaing Fish Point Area, late
           August-September 1962."

            "Caged Rainbow Trout Taint Studies in Saginaw River
           Watershed October-November 1972."

            "Report on Fish  Mortality in the Tittabawassee River
           below Dow Chemical, July 27, 1971."
Michigan WRC, DNR
           The following are comprehensive studies performed within
           the Saginaw Bay Basin.  They are again listed alpha-
           betically according to their receiving stream or bay.

           "Oxygen Relationships of Cass River, 1960."

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                   129
   A study of the Cass River between Frankenmuth and
   Bridgeport describing the polluting sources, hydrology,
   geology, BOD, D.O., and oxygenation and deoxygena-
   tion relationships.

"Oxygen Relationships in the Cass River."

   A 1968-1970 study very similar to the 1960 study.
   This report emphasized the Cass River downstream
   from Caro, Michigan.

"Chippewa River Water Quality Study."

   A 1968 study of the river in the vicinity of Mt.
   Pleasant.  It included discussions of hydrology,
   geomorphology, land use, waste discharges, and
   pollutional sources, and surveys of D.O., BOD,
   coliform densities, nutrient concentrations, etc.

"Water Resource Conditions and Uses in the Flint River
Basin."

   A 1956 report including information on population,
   hydrology, and water uses, such as recreation,
   navigation, water supply, power, etc.

"Water Quality Study, Flint River Tributaries."

   A 1970 report on the major tributaries to the Flint
   River, Gilkey Creek, Swartz Creek, Carinan Creek,
   and Thread Creek.  It includes discharge informa-
   tion as well as physical, chemical, and biological
   water quality data.

"Water Quality Study of the Flint River."

   A 1970 report describing sources of waste, hydro-
   logic conditions, dissolved oxygen and BOD observa-
   tions, bacterial densities, nutrient concentrations
   and limited biologic investigations.

"Pine River Water Quality Study."

   A 1967-1970 survey of the Pine River documenting
   geographical considerations, waste discharge infor-
   mation, and water quality data.  Measurements were
   taken of D.O., BOD, nutrient concentrations,
   various physical and chemical parameters, and
   coliform.

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                   130
 "Results of a study of the Bottom Fauna of Saginaw
 Bay, July 25 and 26, 1953."

   A survey of 19 stations in Saginaw Bay, documenting
   benthic fauna.  A breakdown was given of percentages
   of clean facultative and tolerant species.

 "Results of a Biologic Survey of Saginaw Bay, July 16,
 17, 1954."

   Fifteen bay stations were sampled for benthic fauna,
   species composition was evaluated.

 "Results of a Biologic Survey of Saginaw Bay, June 24,
 1955."

   Nineteen stations were sampled for benthic fauna.
   Comparative analysis was made to the 1954  and 1953
   studies.

 "Saginaw Bay Biologic Survey, July-August 1965."

   Forty-three statipns were sampled for bottom
   organisms.  Species composition and comparisons
   to past studies were reported.  Overall a thorough
   study.

 "Water Quality Study of the Saginaw River, July-October
 1965."

   A report detailing the hydrology of the river,
   its sources of waste, oxygen profiles and predictions,
   various physical and chemical parameters, and limited
   biological investigations.

 "Biological Survey of Sebewaing Bay, September 1970-
May 1971."

   Included investigations of fish populations, benthic
   animals, artificial substrate studies, sediments,
   and sources of waste to the bay.

 "Water Resources Conditions and Uses in the Shiawassee
River Basin."

   A 1963 report including discussions of geography,
   hydrology, water use and management, floods and
   flood control and low flow augmentation.

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                              131
           "Oxygen Relationships in the Shiawassee River."

              A 1968 study detailing basin descriptions, waste
              assimilation of the river, effects of pollutants,
              and deoxygenation relationships.

           "Water Resource Conditions and Uses in the Tittabawassee
           River Basin."

              A 1960 report dealing primarily with land and water
              uses within the basin.

           "Biologic Survey of the Tittabawassee River 1971-1972."

              A thorough study of the biologic communities of the
              Tittabawassee.  Examines fish,  benthos, phytoplankton,
              periphyton, rooted aquatics, and toxic materials
              concentrations.

Michigan WRC DNR Industrial Waste Water Surveys.

           Generally a one or two day survey  of an industrial
           discharger.  The reports are typically short.  They
           are listed alphabetically according to the receiving
           tributary.

           Nestles Co. Inc.  June 6-7, 12-13,  1972:  Cass River.
           Michigan Sugar Co.  November 13-15, 1972:  Cass River.
           Ferro Manufacturing Corp.  June 12-14, 1973:  Chippewa
              River.
           Metal Dynamics Inc.  June 6 and 13, 1972:  Flint River.
           Anderson-Safeway Guardrail.  August 28-30, 1972:  Flint
              River.
           Buick Motor Division.  June 13-14,  1972:  Flint River.
           Chevrolet Engine Plant.  May 2, June 6-8, 1972:  Flint
              River.
           Fisher Body Div. GMC.  May 2, June 6-8, 1972:  Flint River,
           Fisher Body Div. GMC.  August 28-30, 1972:  Flint River.
           General Motors Parts Div.  April 19-21, 1972:  Flint River.
           Kraft Foods.  May 17, 18, 19, 1972:  Pinconning River.
           Magline Corp.  April 11-12, 1972:   Pinconning River.
           Magline Corp.  March 27-28, 1968:   Pinconning River.
           Alma Travelodge.  November 20, 21,  22, 1972:  Pine River.
           Michigan Chemical Co.  August 28-September 1, 1967:
              Pine River.
           Michigan Chemical Co.  September 8-10, 1970:  Pine River.
           Chevrolet Metal Casting.  April 3-5, 1972:  Saginaw River.
           Monitor Sugar Co.  February 11, 12, 16, 17, 1970:   Saginaw
              River.

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                              132
           Monitor Sugar Co.   December 11-12,  1968:   Saginaw River.
           Michigan Sugar Co.   October 21-24,  1968:   Saginaw River.
           Michigan Sugar Co.   December 20,  1966:   Saginaw River.
           Chevrolet Parts Div. CMC.   November 30-December 1, 1971:
              Saginaw River.
           Michigan Producers  Dairy.   August 20-21,  1969:   Sebewaing
              River.
           Michigan Sugar Co.   October 12-15,  1970:   Sebewaing River.
           Michigan Sugar Co.   January 6-8,  1970:   Sebewaing River.
           Ford Autolite Division.  December 7-9,  1971:   Shiawassee
              River.
           American Record Pressing Co.  December  8-9,  1971:  Shia-
              wassee River.
           Dow Chemical Co. April 16-18, 1968: Tittabawassee River.

Michigan WRC DNR.  "Interim Water Quality Management Plan for the
           Saginaw River and Huron Western Shore Minor Basins."
           April 1971.

           A report primarily  concerned with resource management
           and planning.  It did include hydrologic, geographic,
           and water quality information.  Described in detail
           land usage and population patterns.

Michigan WRC DNR.  Miscellaneous Water Quality Reports.   Listing
           alphabetically according to major tributaries.

           "Effects of Earl Johnson Cattle Feedlot on Water Quality."
           April 10 and 19, 1969.  Flint River.

           "PCB's in Saginaw River Basin."  January 1973.

           "A survey of chlorine concentrations in the J. C.
           Weadock Power Plant Discharge."  Saginaw River.

           "Water Temperature Survey of the Saginaw River Mouth."

           "Report of Caustic Spill into the Tittabawassee River
           by Dow Chemical Company, August 13, 1971."  Tittabawassee
           River.

Michigan WRC DNR:  Monthly operating reports on discharges  to the
           Saginaw Basin.

           A computer listing of all the direct dischargers  in
           the basin and the discharge stipulations for which
           they must comply and report on monthly according  to  the
           NPDES system.

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                              133
Michigan WRC DNR:  Municipal Dischargers.

           A listing for the Bureau of Water Management enumera-
           ting all municipal dischargers and the extent of WRC's
           records concerning their effluent.

Michigan DNR, WRC.  "The Water Resources of Lower Lake Huron
           Drainage Basin."  May 1968.

           An overview of the regions water uses.  Hydrology,
           geology, water and land usage and general water quality
           were discussed.  Various rivers were discussed indiv-
           idually with regard to water quality.

Michigan DNR WRC.  "Water Resource Uses Present and Prospective
           for Lake Huron."

           An overview of the existing water resources and their
           uses.  Basic problems were identified and water quality
           standards were proposed.  Plans for implementation
           were also included.

Michigan DNR WRC.  "Water Quality Monitoring Program of Michigan
           Waters along the Great Lakes Coastline."  1963-1969.

           A complete listing of the water quality measurements
           made on the Great Lakes tributaries.  Included physical,
           chemical, and hydrological data.

Shneider, J. C., Hooper, F. H. and Beeton, A. M.  "The Distribu-
           tion and Abundance of Benthic Fauna in Saginaw Bay,
           Lake Huron."  Proc. 12th Conference on Great Lakes
           Research, 1969. p.  80-90.

           A very good analysis of a 1956 survey of benthic re-
           sources of the bay.  Species composition, distribution,
           and abundance are discussed and compared with other
           benthic studies.

Schuytema, G. S., and Powers, R. E.  "The Distribution of Benthic
           Fauna in Lake Huron." GLRD, University of Michigan,
           Pub. #15, 1966.   P-  155-163.

           Presents the results of a 1965 survey of Lake Huron of
           which 24 stations were in Saginaw Bay.  Identified all
           species found.  Emphasized oligochaete and amphipod
           distribution in Saginaw Bay.

Tarrant, William J.  "Water Quality Review with a History of Water
           Supplies."  Prepared for Saginaw Midland Water System

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                              134
           Research Advisory Board, 1972.

           A collection of maps, charts, and papers concerned
           with the Saginaw Midland water supply and uses.

Teter, Harold E.  "The Bottom Fauna of Lake Huron."  Trans. Amer.
           Fisheries Soc. Vol. 89  (2), 1960.  p. 193-197.

           The examination of 63 bottom samples from 1952 and 1956
           surveys of Lake Huron.  Included only the very outer
           limits of Saginaw Bay.

Tharratt, Robert C.  "Food of Yellow Perch in Saginaw Bay,  Lake
           Huron."  Trans. Amer. Fisheries Soc.  Vol 88, 1959. p.  330-331,

           Stomach analyses were performed on 241 fish from 4
           stations in Saginaw Bay.

University of Michigan, Great Lakes Research Division.  "Limno-
           logical Surveys of Lakes Michigan, Superior, Huron,
           and Erie."  Pub. #17, 1973.

           A wide encompassing survey of four of the Great Lakes.
           It included six stations in Saginaw Bay and often
           valuable information on phytoplankton and zooplankton.

U. S. Army Corps of Engineers.  "Saginaw River."  A House Document
           from February 23, 1956, 84th Congress, 2nd session.

           Primarily concerned with flood and navigational prob-
           lems within the Saginaw River basin.  Did not address
           itself to water quality conditions.

U. S. Army Corps of Engineers.  "Preliminary Examination Report
           on Property Damage on the Great Lakes Resulting from
           Changes in Lake Levels."  1952.

U. S. Army Corps of Engineers.  "Summary of Environmental Consid-
           erations, Great Lakes-St. Lawrence Seaway Navigation
           Season Extension, Waste Heat Utilization Demonstration."
           U. S. Army Corps of Engineers, District of Detroit,
           Michigan,  1973.

           A report dealing primarily with the environmental impacts
           that might precipitate if the ice-free navigational
           season was extended through the use of power plant
           thermal discharges.  The navigation program is designed
           for the St.  Lawrence-Great Lakes system but the demon-
           strations     included only a small area in the
           Saginaw Bay-Saginaw River system.  The environmental

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                               135
            considerations were usually qualitative, general,
            and brief in content.  The report also included al-
            ternatives and a brief description of the Saginaw
            environment.

U. S. Dept. of the Interior.  "National Estuary Study Vol. 3."
            Fish and Wildlife Service, 1970.

            Includes a very good overview of activities and
            existing conditions in Saginaw Bay.

U. S. Dept. of the Interior, Bureau of Outdoor Recreation.
            "Preliminary, Water Oriented Outdoor Recreation,
            Lake Huron Basin."  October 1967.

            Giver an overview of the basin environment and uses
            emphasizing water supply and water quality effects on
            recreational uses.

U. S. Dept. of the Interior, Fish and Wildlife Service.  "Fish
            and Wildlife as Related to Water Quality of the Lake
            Huron Basin."  1969.

            Was a good source of information concerning the
            fish resources of Saginaw Bay.  It also contained
            some water quality data for tributary rivers.

U. S. Dept. of the Interior Geologic Survey.  "Water Resources
            Data for Michigan.  Part 1:  Surface Water Records,
            Part 2:  Water Quality Records."  1970.

            Contains valuable flow information for the tributary
            system of the Saginaw Basin.

U. S. Lake Survey.  "Great Lakes Pilot."  1973.

            A report concerned primarily with navigational consid-
            erations .

U. S. Lake Survey.  "Lake Huron Limnological Data."  1966.

            Included sampling from four stations in theouter
            Saginaw Bay.   Reported nutrient, chemcial, transpar-
            ency,  and thermal data.

U. S. Transportation Dept.:  Environmental Impact Statement for
            the Reconstruction of 1-75 Zilwaukee Bridge Over the
            Saginaw River."

Velz, Clarence J., and Gannon, John  J.  "Drought Flow Characteristics
            of Michigan Streams"  Dept. of Environmental Health,
            University of Michigan,  1960.

            A compilation and evaluation of the available low flow
            records of Michigan streams.   Precipitation,  temperature,

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                               136
            and lake level data were also presented in the report.
            Overall a comprehensively done report.

Wood, Leonard E.  "Bottom Sediments of Saginaw Bay, Michigan."
            Journal of Sedimentary Petrology, Vol. 34, No. 1, 1964.
            p. 173-184.

            A study of 61 bottom samples from 1956.  The sediments
            were analyzed primarily for size and mineral content.

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                               137
                     Unreviewed References


Alexander, H. C. and Teal, J. L.  "Observations made on the Pine,
            Chippewa, and Tittabawassee Rivers, July 17-19, 1962."
            Dow Chemical Co. Report, Midland Division, 1962.

Alexander, H. C.  "Biological Survey of the Pine, Chippewa, and
            Tittabawassee Rivers."  Dow Chemical Co. Report,
            Midland Division, 1962.

Alexander, H. C.  "Bottom Fauna Survey, Saginaw Bay, June 15-16,
            1962."  Dow Chemical Co. Report, Midland Division, 1963.

Alexander, Howard C.  "Saginaw Bay biological survey, July-August
            1965."  Dow Chemical Co. Report, Midland Division, 1967.

Canadian Center for Inland Waters:  Biological and chemical
            water quality data available from their various Great
            Lakes Cruises.

Duddles, Glenn A.  "Biological Survey of the Pine, Chippewa,
            and Tittabawassee Rivers."  Dow Chemical Co.  Report,
            Midland Division, 1968.

Zillich, J. A.  "Fish Taint and PCB's in the Saginaw River Water-
            shed."  Dow Chemical Co. Report, Midland Division, 1973.

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