WATER QUALITY INVESTIGATIONS
LAKE MICHIGAN BASIN
BIOLOGY
A technical report containing "background data
for a water pollution control program.
January 1968
UNITED STATES DEPARTMENT OF THE INTERIOR
FEDERAL WATER POLLUTION CONTROL ADMINISTRATION
Great Lakes Region Chicago, Illinois
-------
icwnr
-------
TABLE OF CONTENTS
SUBJECT PAGE
FOREWORD ii
SUMMARY AND CONCLUSIONS 1
BIOLOGICAL EFFECTS ON WATER USES 3
MID-LAKE AREA RESULTS 7
INSHORE AREA RESULTS 13
SPECIFIC AREAS - BOTTOM ANIMALS lk
SPECIFIC AREAS - ALGAE 21
APPENDIX 30
METHODS 31
TABLES 33
-------
FOREWORD
The study of the biology of the Lake Michigan Basin was
conducted under the administrative guidance of H. W. Poston,
Regional Director, Great Lakes Region, FWPCA. Sample collections
and analyses and data compilation and organization were made by
regional personnel. Final draft of the report was prepared by
biologists of the Technical Advisory and Investigations Branch,
FWPCA, Cincinnati, Ohio.
ii
-------
SUMMARY AND CONCLUSIONS
1. The biota of the mid-water area of Lake Michigan reflects an
unpolluted environment. Free floating algal populations
were less than 500 per milliliter. Pollution-Sensitive scuds
predominated in the bottom associated organism population.
Sludgeworm populations were less than 1,000 per square meter
and midges were principally of the clean water variety.
2. Extensive inshore areas of pollution totaling 3,U?5 square
miles were found along the entire southern perimeter of Lake
Michigan specifically Milwaukee, Racine and Chicago-Calumet
and in Green Bay. The loss of the Green Bay fly, a fish
food organism, and other detrimental pollution associated
conditions have impaired commercial fishing in Green Bay.
Swimming beaches have been closed in Milwaukee, Chicago
and other areas when large mats of foul smelling algae have
been deposited on the beaches. Aesthetic values associated
with water have been impaired by algae on many occasions.
Short filter runs and taste and odors resulting from high
-------
phytoplankton populations have increased the cost of
water treatment at Green Bay, Milwaukee, Kenosha, Chicago,
and other cities.
3. Other more localized inshore areas of pollution totaling
350 square miles resulted in increased sludgeworms and
free floating algal populations offshore from: Manitowoc,
Sheboygan, Port Washington, Benton Harbor, South Haven,
Saugatuck, Grand Haven, Muskegon, Ludington, Manistee, and
Manistique.
h. Pollution of inshore areas: supported pollution-tolerant
sludgeworm populations exceeding 1,000 per square meter;
suppressed gamefish food organisms; supported nuisance
algal populations exceeding 500 per milliliter and as high
as 20,000 per ml. in Green Bay; produced dense growths
of attached algae in shallow water areas that break loose
and become deposited on swimming beaches. Soluble phos-
phate (POi ) concentrations averaged O.OU mg/1 with values
as high as 5.0 in these areas. These concentrations
exceed the adopted standard of an annual average total
phosphate (PO. ) of 0.03 mg/1 and a single daily average
or value of 0.0*4- mg/1.
-------
BIOLOGICAL EFFECTS ON WATER USES
The biological examination of waters and bottom materials
incorporates both a qualitative determination of the kinds of
organisms present and a quantitative estimate of their numbers
or bulk. This information aids in the interpretation of physical
and chemical analyses, indicates pollution by wastewaters, de-
termines the progress of self-purification within the waterways,
assists in the limnological study of the environment, measures
damages inflicted on aquatic life and water use potentials, and
indicates impact of nuisance organisms on water uses.
Suspended microscopic plants (algae) are the primary con-
verters of light energy to organic matter; they are the original
source of most of the food that nourish fish and other aquatic
animals. Changes in the physical and chemical properties of
the water affect both algal quantities and species composition.
When the quantity of fertilizing nutrients increases, the
number of algae will increase and the species composition will
change. Dense green algal populations reduce the aesthetic
-------
values of a water and interfere with water uses such as boat-
ing and swimming. Windrows of dead and odoriferous decaying
algae are nuisances and obstruct uses at beaches and surround-
ing lands. Changes in both the concentration and relative
composition of the fertilizing material produce detectable
changes in the species composition of the algal populations.
High concentrations of phosphorus favor the blue-green algae
which are capable of using nitrogen from the atmosphere as
a source of nitrogenous nutrition; these algae are particularly
obnoxious because they are more buoyant than other forms thus
tending to form windrows more readily and produce especially
obnoxious "pigpen" odors because of chemical compounds peculiar
to them.
Bathing beaches have been closed for extensive periods
near Milwaukee, Chicago and other localities because of rotting
foul-smelling algae and dead fish, and threats to public health
from water contaminated by sewage. A seemingly inexhaustible
supply of algae that has washed ashore in recent years has
defied maintenance attempts to keep some beaches usable during
the recreational period. Bathers and sun-bathers must travel
farther to enjoy their sport. The aesthetic beauty of Lake
Michigan has been severely impaired.
-------
Excessive quantities of algae in Lake Michigan have
caused short filter runs in water treatment plants. When the
runs are shorter than 20 hours, the result is a loss in
revenue because of loss of plant capacity and the use of
larger amounts of wash water. Kenosha, Wisconsin obtains its
water supply from an intake pipe extending 4,200 feet into Lake
Michigan to a depth of 30 feet and has experienced three-hour
filter runs in recent years along with taste and odor problems.
Because algae and other microorganisms are implicated in both
of these water supply problems, Kenosha in 1961 installed four
microstrainers at a cost of $330,000 to reduce the number of
microorganisms. At this time Kenosha was receiving as much as
1|-50 pounds per day of wet algae through the water intake pipe.
Following microstrainer installation, that resulted in 90 per-
cent algal removal, taste and odor problems disappeared and
filter runs increased to an average of k& hours. Problem
algae were: Stephanodiscus, Tabellaria, Asterionella, Synedra,
and others.
At Green Bay, Sheboygan, Milwaukee, Waukegan, Evanston,
Chicago, Gary-Hobart, Michigan City, Benton Harbor, Holland,
Grand Rapids, and Musekgon, 37 percent of filter runs were
less than 20 hours in 1961.
-------
Bottom animals serve as a vital link in the aquatic food
web by converting plant food into animal food for predatory
fishes. Changes in numbers of bottom animals and in composi-
tion of the bottom-animal community produce changes in the fish
population. For example, a community consisting predominantly
of burrowing worms favors a community of fishes such as carp
and suckers that root for their food. An increase in worms is
a product of an increased food supply from sedimentation of
organic waste materials or dead algae. Changes in the kinds and
numbers of bottom animals are effects that are frequently a
product of pollutants; these changes result in damages to de-
sirable aquatic organisms, and may produce increased numbers of
undesirable aquatic organisms that interfere with and reduce
the uses that can be made of the waters.
Environmental changes resulting from pollution eliminated
the burrowing mayfly (Green Bay fly) from major sectors of
Green Bay in recent years. Concurrently commercial fishing
was severely impaired, thus affecting another water use by
disrupting the aquatic food web.
-------
MID-. LAKE AREA RESULTS
The deep-water areas of Lake Michigan are presently un-
affected by the pollution observed in many areas closer to
shore. Soluble phosphate (PO.) averaged 0.02 milligrams per
liter (mg/l) in deep water areas with some values as high as
O.lk mg/l. inshore areas averaged 0.04 mg/l PO. with values as
high as 5.00 mg/l. Adopted water quality standards for Lake
Michigan open water and shore water limit annual average total
phosphate (POO to 0.03 rag/1 and a single daily average or
value to 0.0^ rag/1. Obviously these standards are now exceeded
in some areas and high nutrient concentrations are reflected
in increased biological growths. Inorganic nitrogen averaged
0.19 milligrams per liter in deep-water (ranging as high as
1.15) compared to 0.2? milligrams per liter inshore (ranging
as high as 2.2 near Milwaukee). The distribution of populations
of benthic animals and phytoplankton generally reflects the
pattern of distribution of soluble nutrients.
With one exception, the population of bottom organisms
decreased with increasing depth (Table l). In the deepest
-------
8
area (260-269 meters) there was an increase in the population
2
of all organisms to 5,000 per m ; this is characteristic of
organism population distribution in many deep lakes. Scuds
of the genus Pontoporeia, are pollution-sensitive organisms;
they were the predominant bottom-associated organisms in areas
not greatly influenced by organic sediments.
The population of scuds in much of the deep central basin
numbered less4 than 1,500 per square meter (Figure l). There
is a combination of depth dependent factors such as sediment
types and nutrient content that limits scud populations in
depths greater than 50 meters. In the deep central areas of
the lake sludgeworm populations numbered less than 1,000 per
square meter. This relatively low population of sludgeworms
as shown in Figure 2 indicates an unpolluted environment. The
midge larval population in the central section of Lake Michigan
averaged 37 per square meter and was composed of Bk percent
clean-water species and no pollution-tolerant species with the
remaining being of variable tolerance. This further indicates
the unpolluted condition of the sediments of the central basin.
The deep-water areas of Lake Michigan supported planktonic
algal communities of low population density that generally
ranged from 100 to 300 organisms per milliliter (Figure 3)«
Conversely, nutrient-enriched inshore areas supported larger
-------
populations of phytoplankton, generally numbering more than
500 organisms per milliliter.
For many years, the planktonic algae of Lake Michigan
have been dominated by the genera Tabellaria, Asterionella,
and Synedra. These forms are found in nonfertile lakes. How-
ever, pollution of Lake Michigan has caused Cyclotella and
Stephanodiscus to become the predominant forms in most samples;
even in samples in which Asterionella, Tabellaria and Synedra
predominated, Cyclotella and Stephanodiscus usually were
abundant,. Table 2 lists the genera of phytoplankton most
commonly encountered in Lake Michigan waters.
-------
NORTH
POLLUTED , IOOO- 2OOO/m 2
VERY POLLUTED, over 2OOO/m2
FIGURE I
GREAT LAKES - ILLINOIS
RIVER BASINS PROJECT
SLUDGEWORM POPULATION
NUMBER PER SQUARE
METER
U.S. DEPARTMENT OF THE INTERIOR
FEDERAL WATER POLLUTION CONTROL ADMIN
Gr«ot Lok«» Rtgtwi Chlcogo ,llllnoi«
-------
NORTH
GREAT LAKES - ILLINOIS
RIVER BASINS PROJECT
SCUD POPULATIONS
NUMBERING GREATER THAN
I500 PER SQUARE METER
U S DEPARTMENT OF THE INTERIOR
FEDERAL WATER POLLUTION CONTROL ADMIN
Great Lakes Region Chicago , Illinois
-------
NORTH
:;;-::Traverse
;;;;!;•••: City
:MICH.
IND.
Michigan
iiiCity
f I 0-300/ml.
300-500/ml.
over 500/ml.
MILE
25
d
GREAT LAKES - ILLINOIS
RIVER BASINS PROJECT
PHYTOPLANKTON
POPULATIONS
NUMBER PER MILLILITER
SPRING 1962
U.S. DEPARTMENT OF THE INTERIOR
FED. WATER POLLUTION CONTROL ADMIN-
Great Lakes Region Chicago , III.
-------
INSHORE AREA RESULTS
Massive areas along the perimeter of the southern half
of Lake Michigan are polluted to such an extent that large popu-
lations of pollution-tolerant sludge-worms occur. The 2,100 square
mile area classified as polluted in Figure 2, extending from
Chicago northeastward around the southern tip of Lake Michigan,
results from organic nutrients discharged by the large metropolitan
areas bordering the lake. Lake sediments supporting populations of
sludgeworms greater than 100 per square foot (approximately 1,000
per square meter) are considered polluted. Other areas that have
polluted lake bed sediments occur in Green Bay, adjacent to the shore-
lines of Manitovoc, Sheboygan, Port Washington to Waukegan, and
between Ludington and Manistee. Despite generally higher sludge-
worm densities in inshore areas, the average number of organisms was
depressed in a narrow band along the Chicago and Indiana shoreline.
This was probably a result of wave action in the inshore areas which
did not allow the settling of fine organic particles.
-------
SPECIFIC AREAS - BOTTOM ANIMALS
Inshore areas receiving municipal wastes supported increased
populations of pollution-tolerant bottom animals such as sludgeworms.
The principal bottom material found at the southern tip of Green Bay
was organic sediment, a favorable habitat for sludgeworms and blood-
worms which were the predominant organisms. Total populations of
bottom-dwelling organisms in 19^2 and 19^3 averaged 1,960 organisms
per square meter near the mouth of the Fox River and gradually
decreased to 500 or less ten miles out into the bay (Table 3). Bur-
rowing mayflies were not found. Some pollution-sensitive snails
occurred about five miles from the mouth of Fox River.
Twenty-eight square miles of lower Green Bay are classed as
polluted; large number of sludgeworms inhabit this area. The number
of sludgeworms was greater than the number of scuds in this area;
this indicates a pollution by organic wastes. The population of
bottom organisms inhabiting the area influenced by the Fox River is
affected adversely, altered in composition, and does not supply the
fish food potential necessary for maximum water use.
The area of Green Bay affected by the Oconto River discharge
was degraded, as indicated by the types of benthic animals; only a
few pollution-sensitive organisms were found within two miles of the
river mouth. Benthic populations in 1962 and 1963 were highest
near the mouth of the Oconto River with populations of 1,020 organisms
-------
15
per square meter. Five miles from the mouth, populations had de-
creased to about 500 benthic animals per square meter; bloodworms pre-
dominated. A few pollution-sensitive scuds existed less than two
miles from the mouth. The discharge of rich organic wastes from the
Oconto area contributes to the enrichment and degradation of Green
Bay.
Polluted conditions were also indicated in the vicinity of
the Menominee and Peshtigo RiVers. In 1962 and 1963 there were
fewer benthic organisms in the vicinity of the Menominee and the
Peshtigo River outlets than there were in southern Green Bay. A
benthic population of 800 per square meter, which consisted mainly
of pollution-tolerant bloodworms and sludgeworms, was found at the
mouth of the Peshtigo. Twenty-five hundred organisms per square
meter, mostly sludgeworms and bloodworms were found near the mouth
of the Menominee. Rapid improvement in conditions, in a predominantly
sandy bottom, was shown by 1,300 scuds per square meter occurring
about three miles from the mouth of this river.
The sand and clay bottom deposits in the near vicinity of Mani-
towoc and Twin Rivers supported a population of bottom organisms
predominated by scuds because organic materials do not settle in this
wave-swept area. Populations of 5,000 to 10,000 benthic animals per
square meter, mostly sludgeworms, were collected four miles east of
the Manitowoc River, indicating severe pollution caused by the deposition
-------
16
of organic matter. A 228 square mile area off shore from the town
of Manitowoc is classified as polluted because the sediments sup-
ported more than 1,000 sludgevonns per square meter indicating
an organic enrichment of the lake bed.
The Sheboygan River outlet area was found to be degraded
one mile from shore. Samples showed more than fifty percent sludge-
worms out of a total of 7,000 organisms per square meter. In an 88
square mile area, sludgeworms numbered more than 1,000 per square
meter thus indicating polluted conditions. Improved conditions
were indicated by a predominance of pollution-sensitive scuds five
miles from shore.
Degraded biological conditions in the Milwaukee River out-
let area in 19o2 and 19^3 were indicated by the population of
bottom organisms. The harbor was almost devoid of pollution-
sensitive organisms. Populations of sludgeworms as high as 150,000
per square meter were found within Milwaukee harbor and further
pollution was indicated seven miles from the river outlet by a pre-
dominance of pollution-tolerant organisms.
Fifty-six percent of the midges collected in the area from
Port Washington to Kenosha were of the pollution-tolerant group.
The entire 1,350 square mile shore area from Port Washington to
Waukegan is classified as polluted with 1,100 square miles of it being
extremely polluted. The pollution-sensitive scud population is depres-
-------
17
sed in the area off Milwaukee. The existing bottom-animal popu-
lation indicates organic pollution and a decreased fish food supply.
The deposition of organic materials in shore areas from Port
Washington past Chicago to Benton Harbor is influenced by currents
that flov parallel to the shore and reverse with the wind direction.
These currents deposit organic materials in a band around the
southern end of Lake Michigan.
The Root River (Racine) area of Lake Michigan was biologi-
cally degraded. Pollution-tolerant forms were very abundant near
the mouth of the river and predominated five miles out into the
lake. A benthic population averaging l8,5oO per square meter (up
to 97jOOO per square meter) was found near the mouth of Racine
Harbor. Ninety-six percent of these organisms were pollution-
tolerant sludgeworms.
An examination of bottom samples in the harbor areas along
the southern shore indicated that waste discharges were and are such
that they contribute to a bottom deposit inhibitory to the establish-
ment of large populations of bottom animals. Some of these deposits
appeared to contain significant quantities of oil, grease and allied
petroleum waste. The degradation of bottom organisms in the southern
end of Lake Michigan extended out as far as twenty miles. The total
area degraded by organic wastes discharged from the Chicago-Calumet
area is 2,100 square miles as indicated by the increased population
-------
18
of sludgeworms. Offshore from the Calumet area streams, pollution-
tolerant organisms averaged 2,700 to ^,300 per square meter and there
were only a few pollution-sensitive organisms. The depression of
the population of clean water associated scuds results from toxic
wastes being discharged from the Calumet area (Figure l). To the
north, along the Chicago shoreline, pollution-tolerant organisms
averaged about 10,000 per square meter and pollution-sensitive forms
averaged 500 per square meter indicating severe pollution.
The inshore areas of Lake Michigan from Calumet Harbor to
Burns Ditch were and are extensively degraded biologically in degrees
ranging from severe near Indiana and Calumet Harbors to less severe
near Burns Ditch. Evidence that wastes from the Calumet area are
deposited in the lake was found in the bottom materials and the odors
of dredgings from this area of Lake Michigan. Petroleum odors were
often detected in bottom muds. Pollution-tolerant organisms, mostly
sludgeworms and sphaeriid clams, predominated in the areas along the
southern shore.
Continuing along the south shore of Lake Michigan in a counter-
clockwise direction, the southern tip of Lake Michigan reflected the
effects of pollution in the vicinity of Trail Creek and the Galien
River (Michigan City-New Buffalo area). Many of the bottom samples
collected in the vicinity of the Galien River and Trail Creek were
predominantly sludgeworms with populations of 5,000 to 10,000 benthic
-------
animals existing a few miles from shore. One sample collected
two miles northeast of Trail Creek consisted of fine black sand and
supported a population of over 26,000 organisms per square meter—
90 percent of which were sludgeworms. Many of the samples collected
about four miles from shore were devoid of pollution-sensitive organ-
isms. These conditions represent sustained degradation of the waters
in this area through the discharge of wastes via Trail Creek and the
Galien River.
Sludgeworms predominated within the South Haven Harbor. The
bottom habitat emitted a sewage odor. The discharge of organic
materials from the communities of South Haven, Saugatuck, Grand Haven
and Muskegon results in a band of organically enriched sediments
five miles off shore. This organically degraded lake bed supports a
sludgeworm population exceeding 1,000 per square meter and a midge
population that numbered 6l per square meter and was made up of jk
percent pollution-tolerant forms.
Organic enrichment in the area immediately adjacent to the out-
let of White Lake at Whitehall was evident during 19^2 to 1963.
Almost 1,000 midges per square meter, mostly pollution-tolerant
Tendipes plumosus and riparius, were found at that station.
Water quality conditions appeared good near the Pentwater
and Little Sable Point areas. The bottom community in the sandy area
off the Pentwater River, consists of mostly midges, scuds and sphaeriid
clams, from 1,000 to 7,000 per square meter.
-------
20
Water quality also appeared good near Little Sable Point.
The benthic community consisted of about 5,000 organisms per square
meter with substantial numbers of clean water scud.
The benthic population around the mouth of the Pere Marquette
River was composed of less than 500 pollution-tolerant sludgeworms
and midges per square meter. Amphipods, from 3>000 to 6,000 per
square meter, predominated in samples collected within a two mile
radius. The Ludington Spoil Bank supported a small community that
was mostly scuds, less than 500 per square meter. The degradation
of the lake bottom was less severe out from the communities of
Ludington and Manistee in that midge populations increased to 12^
2
per m and pollution-tolerant forms comprised k6 percent of the
total number (Table 4). However, a 3°" square mile area between the
towns supported a population of pollution-tolerant sludgeworms
2
exceeding 1,000 per m .
The bottom fauna of Manistee Lake consisted mostly of
pollution-tolerant midges and sludgeworms in populations of 500 to
1,000 per square meter. Near the outlet of the lake, no organisms
were found. Lake Manistee deposits emitted sewage and petroleum
odors. In adjacent Lake Michigan, bottom animal populations were
less than 100 per square meter, although midges still predominated.
The bottom fauna (approximately 1,000 organisms per square meter) con-
sisted of over 50 percent amphipods about two miles out from the mouth
of Manistee Lake.
-------
21
No appreciable effects were noted from the Betsie River or
the City of Frankfort on the benthic fauna of adjacent areas of
Lake Michigan. Populations consisting mostly of 100 to 3,000 amphi-
pods per square meter inhabited the sandy bottom.
At the northern tip of Lake Michigan, degraded localized
conditions appeared near Manistique. Samples collected near the
Manistique River mouth indicated that benthic populations were less
than 1,000 per square meter,, Only 67 midges per square meter vere
dredged up near the harbor. The bottom was found to consist mainly
of organic matter and had a foul odor as the result of paper mill
wastes. One mile south of this area, 100 to 250 pollution-sensitive
scuds per square meter were found.
SPECIFIC AREAS - ALGAE
For several years the Chicago Park District has reported that
beaches became fouled with algae washed in from the lake. In 19^1,
the offending organism at Oak Street and Montrose beaches was found
to be Dichotomosiphon, a green filamentous alga similar in appearance to
Cladophora.. In 1962 Cladophora was the principal alga but Oedogonium
was also present. All of these organisms require a hard substratum,
or attachment surface. The windrows of algae that completely lined
the beaches became four-smelling after a few days exposure to the
summer heat. Flies and other insects covered the decaying masses.
-------
22
In July, 1963 large floating masses of Cladophora and
Mougeotia were found in southern Green Bay near the western shore.
The pollution-tolerant blue-green alga, Lyngbya, was found attached
to rocks on the bottom of Calumet Harbor in May 1963.
Phytoplankton concentrations of more than 500 organisms per
milliliter are considered excessive; they may give the water an
objectionable appearance, induce tastes and odors in domestic water
supplies, and increase the cost of water treatment. The City of
Kenosha has found it necessary to install a very expensive micro-
straining system for adequate water treatment because of excessive
algae in the raw water. Other cities that have experienced taste
and odor problems in their water supplies include Michigan City,
Gary-Hobart and Chicago.
Green Bay is an example of accelerated eutrophication in-
duced by man-made wastes. Severe oxygen depletion often occurs.
Soluble phosphate levels averaged 0.07 mg/1 as PO. and ranged as
high as 0.60 mg/1; the critical level for algal blooms is considered
to be 0.03 mg/1 as PO. . Ammonia nitrogen averaged 0.17 mg/1 while
NO -N averaged only 0.08. The highest phytoplankton populations
occurred near the mouth of the Fox River. In July 1963? total popu-
lations of 20,000 per milliliter were found. These numbers decreased
to 5,000 to 10,000 about ten miles out into the bay. The kinds of
phytoplankton in this area were mostly green flagellates, centric
diatoms and green coccoids. Blue-green forms were also found in
-------
large numbers, from TOO to 1,500 per milliliter. Light penetration
in Green Bay was greatly reduced (Secchl disc readings vere only
0.2 meters compared to 16 meters in the northern basin). Near the
mouth of the Fox River, average inorganic nitrogen values were close
to 0.5 milligrams per liter and average total soluble phosphates
were 0.20 milligrams per liter, or nearly seven times greater than
the critical level necessary for algal blooms.
The algal population near the Oconto River mouth in July
1963 averaged over 80,000 phytoplankters per milliliter and consisted
mostly of green flagellates and green coccoids. These same types
predominated in the adjacent lake area in nuisance numbers, from 1,000
to 20,000 per milliliter. The proportion of diatoms was higher in
Green Bay than in the Oconto River. Numbers of algae were consider-
ably less on the eastern shore of Green Bay, from 500 to 5,000 per
milliliter.
In spring, 1962, phytoplankton populations in excess of 1,200
organisms per milliliter were collected from the Manitowoc-Sheboygan
area (Figure 3)• This condition resulted from high soluble phosphate
levels, ranging from O.OU to 0.07 mg/1.
Milwaukee Harbor was found to be severely polluted by organic
enrichment. It is estimated that 9,300 pounds per day of total
phosphate was discharged into Lake Michigan at the mouth of the
Milwaukee River. Soluble phosphate concentrations averaged O.kh mg/1
(nearly 15 times the level of phosphates considered critical for the
-------
stimulation of algal blooms) and ranged as high as "L.k mg/1.
Adjacent water offshore averaged 0.07 mg/1. Total inorganic nitrogen
in Milwaukee Harbor averaged 1.25 mg/1 and ranged as high as 2.9^
mg/1. Adjacent areas offshore averaged 0.32 mg inorganic N/l and
ranged as high as 2.2 mg/1 total inorganic nitrogen. A Secchi disc
was visible to less than one meter in the harbor.
High phytoplankton counts in the Milwaukee area indicated
enrichment. In the fall of 1962 over 1,500 organisms per milliliter
were collected from the harbor. Generally, populations decreased
with distance from shore, from over 1,000 per milliliter to less than
100 per milliliter at mid-lake (Figure 4). Predominant genera were
Cyclotella, Stephanodisous, Tabellaria, and Asterionella.
In June of 19^3, populations of almost the same size and kind
existed both in the river mouth and harbor area, from 1,000 to 20,000
per milliliter. Centric diatoms were the predominant kinds of algae.
In spring, 19^3, phytoplankton numbered nearly 6,000 per milliliter
at the mouth of the Milwaukee River.
These biological findings reflect the deteriorated water
quality in the Milwaukee vicinity of Lake Michigan and represent the
gross pollution resulting from the domestic and industrial wastes dis-
charged in this area.
The Root River (Racine) area of Lake Michigan was severely
polluted with organic enrichment. In 1962 and 19^3 soluble phosphate
(PO, ) averaged 0.07 mg/1 and ranged as high as 0.10 mg/1. Phytoplankton
-------
I I 0-300/ml.
3OO-500/ml
ovtr 500/ml.
GREAT LAKES* ILLINOIS
RIVER BASINS PROJECT
PHYTOPLANKTON
POPULATIONS
NUMBER PER MILL I LITER
FALL 1962
U.S. DEPARTMENT OF THE INTERIOR
FED. WATER POLLUTION CONTROL ADMH4
Gr«ot Lok«» Region Chicago,III.
-------
26
samples in the fall of 1962 contained 2,229 organisms per milliliter
(Figure 4); this was one of the most dense phytoplankton populations
encountered during the fall survey and may be compared with concentra-
tions of less than 200 phytoplankton organisms per milliliter in the
mid-lake deepwater areas. Cyclotella, Stephanodiscus, Tabellaria and
Asterionella were the predominant algal forms. Melosira became the
predominant form in the summer.
The waters of Chicago Harbor, Calumet Harbor and Indiana Harbor
each contained excessive amounts of algal-stimulating nutrients. In
Chicago Harbor, soluble phosphates averaged 0.04 mg/1 and ranged as
high as 0.15 mg/1- In Calumet Harbor, soluble phosphates averaged
0.05 mg/1 and ranged as high as 0.1^ mg/1; total inorganic nitrogen
averaged 0.35 mg N per liter and ranged as high as 1.02 mg/1.
Indiana Harbor water contained an average of 0.05 mg/1 soluble phos-
phorus and ranged as high as 0.12 mg/1. Total inorganic nitrogen
averaged 1.56 mg/1 and ranged as high as 3-1^ mg/1- A concentration
of 0.30 mg/1 inorganic nitrogen is considered critical for stimulation
of algal growth in the presence of adequate phosphorus.
Phytoplankton populations in the Chicago-Calumet area remained
very dense during the period of study. In 1962, up to 1,298 organisms
per milliliter of sample were found (Figure 3)• In 1963> phytoplankton
populations increased to 2,1^3 phytoplankton organisms per milliliter.
Light penetration in the Indiana Harbor Canal was severely restricted;
a Secchi disc was not visible at one meter.
-------
27
The distribution of phytoplankton in Lake Michigan was gener-
ally influenced "by wind-produced currents. In spring, 19^2, over 500
phytoplankton per milliliter were collected from inshore waters,
beginning at the Chicago-Calumet area and continuing north up the
entire eastern lake shore (Figure 3)« By the summer of 19^2, the
current pattern had changed; phytoplankton distribution became more
random, except for high numbers of organisms (over 300 per ml) near
Chicago and South Haven (Figure 5). Fall, 19^2, phytoplankton counts
again revealed high concentrations of over 500 organisms per milli-
liter along both the southeastern and southwestern shores (Figure k).
The effects of heavy pollutional loads were evident in the
vicinity of the St. Joseph River and Benton Harbor. Soluble phos-
phate concentrations in the St. Joseph River averaged 0.2^ mg/1 and
ranged as high as 0.9^ mg/1. Total inorganic nitrogen concentrations
averaged 1.12 mg/1 and ranged as high as 3-04 mg/1. In spring, 19^2,
phytoplankton populations of 3*100 organisms per milliliter were con-
centrated in the waters just offshore from Benton Harbor (Figure 3)•
Mid-lake waters contained less than 200 phytoplankton organisms per
milliliter in spring, 1962.
Lake Michigan waters in the vicinity of Grand Haven, Mighican
consistently exhibited the effects of pollutional nutrient loadings.
The Grand River, which enters the lake at this point, carries total
soluble phosphate concentrations averaging 0.52 mg/1 and ranging as
high as 1.1 mg/1. Total inorganic nitrogen in Grand River water
-------
| | 0-300/ml.
300-500/ml
over 500/ml.
MICH.
IND.
Michigan
iCity
GREAT LAKES - ILLINOIS
RIVER BASINS PROJECT
PHYTOPLANKTON
POPULATIONS
NUMBER PER MILLILITER
SUMMER 1962
U.S. DEPARTMENT OF THE INTERIOR
FED. WATER POLLUTION CONTROL ADMIN.
Great Lakes Region Chicago, III.
GPO B06—408—4
-------
averaged 1.4 mg (N)/l and ranged as high as 3-9 mg/1. Phytoplankton
populations in adjacent Lake Michigan waters were correspondingly
high. Phytoplankton counts averaged 2,230 organisms per milliliter
in summer, 1962 (Figure 3)« A high concentration of 630 phytoplank-
ton organisms was again found in, the Grand Haven area in fall, 1962
(Figure k).
The Manistique River at the northern tip of Lake Michigan,
carried heavy concentrations of algal-stimu3ating nutrients. Soluble
phosphate concentrations in this river averaged O.OU mg/1 and ranged
as high as 0.09 mg/1. Total inorganic nitrogen concentrations averaged
0.^7 mg/1 and ranged as high as 2.46 mg/1. Ehytoplankton populations
in Lake Michigan offshore from Manistique consisted of 528 organisms
per milliliter in spring, 1962. Mid-lake waters in northern Lake
Michigan contained less than 300 organisms per milliliter (Figure 3)-
-------
APPENDIX
30
-------
METHODS
BOTTOM ANIMAJiS
Sampling of bottom organisms was accomplished with three
Petersen dredge hauls at each lake station. These were washed
through U. S. Standard No. 30 mesh bronze seine cloth and the
remaining organisms and debris preserved with formalin for
further analysis in the laboratory.
PHYTOPLAMKTON
Samples for phytoplankton identification were collected
with polyvinylchloride (PVC) sampling bottles attached to a
cable at intervals of zero, 5, 15, 30, 50, 75 and 100 meters
from the surface, and at surface, mid-depth and near bottom
where depths were less than ten meters. Sufficient formalin
was added to each phytoplankton sample to effect a 3 percent
solution. One milliliter of the water sample was placed in a
Sedgwick-Rafter counting cell and examined microscopically at
200 X.
31
-------
LIGHT PENETRATION
Light penetration was determined with a standard, 20
centimeter diameter Secchi disc. The limit of visibility
was defined as the mid-point between the depths of disappearance
upon lowering and reappearance with the disc was again raised.
Measurements were reported in meters.
-------
TABLE 1
DISTRIBUTION OF BOTTOM ORGANISMS BY DEPTHS
LAKE MICHIGAN, 1962-64
Depth in Meters
0-9
10-19
20-29
30-39
k$-k9
50-59
60-69
70-79
80-89
90-99
100-109
110-119
120-129
130-139
140-149
150-159
160-169
170-179
220-229
230-239
260-269
Number per Square Meter
7494
3357
4694
5752
3020
2713
2146
1505
889
642
647
721
26k
425
506
186
201
70
140
88
5019
33
-------
TABLE 2
LAKE MICHIGAN EHYTOPLANKTON
MOST COMMONLY ENCOUNTERED GENERA.
Anabaena Melosira
Anacystis Navicula
Ankistrodesmus Nitzschia
Asterionella Oocystis
Chlorella Phonnidium
Chodatella Rhizosolenia
Closteriopsis Scenedesnius
Cocconeis Schroederia
Cyclotella Selenastrum
Dinobryon Stephanodiscus
Euglena Synedra
Fragilaria Tabellaria
Golenkenia Unidentified Green Coccoids
Gomphosphaeria Unidentified Green
Gonium Flagellates
NOTE: Only those genera whose average total per milliliter
exceeds 10 percent of the average grand total are
considered predominant.
-------
page 1 of 5 pages
TABLE
BIOLOGICAL DATA - LAKE MICHIGAN, 1962-1964
Quad,
1
BOTTOM ORGANISMS
Numbers per square meter
Scuds
Sludge-
worms
Midges
Total*
Spring
1962
PHYTOPLANKTON
Numbers per milliliter
Summer
1962
Fall
1962
Spring 1 summer
1963 1 1963
F-19
E-49
D-19
C-19
G-18
F-18
E-18
D-18
C-18
H-17
G-17
F-17
E-17
D-17
C-17
B-17
H-16
G-16
F-16
1,450
1*70
50
80
1,190
720
2,710
610
180
3,180
1,940
310
1,120
3,840
1,610
1,240
4,020
1,170
220
780
1,310
1,950
4,630
1,670
4,750
1,730
24o
490
l,66o
4,620
100
470
2,180
1,850
400
1,040
1,760
170
100
20
20
20
100
130
140
20
70
140
120
0
X
30
50
260
30
10
0
2,650
2,000
2,210
6,000
3,160
6,200
5,160
920
1,670
5,540
7,030
410
l,6oo
6,090
3,910
1,910
5,490
3,400
4lO
176
171
301
1,036
248
748
1,298 258
233
3,108 224
322
66
420 66
225
357
900 98
246 1,155
398 1,3H
1,588
694
175 1,870
172
350 2,143
588 1,347
1,022
261
66
119
239
546 357
853
148
154
1,106
1,035
1,036
*Includes miscellaneous organisms not mentioned in Table
1. See Figure 6 for locations of quadrangles.
35
-------
page 2 of 5 pages
Quad.
BOTTOM ORGANISMS
Numbers per square meter
Scuds
Sludge- 1 Midges
worms 1 1
! Total*
FHYTOPLANKTON
Numbers per milliliter
Spring]
1962 |
Summer 1 Fall 1 Spring
1962 | 1962 | 1963
Summer
1963
E-16
D-16
C-16
B-16
1-15
H-15
G-15
E-15
D-15
C-15
B-15
1-14
H-14
G-14
C-14
B-14
H-13
G-13
E-13
D-13
C-13
B-13
H-12
130
190
2,260
3,220
1,700
4,360
340
80
150
I,l6o
1,200
3,060
2,280
390
5,820
10
3,970
810
1,200
1,560
500
4,550
190
40
1,590
5,420
380
1,130
180
60
70
2,400
15,910
300
1,240
10
1,370
13,980
I,l4o
530
520
1,620
15,770
860
X
X
80
180
30
40
10
0
X
120
210
40
0
10
50
820
20
20
20
100
90
290
4,
10,
2,
5,
3,
18,
3,
3,
7,
16,
5,
1,
1,
3,
16,
330
240 253
810
270
300
860 1, 503
540 638
l4o 182
220 364
730
560
660
580
410
340
360
530 2,230
400 474
800 378
330 210
980
165
28
402
384
294
70
198
694
896
270
423
134
121
385
242
484
5,860
132
143
1,035
371
154
203
no
2,229
1,867
443
108
145
1,530
295
196
121
1,770
270
572
638
416
2,552
836
660
6,310
^Includes miscellaneous organisms not mentioned in Table.
36
GPO 8O6—40&-3
-------
page 3 of 5 pages
Quad.
BOTTOM ORGANISMS
Numbers per square meter
Scuds
Sludge- 1 Midges
worms 1
Total*
FHYTOPLANKTON
Numbers per millillter
Spring
1962
1 Summer
1962
Fall
1962
Spring
1963
1 Summer
1963
B-12
H-ll
G-ll
F-ll
E-ll
D-ll
C-ll
B-ll
H-10
G-10
F-10
C-10
H-9
G-9
E-9
D-9
C-9
H-8
G-8
E-8
1,810
4,180
3,770
300
1,070
170
5,010
5,150
1,150
i,44o
60
3,770
310
1,760
i4o
1,740
3,020
80
30
30
610
80
980
90
760
60
1,470
320
i4o
70
10
690
120
1,130
90
750
2,890
20
90
10
30
140
80
10
0
X
50
4o
170
60
0
20
60
110
10
4o
80
80
10
0
2,660
4,880
5,180 1,664 354
4oo 252
1,850 121
230 264 154
7,l4o 896 322
6,590
1,630
1,720
90
4,580
520
3,090 616
240 168 308
2,590 319
6,140 3,696 220
230 373
130 189
40 770
1,107
924
1,^52
1,474
1,267
1,232
1,689
512
1,035
5,940
1,078
^Includes miscellaneous organisms not mentioned in Table.
37
-------
Page 4 of 5 pages
Quad.
BOTTOM ORGANISMS
Numbers per square meter
Scuds
Sludge -
worms
Midges
Total
PHYTOPLANKTON
Numbers per milliliter
Spring
1962
Summer
1962
Fall 1 Spring 1 Summer
1962 1 1963 1 1963
D-8
C-8
1-7
H-7
G-7
D-7
C-7
B-7
A-7
L-6
K-6
1-6
E-6
D-6
C-6
B-6
L-5
K-5
G-5
F-5
D-5
C-5
2,990
X
400
630
1,120
20
0
10
0
60
110
950
240
950
0
10
44o
470
20
2,060
20
200
650
0
100
120
540
140
80
1,620
300
10
20
1,240
110
920
90
190
60
no
30
10
130
720
10
0
390
30
160
30
210
280
0
0
40
20
X
80
110
780
10
20
0
10
10
170
3,840
X
920
790
1,900
210
290
1,980
300
70
190
2,250
370
1,960
240
1,020
520
620
60
2,280
200
1,220
463
165
1,254
209
858
308
468
1,067
484
440
1,067
*Includes miscellaneous organisms not mentioned in Table.
38
462
352
2,728
16,209
60,088
2,882
2,100
5,375
6,160 2,018
-------
Page 5 of 5 pages
Quad.
BOTTOM ORGANISMS
Numbers per square meter
Scuds
Sludge- 1 Midges
worms §
Total
Spring
1962
PHYTOPLANKTON
Numbers per milliliter
Summer 1 Fall
1962 J 1962
Spring 1 Summer
1963 ] 1963
N-4
M-4
L-4
K-4
J-4
F-4
L-3
1-3
H-3
E-3
N-2
M-2
K-2
1-2
10
140
T60
1,420
500
44o
1,060
690
10
370
20
20
30
600
10
60
470
180
320
100
730
480
50
380
70
310
100
210
0
30
210
20
30
10
10
30
10
50
180
4o
60
70
20
260
1,510
1,660
860
610
1,810
1,240
80
1,150
290
410
420
890
407
660
319
693
253
231
792
968
308
330
528
1,056
396
896
3,124
968
1,008
*Includes miscellaneous organisms not mentioned in Table.
39
-------
TAELE
MIDGE LARVAE DATA WITHIN TEN MILE LIMIT FROM SHORE
TotaJ
Area Per 1
Percent of
LpNo. Pollution
« Tolerant
Lower Green Bay 201 80
Kenaunee-Sheboygan 53 0
Fort Washington-Kenosha 118 56
Waukegan-Evanston 113 2^
Chicago -Gary 39 6
Michigan City to Buffalo 92 37
Total
Cosmo-
politan
16
29
19
57
79
59
Benton Harbor -South Haven 121 51 34
Saugatuck-Muskegon 6l 74
Ludington-Manistee 124 46
Arcadia -Mackinaw City
Kewaunee-St. Ignace
6l 21
12 0
7
16
56
23
Clean
Water
0
22
3
0
0
0
0
7
10
13
37
Other
4
49
22
19
14
4
5
12
28
10
4o
4o
-------
BCDEFGH IJK.LMNO
NORTH
MILE
FIGURE 6
GREAT LAKES-ILLINOIS
RIVER BASINS PROJECT
LOCATIONS OF QUADRANGLES
IN
LAKE MICHIGAN
U.S. DEPARTMENT OF THE INTERIOR
FED. WATER POLLUTION CONTROL ADMIN.
Great Lakes Region
Chicago. (II.
GPO 806-408-2
------- |