Lake Pollution from Entering
Streams
C.   C.   DEWITT   AND  J.   F.   WHITE
Michigan State College
East Lansing, Michigan
This is a preliminary report of a waste disposal study sponsored by
the Gerber Products Company of Fremont, Michigan. The data
reported were obtained from samples taken near the mouth of Darling
Creek which flows into Fremont Lake.
It has been established that when water carrying waste material
enters a flowing stream, the waste material can be detected for a con¬
siderable distance downstream. A different situation exists when waste
material is discharged into large, relatively still bodies of water such as
the Great Lakes or tidal basins. Small, non-stagnant lakes are not
included in these classes of waste receivers. Dams in streams produce
bodies of water resembling many small inland lakes in that they possess
both a flowing inlet and outlet. In many surveys of stream pollution
the samples have been obtained near the dam spillway. Public health
officials express the opinion, however, that the pollution in a small lake
is local in character. The data presented show that pollution is confined
to the area near the lake inlet.
In the present instance both the industrial and sewage wastes are
treated by the Fremont municipal sewage disposal plant. The industrial
waste volume from the cannery represents about two-thirds of the
total volume. At the disposal plant solids are settled and sent to a
digester, the effluent from the settling chamber is treated in a high-rate
biological filter. The final effluent is partially chlorinated; this effluent
enters Darling Creek about one-half mile upstream from its mouth.
The creek enters the lake near the most northeasterly portion; the lake
outlet is diagonally southwest. The water is controlled by a spillway
dam at the outlet. The lake area is approximately 800 acres; its maxi¬
mum measured depth about 90 feet. The lake bottom is marl, with
a small sand beach near the creek mouth. The lake shore adjacent to
the creek mouth has been protected against erosion by rocks and broken
concrete. The entire north lake shore is residential; much of the
remaining shore line is reedy with farm land beyond.
In September, 1944, representatives of the Stream Control Com¬
mission of the State of Michigan made two series of tests on Fremont
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