The
Kalamazoo River Watershed drains 2020 square miles of land
in Allegan, Van Buren, Kalamazoo, Calhoun, Barry, Eaton, Hillsdale
and Jackson counties. Over the years the Kalamazoo River and
many of the streams, lakes and wetlands flowing to it have
had water quality problems. Because of a variety of pollution
reduction programs, policies and efforts some of these water
quality problems have been eliminated or greatly reduced.
However, our work isn't done yet.
One
of the water quality problems in the Kalamazoo River Watershed
is the nutrient enrichment of Lake Allegan. Symptoms are:
algal blooms, low oxygen levels, poor water clarity, and a
fish community so heavily dominated by carp that it is not
considered a diverse or balanced fisheries. Lake Allegan is
an impoundment of the Kalamazoo River, created by the installation
of the Caulkins Dam for generation of hydroelectric power.
Therefore, most of the water and pollutants flowing through
the River and its tributaries eventually reach Lake Allegan.
Although
a variety of factors like flow, nitrogen, and temperature
can affect the symptoms noted above, scientists know that
phosphorus is usually the primary cause of eutrophication,
or nutrient enrichment, in lakes. For this reason, beginning
in 1997, the Michigan Department of Environmental Quality
undertook a study focussed mostly on phosphorus (although
other factors are included) in the Kalamazoo River Watershed
upstream of and in Lake Allegan. 1998 seasonal (May through
October) loadings from most tributaries and from many regulated
industries and waste water treatment facilities were estimated
from data collected 2 or 3 times per month at 29 tributary
mouths, and from 27 point source effluents. Three automatic
samplers provided flow and phosphorus data for storm water
runoff events (many pollutants are washed into rivers, streams,
lakes and wetlands when it rains) in the Kalamazoo River at
Comstock, and at the mouths of the Gun River and Portage Creek.
Water quality monitoring was also conducted at several different
lake depths at 5 stations in Lake Allegan, as well as at the
inlet and outlet.
All
samples from the River and the Lake were analyzed for total
phosphorus, ortho-phosphorus, nitrates, nitrites, ammonia,
suspended solids and total dissolved solids. Average daily
flows have been provided by the U.S. Geological Survey.
Industrial
and municipal point source discharges that monitor phosphorus
in their discharges, account for about 51,661 pounds during
this six month period, or 35% of the total load. The remaining
65% comes from storm water runoff from roads, parking lots,
lawns, farms, industry, and commercial activities; from regulated
discharges that do not monitor for phosphorus; from stream
bank erosion; from poorly functioning septic systems; from
livestock, pets and wildlife; and from illicit discharges.
|
|
Kalamazoo
River |
Immediate
Drainage |
Allegan
WWTP |
Precipitation |
Monthly
Total |
|
April |
37,153 |
522 |
130 |
42 |
37,947 |
|
May |
32,691 |
216 |
173 |
42 |
33,122 |
|
June |
24,723 |
210 |
146 |
41 |
25,121 |
|
July |
21,055 |
216 |
160 |
42 |
21,473 |
|
Aug. |
17,343 |
206 |
206 |
42 |
17,797 |
|
Sep. |
12,191 |
158 |
136 |
41 |
12,527 |
|
Total |
145,156 |
1528 |
951 |
250 |
147,885 |
|
% |
98.2 |
1.0 |
0.6 |
0.2 |
100 |
|
1998
Lake Allegan total phosphorus loads, lbs. |
Because
other factors may also be playing a role, there is now consideration
of studies to examine:
- phosphorus
flux from sediments, and
- how
significantly Lake Allegan algal communities are limited
by phosphorus (vs. nitrogen).
A
comparison study of Morrow Pond, another shallow impoundment
of the Kalamazoo River, is underway this summer. This study
should provide some information on the links between ph
osphorus
and other variables like fish communities and clarity.
Since
phosphorus is only one variable (albeit acritical one) affecting
lake ecology, proposed water quality goals for Lake Allegan
also include water clarity, chlorophyll a (a measure of the
amount of algae in the water), fish community composition,
dissolved oxygen levels, and the absence of significant blue-green
algae blooms.
Total
Maximum Daily Load (TMDL) processes are mandated by the federal
Clean Water Act for all water bodies with water quality impairments.
In Michigan, the Department of Environmental Quality (MDEQ)
is charged with ensuring that TMDLs are developed.
In
the Kalamazoo River/ Lake Allegan TMDL process, MDEQ has been
joined by a number of watershed partners to develop the TMDL.
This committee consists of representatives and individuals
from regulated point sources, environmental groups, local
government, agriculture, extension, and others. This group
is by no means entirely representative of all watershed perspectives.
This is an open process, and anyone is welcome to participate.
Since reductions will quite possibly affect you, make sure
your knowledge and experience are part of the planning process.
The next step is for technical experts to synthesize these
data and provide estimates of the "capacity" of Lake Allegan
to utilize phosphorus, and maintain a healthy, balanced system.
Based
on these estimates, the Kalamazoo River/Lake Allegan TMDL
committee must:
- set
water quality goals
-
decide from which sources reductions must come
-
develop a reduction strategy
- determine
what monitoring and additional study is necessary to refine
plans, document reductions, and track the responses of the
Lake Allegan ecosystem
The
TMDL Committee is on the fast-track to have a draft report
by Fall 1999. Most of the issues listed above, must be addressed
in this draft. The TMDL report is due to U.S. EPA by early
2000 for their review and comment. However, planning and implementing
reductions is a long-term proposition. The TMDL process is
an iterative one where we will be regularly revisiting our
numbers, our goals, our progress, our partners, and most importantly
the Kalamazoo River and Lake Allegan.
Click
here to download a printable brochure version of the overview
presented above.
If
you would like more information please contact:
MDEQ,
Kalamazoo District Office (269) 692-6970