\!
Ïj‘
Steady increases in the phosphate level were associated with rising con—
centrations of microorganisms overthe past 20 years, as measured in mixed
offshore and shore water at the Chicago South Water Filtration Plant. These
-organisms have caused a number of expensive problems at the plant—as they
have at water treatment plants elsewhere. For example, the lamentous algae
'Cladophom proliferated on the bottom of Lake Michigan under the inuence
of waste nutrients and broke loose late in the summers of 1968—1971, clogging intake screens to the point that they had to be cleaned by hand. Two
other microorgæ1isms present in the winter recently have affected the water
chemistry to the degree that greater doses of coagulants are now needed to
_{, : …
reduce tu’rbidity in* the drinking water supply; a third microorganism imfî?
parted a cod—liver—oil taste and smell to the water, necessitating a counter—
active increase in chlorination» or activated carbon treatment. Algal inter—
ference with water treatment also has occurred at facilities in Green Bay,
Sheboygan, Milwaukee, Waukegan, Evanston, Gary, Michigan City, Benton
{
€Harbor, Holland, Grand Rapids, and MŒkegon.
On the…basis of evidence produced at the Lake Michigan conferences, the
îf‘ ,j Ï,
four surrounding stateshave uhdertaken a.program to improve municipal
waste treatment to.achieve removal of 80 percent of the total phosphorus in
waste treatment plants that border the lake. Industrial wastes will require
_
=
separate treatment if not treated in the municipal plants. The effect of this
action on the lake’s ecology remains to be seen; the program will not produce
’
substantial results immediately, since initial time has to be devoted to nancing, personnel training, and alteration of facilities.
'
The prognosisstl appears serious for Lake Michigan for several reasons.
In the rst «place, removing even 80 percent of the phosphates in man—made
j'_g
wastes leaves quite a lot of food for the algae. The latest estimates of phos—
phorus input into the Lake Michigan Basin made by the Phosphate Technical
Comittee-arez A total of about 16.7 million pounds of phosphorus com—
Ï*Α Îpounds—a conservave esümate—enters the basin each year. Of that total,
_
about 13.8 million pounds come from-municipal treatment plants, other do—
mestic sources,or industrial plants; two million pounds are in runoff from ag—
ricultural lands,urban and rural areas, and land development or construction
areas; 1.4 million poùndsare contributed by miscellaneous sources such as de—
caying leaves and rottîng crop vegetation.
Ïh€Ë ancipated 80 percent reduction of phosphates in mu—
nicipaland industriahdischæ*ges, “encouragement of improved agricultural
_
practices
phosphate
from farm lands. For the moment, assumethat
this gives us a future across—the-board reduction of 80 per—
.
V‘Èry°PmmStœ 1Ïa$Surnption, according to EPA experts. Under the best
of crrcumstances.
us with some 3.3 million pounds of phos—
_
phorus compoundinput
This in1itself is a substantial amount of nu—
lâËâÏïä îÊËïÊC le,‘atiÿëit will
be mag1èd in coming years as both popu—
'
ul ü
,9n}e,-forecasts for the
Lake Michigan Basin predict
‘
“älluse from1ts 1960 level of
4.2 million
to 12.1 million
)
Y
,
an
Industrial
wastes In the same penod will increase by a
'
Assault on a Lake
.
Ïj‘
Steady increases in the phosphate level were associated with rising con—
centrations of microorganisms overthe past 20 years, as measured in mixed
offshore and shore water at the Chicago South Water Filtration Plant. These
-organisms have caused a number of expensive problems at the plant—as they
have at water treatment plants elsewhere. For example, the lamentous algae
'Cladophom proliferated on the bottom of Lake Michigan under the inuence
of waste nutrients and broke loose late in the summers of 1968—1971, clogging intake screens to the point that they had to be cleaned by hand. Two
other microorgæ1isms present in the winter recently have affected the water
chemistry to the degree that greater doses of coagulants are now needed to
_{, : …
reduce tu’rbidity in* the drinking water supply; a third microorganism imfî?
parted a cod—liver—oil taste and smell to the water, necessitating a counter—
active increase in chlorination» or activated carbon treatment. Algal inter—
ference with water treatment also has occurred at facilities in Green Bay,
Sheboygan, Milwaukee, Waukegan, Evanston, Gary, Michigan City, Benton
{
€Harbor, Holland, Grand Rapids, and MŒkegon.
On the…basis of evidence produced at the Lake Michigan conferences, the
îf‘ ,j Ï,
four surrounding stateshave uhdertaken a.program to improve municipal
waste treatment to.achieve removal of 80 percent of the total phosphorus in
waste treatment plants that border the lake. Industrial wastes will require
_
=
separate treatment if not treated in the municipal plants. The effect of this
action on the lake’s ecology remains to be seen; the program will not produce
’
substantial results immediately, since initial time has to be devoted to nancing, personnel training, and alteration of facilities.
'
The prognosisstl appears serious for Lake Michigan for several reasons.
In the rst «place, removing even 80 percent of the phosphates in man—made
j'_g
wastes leaves quite a lot of food for the algae. The latest estimates of phos—
phorus input into the Lake Michigan Basin made by the Phosphate Technical
Comittee-arez A total of about 16.7 million pounds of phosphorus com—
Ï*Α Îpounds—a conservave esümate—enters the basin each year. Of that total,
_
about 13.8 million pounds come from-municipal treatment plants, other do—
mestic sources,or industrial plants; two million pounds are in runoff from ag—
ricultural lands,urban and rural areas, and land development or construction
areas; 1.4 million poùndsare contributed by miscellaneous sources such as de—
caying leaves and rottîng crop vegetation.
Ïh€Ë ancipated 80 percent reduction of phosphates in mu—
nicipaland industriahdischæ*ges, “encouragement of improved agricultural
_
practices
phosphate
from farm lands. For the moment, assumethat
this gives us a future across—the-board reduction of 80 per—
.
V‘Èry°PmmStœ 1Ïa$Surnption, according to EPA experts. Under the best
of crrcumstances.
us with some 3.3 million pounds of phos—
_
phorus compoundinput
This in1itself is a substantial amount of nu—
lâËâÏïä îÊËïÊC le,‘atiÿëit will
be mag1èd in coming years as both popu—
'
ul ü
,9n}e,-forecasts for the
Lake Michigan Basin predict
‘
“älluse from1ts 1960 level of
4.2 million
to 12.1 million
)
Y
,
an
Industrial
wastes In the same penod will increase by a
'
Assault on a Lake
.