Area beach closings up, officials
By Karen Berkowitz
Pioneer Press Online
Swimming bans related to high bacteria levels were once
a rarity at North Shore beaches. They often occurred when
heavy rainstorms forced a release of untreated sewage
into Lake Michigan.
But the frequency of such bans has stepped up this season
as Evanston, Wilmette, Winnetka and Glencoe have adopted
uniform E. coli testing procedures at the urging of the
Illinois Department of Public Health.
Last year, Evanston beaches were closed only once for
high bacteria levels - and, then, as an automatic response
to the opening of the North Shore Channel locks during
heavy rains to relieve pressure on sewers and minimize
So far this summer, there have been four days on which
some or all of Evanston's five beaches were closed to
swimmers due to high E. coli counts that showed up on
water samples taken the previous day. On two recent days
in July, the bans also extended to the city's dog beach.
The experience in Winnetka has been similar, officials
"There have been eight days on which at least one
of our beaches was closed because of bacteria and two
days on which all of the beaches were closed," said
Liza McElroy, Winnetka director of parks and recreation.
Winnetka has five beaches, three of which are ordinarily
open to swimmers.
"We are probably on a par with last year" in
the number of closings, McElroy said, "but clearly
within the last two to three years we have had more closings
than previous to that. We still have another month of
"I'm not in a panic mode about this, but it is a
very curious situation," McElroy said.
"Why on some days are two beaches closed and three
open, or one closed and four open? Who knows?" said
McElroy, who is mystified by the variances, as are other
park operators on the North Shore.
Previously, Evanston, Wilmette, Winnetka and Glencoe
conducted independent water quality tests and used locally
set standards for determining when to close the beaches
With the exception of Glencoe last year, the suburbs
used a test that counted fecal coliform bacteria, a broad
group of organisms that includes some that are benign
- and even beneficial - to humans.
This year, the Illinois Department of Public Health provided
some grant funding to allow the suburbs to uniformly switch
to a test for E. coli that the U. S. Environmental Protection
Agency views as the most meaningful indicator of the kind
of bacteria that sickens people.
"There is no historical data for E. coli at these
North Shore beaches. We are starting to begin that database
right now," said Lane Drager, environmental engineer
with the Illinois Department of Public Health.
While there is no direct correlation between the old
fecal coliform test and the new E. coli test, the switch
effectively lowered the standard for beach closings, according
On the recommendation of the EPA, park officials are
banning swimming when E. coli colony counts measure 235
per 100 milliliters of lake water, about one-fifth of
Previously, the standard for closing a beach was 500
colonies of bacteria per 100 milliliters of water. Drager
said roughly 400 of the 500 bacteria counts would have
been E. coli, so the new test effectively lowered the
standard from 400 to 235.
"There are a few more closures (on the North Shore)
this year. It was expected, based on more stringent standards,"
Drager said. "In comparison to Chicago and Lake County,
the North Shore beaches have had less closures."
Drager said the wet weather with high-intensity rainstorms
also could be contributing to the high bacteria levels
at some North Shore beaches.
"There are a lot of ravines where the water runs
directly to their public beaches," he said. Likely
sources of fecal matter at North Shore beaches include
water running off parking lots or through ravines with
pet and animal waste; older, leaking sewers; improperly
combined sewer systems and seagulls.
The Wilmette beach at Gillson Park has been closed twice
so far in 2003 due to high bacteria levels, once on June
20 and again on July 22, according to lakefront manager
Currently, water samples must incubate for 24 hours before
the concentration of E. coli is known, meaning the beaches
may be open to swimmers when bacteria levels are high
and closed after the bacteria counts have subsided.
Winnetka recently purchased its own E. coli testing system
with grant money and will begin conducting its own tests
Unfortunately, said McElroy, "We didn't purchase
the equipment that could have the test results back sooner,
because," she added, "there isn't any."