Iowa Sierrans, Eric, Kendra, et al:
FYI. Thought you'd be interested.
Lyle
6/25/03 Des Moines Register Editorial: Get serious: Clean up the lakes
"Swimming not recommended" signs don't do much for Iowa's reputation.
By Register Editorial Board
06/24/2003
------------------------------------------------------------------------
More bad news from Iowa's weekly beach-monitoring reports. As of Friday,
three of 33 state lakes had advisories posted that swimming is not
recommended because of unacceptable levels of E. coli: Lake Geode in Henry
County, Rock Creek Lake in Jasper County and Backbone Lake in Delaware
County. This is not a selling point for the state, which is trying to
pinpoint pollution sources and clean them up.
For an advisory to be posted, a lake must either (1) exceed a one-sample
reading of 235 colonies of the bacteria per 100 milliliters of water, or (2)
exceed a geometric mean of 126 colonies per 100 milliliters based on five
samples taken over 30 days. The state is following federal Environmental
Protection Agency recommendations.
E. coli is a subset of fecal coliform bacteria, which is found in the
intestinal tract of warm-blooded animals. Its presence indicates fecal
matter is in the water and that the potential exists for people to become
sick. The elderly, young children and anyone with immune disorders are most
at risk.
The Iowa Department of Natural Resources is trying to get a handle on the
pollution by studying sites with consistently high bacteria levels.
Backbone, for example, was closed for nearly two months until recently while
the state looked into whether a nearby sewage-treatment plant was a source.
It was ruled out. The DNR is also studying Geode, among other lakes.
In general, blame for E. coli in the water may belong to various sources,
including manure dirtying streams that feed lakes, wildlife droppings and
human sewage. The state is sampling watershed tributaries and hopes in the
future to be able to use DNA testing to piece together the puzzle, which
will vary from place to place.
Rain can kick up levels of E. coli in a lake, and a few days of sunshine can
bring them back down. The state tests lakes on Mondays and Tuesdays, but it
takes until Friday until an accurate reading is available. So a lake not
considered safe for swimming based on samples taken Monday or Tuesday could
be just fine by Wednesday or Thursday. The inability to get real-time daily
readings is a frustration. The state ends up posting warnings when they may
be out of date or not posting them when warranted.
The science may improve. Far more important is improving the water quality.
With about half a dozen lakes where"swimming not recommended" signs have
been posted at various times this season, Iowa needs to put more effort into
finding the sources of contamination and mitigating them.
Iowa should be able to brag about its beautiful, clean lakes - and it can't.
*************************
Lyle R. Krewson
Sierra Club Conservation Organizer
6403 Aurora Avenue #3
Des Moines, IA 50322-2862
515/276-8947
515/238-7113 - cel
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Lyle R. Krewson
6403 Aurora Avenue #3
Des Moines, IA 50322-2862
515/276-8947
515/238-7113 - cel
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