Polluted Chicago Water Travels Over 1,000 Miles and Wreaks Havoc in the Gulf

An algae bloom in the Gulf of Mexico has resulted in an oxygen-starved area the size of Massachusetts. Part of the problem is sewage runoff flowing south from Chicago.

1 minute read

June 22, 2019, 7:00 AM PDT

By Camille Fink


Mississippi River Missouri

Dan Brekke / Flickr

Tony Briscoe reports that a giant algae bloom in the Gulf of Mexico is being fed by agricultural and urban runoff from the Midwest flowing into the Mississippi River. "While the agricultural runoff from farms — exempted under the Clean Water Act — is the main driver of the Gulf dead zone, Chicago’s sewage is the largest single source of phosphorus pollution."

Heavy rains are flushing more nitrogen from fertilizer and phosphorous from sewage into the river, and the resulting dead zone in the Gulf of Mexico is killing off fish and shrimp populations. But dead zones are also a problem in the Great Lakes, with large algae blooms in Lake Michigan and Lake Erie, reports Briscoe.

Environmental groups want to see less water pollution coming out of Chicago, and they are also working to curb agricultural runoff. "In collaboration with the agricultural industry, the [Natural Resources Defense Council] pushed to incentivize the use of cover crops, plants like cereal rye that soak up water and nutrients during the off-season," writes Briscoe.

Friday, June 14, 2019 in Chicago Tribune

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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