The regional body of governments is working with RDG Planning & Design to come up with a watershed plan with the help of a $123,000 grant from the Iowa Department of Natural Resources.

The authority formed last year to address the creek’s high nitrate and bacterial levels, cloudiness, flash flooding and stream bank erosion. The planning process will start in February.

“Water knows no political boundaries,” said Tom Hadden, chairman of the Walnut Creek Watershed Management Authority and the city manager of West Des Moines. “This is a great example of local governments working together for the benefit of all metro residents for generations to come.”

The work comes as Des Moines Water Works moves to sue three northwestern Iowa counties under the Clean Water Act, contending that previous voluntary efforts haven’t effectively reduced nitrate levels in the Raccoon and Des Moines rivers that require expensive treatment. Nitrate can cause a condition that suffocates babies and has also been associated with several cancers.

Agriculture groups, Gov. Terry Branstad, and others have maintained that the state’s Nutrient Reduction Strategy, which calls for paying farmers to use conservation techniques on the land, is the best approach to reducing the pollution, which also is tied to a summertime “dead zone” in the Gulf of Mexico.

The Walnut Creek watershed is one of the most quickly urbanizing watersheds in Iowa, encompassing 52,643 acres in Dallas and Polk counties and including portions of Clive, Dallas Center, Des Moines, Grimes, Johnston, Urbandale, Waukee, West Des Moines and Windsor Heights. The watershed is approximately 60 percent urban and 40 percent agricultural.

The effort to protect the Walnut Creek watershed is part a larger regional goal of preventing further deterioration of the natural environment, a goal identified in the Tomorrow Plan blueprint for the Des Moines area’s future. The Des Moines Area Metropolitan Planning Organization is helping to establish the WMA. Read more