July-August 2002

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Raccoon River Watershed Project

Faced with a nonpoint-source problem, diverse groups came together to find solutions: farmers, businesses, academia, private foundations, and local government agencies.

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By Eric Woolson

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Rural concerns about possible federal regulations stemming from USEPA's total maximum daily load (TMDL) program and urban concerns about excessive levels of nitrate in drinking-water supplies have spawned a succession of unusual alliances to identify and reduce nonpoint pollution in the rolling farmland of west-central Iowa.

Enduring partnerships that are the legacy of the Raccoon River Watershed Project (RRWP) can provide a role model for future efforts in similar watersheds.

Recent History

The Raccoon River and its tributaries flow across west-central Iowa, draining all or part of 17 of Iowa's 99 counties before emptying into the Des Moines River in Des Moines. More than 370,000 people–13% of Iowa's population–rely on sources within the watershed for drinking water.

But sections of the Raccoon River, identified in Iowa's Federal Clean Water Act 303(d) list of impaired waters, pose difficult challenges for surface-water professionals. The Raccoon River and North Raccoon River were cited as low priorities for fecal coliform bacteria, and the Raccoon River was cited as a high priority because of nitrates.

The watershed's high concentrations of nitrates have exceeded the federal maximum contaminant level (MCL) standard of 10 mg/l with enough frequency since the late 1980s to warrant the Des Moines Water Works's (DMWW) installation and operation of the world's largest nitrate removal facility. Smaller facilities, operating in Florida and California, might produce 1 million to 2 million gal. of processed water per day. The DMWW is capable of producing 10 million gal. of water per day.

"We saw the trends, and at that point in time we decided we needed to do the necessary experimentation to determine how to best address the problem," says L.D. McMullen, general manager and chief executive officer of the DMWW.

Nitrate, a plant nutrient and inorganic fertilizer, is especially dangerous to infants under six months of age because it reduces the blood's ability to carry oxygen. This condition, known as methemoglobinemia or "Blue Baby Syndrome," is a life-threatening condition requiring immediate medical attention. Research also indicates a strong correlation between nitrates and certain types of cancer in adults.

"There is enough evidence and concern in the research community that we need to be conservative in our approach to protecting the public from nitrates in drinking water," McMullen says.

The nitrate removal facility, completed in 1992, is activated when the detected levels reach 9 parts per million (ppm). The facility uses a process called ion exchange. A resin material that has sodium and chloride ions on it is in each of eight nitrate-removal facility vessels. As the nitrate-laden water passes through the resin material, the nitrate ions are captured, and a chloride ion is released into the water. The nitrate-reduced water is then blended with treated water to produce safe, clean drinking water with nitrate concentrations below the 10-mg/l MCL. This ion exchange process is similar to that of a home water-softening device that removes calcium and magnesium ions from the water, exchanging them for sodium ions.

Coping with high nitrate concentrations has been "a real challenge, especially in the springtime," McMullen notes. "We make decisions on whether to take water from the Raccoon River or the Des Moines River based on nitrate values on a particular day."

Originally intended to operate approximately 35-40 days a year, McMullen says the facility was needed 109 days in 2000, at a daily cost of $3,000. For the DMWW, the most cost-effective option would be to prevent nitrates from getting into the source water by implementing locally driven source-water protection plans throughout the watersheds. "We constructed the nitrate removal facility, but we weren't going to accept it as the solution to the problem," explains McMullen. "We were looking for ways to reverse the trend."

One reason for the watershed's high nitrate concentrations is that 1.7 million of its 2.3 million ac. are in production agriculture: corn, soybeans, livestock, and poultry. "Anywhere from 850,000 to 900,000 acres of corn are grown in the river basin. The average rate of fertilizer application is anywhere from 120 to 140 pounds per acre," explains Roger Wolf, who directed the RRWP and now serves as executive director of a successor organization, Agriculture's Clean Water Alliance (ACWA).

McMullen also notes that the watershed is part of the Des Moines lobe of the Wisconsin Glacier. The result is a swampy, prairie pothole region that farmers must tile and drain if the terrain is to be converted into productive cropland.

"Surface-water professionals know better than anyone that the tiles really end up being a short circuit of the natural process to remove nitrates from water. The tiles are direct pipelines into the river. So the combination of geology and a heavily agricultural use of the land makes the watershed a very big contributor of nitrate into the Mississippi River and Gulf of Mexico," says McMullen.

The Des Moines River watershed, which receives the Raccoon River's flow, has a similar natural composition but has not been subject to the same level of extensive tiling. However, McMullen observes, the nearby Cedar River and Iowa River watersheds that feed into the Mississippi River along Iowa's eastern border also are trending the way of the Raccoon as farmers tile more acres.

"The Stars Lined Up"

In the early 1990s, a number of forces were converging that could eventually benefit the Raccoon River watershed. The state associations of corn and soybean growers and cattle, pork, and poultry producers teamed with the Iowa Agribusiness Association and Iowa Farm Bureau to form the Iowa Nutrient Management Task Force. That task force produced a number of recommendations to improve Iowa's water quality, and the RRWP emerged as an education and demonstration vehicle.

"The stars lined up right," says Wolf. "You have 300,000-plus people in Des Moines who get their water from the Des Moines Water Works. The state's largest newspaper is here raising awareness of the challenges that the water works faces. There was the recognition by farm interests that fertilizer, manure management, and the act of agriculture contribute to water-quality difficulties. Frankly, the potential threat of regulation was playing into it. There was also a lot of recognition that we could improve the on-farm efficiencies of agriculture and achieve environmental protection at the same time if we could show farmers how they could view these types of things. It wasn't what I call a true comprehensive watershed management approach, but we knew it could make a real difference."

Unlike many other watershed-focused initiatives, according to Wolf, the RRWP set out to create a climate of private/public collaboration and action designed to enhance the leadership capabilities of all involved parties. The effort really began to gel with a commitment from the Northwest Area Foundation and involvement from the DMWW and Iowa Natural Heritage Foundation.

The Northwest Area Foundation recognized the uniqueness of the RRWP partnership and supported its vision. From 1994 to 2000, the foundation contributed $830,500, which enabled RRWP partners to attract at least another $750,000 in public and private funds. These funds were highly leveraged and served as a catalyst for not only cash, but also many in-kind contributions. The foundation's support was an investment into the social and human capital needed to create more sustainable communities for the future.

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The foundation, established in 1934, funds projects in Iowa and seven other states once served by James J. Hill's Great Northern Railway. Created by Hill's son Louis, the foundation invests millions of dollars each year to provide access to knowledge, financial resources, products, and services to help communities overcome barriers that might be hindering their creation of a healthy, sustainable future.

The RRWP sought to increase the adoption of agricultural technologies or best management practices through demonstration projects and publicity. Active grassroots efforts were instrumental to the project. Next Page >

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