Combining Conservation and Agriculture
From constructed wetlands to cover crops, Conservancy staff at the Franklin Demonstration Farm are finding innovative ways to clean our water.
– Dr. Maria Lemke, Aquatic Ecologist for The Nature Conservancy in Illinois
After more than 20 years of research, Rick Twait finally sees the work paying off. He and scientists from The Nature Conservancy and University of Illinois have determined a method to help provide clean drinking water to 70,000 people in Bloomington, IL.
“This is a very exciting, very gratifying time,” said Rick, the superintendent of water purification for the City of Bloomington. “We’ve finally found a potentially reliable and consistent way to remove nitrates from Lake Bloomington.”
Lake Bloomington, one of two reservoirs that provide the city with its drinking water, has historically exceeded the Environmental Protection Agency’s drinking water standard of 10 mg/L of nitrates. Nitrates in drinking water can lead to “blue baby syndrome,” which causes a baby’s skin to appear blue-gray in color due to a lack of oxygen in the blood.
The Nature Conservancy has collaborated with a suite of partners to design a “constructed wetlands” program along Money Creek and Sixmile Creek, tributaries to the Mackinaw River and sources for Bloomington’s drinking water reservoirs, Lake Bloomington and Lake Evergreen. Partners in this project include: City of Bloomington, Environmental Defense Fund, United States Department of Agriculture, Natural Resources Conservation Service, Soil and Water Conservation District, University of Illinois and Illinois State University.
The lands surrounding Lake Bloomington are 80-90 percent agricultural, farmed for corn and soybeans and drained by surface channels and subsurface tiles. Ten years of the Conservancy’s and its partners’ extensive research has shown that wetlands constructed in targeted agricultural fields effectively remove 46-90 percent of inflowing nitrates from underground tiles that would otherwise enter adjacent streams and rivers.
While plans are still in progress, these organizations are working with farmers along Money Creek and Sixmile Creek to construct wetlands within their fields. Farmers are looking forward to the partnership.
“I think this is an interesting project,” said a McLean County farmer interested in the constructed wetlands program. “If it isn’t going to impact me in any other way than a few acres out of production, then I believe it has a large enough benefit that works for everybody. I’m interested in studying it; it seems like a practical, economical way for us to be good stewards.”
While this work is local to Illinois, it also aligns with the Conservancy’s global Water Funds program, which works with investors−primarily large businesses and government agencies−to establish funds for conserving key lands upstream that naturally filter water and reduce its speed across the land. At the same time, habitat for native plants and wildlife is preserved.
“What is really exciting is that this is a collaboration of an amazing group of partners that bring their experiences, expertise and enthusiasm to this project,” said Dr. Maria Lemke, aquatic ecologist for the Conservancy. “Collectively, this team has the capacity to demonstrate the effectiveness and efficiency of constructed wetlands and develop an innovative partnership model that leverages Farm Bill programs.”
This new project leverages Farm Bill programs through encouraging the adoption of constructed wetlands across agricultural watersheds, improving local drinking water quality and, on a larger scale, helping abate hypoxia in the Gulf of Mexico.