IGS has worked with partners including The Nature Conservancy, Iowa Soybean Association, U.S. Fish and Wildlife Service, and Linn County Conservation Board to monitor oxbow restorations in central and eastern Iowa.
At the central Iowa site, IGS monitored an oxbow that was reconstructed to receive flow and nutrients from subsurface field tiles. At the eastern Iowa site, IGS reconstructed the oxbow to receive inputs from groundwater seepage and overbank flooding.
IGS research has shown that oxbows fed by tile drainage provide greater nitrate mass reduction than oxbows fed by flood pulses and groundwater. Data from these oxbow studies are being used to develop a new INRC conservation practice centered on oxbows. Study results were published in Ecological Engineering and Journal of Environmental Management.