Pushing the limits on nitrate removal: a watershed-scale bioreactor

Faribault Co. SWCD/Michelle Stindtman

Minnesota has an interim goal of 20% reduction in nitrate-N load in Minnesota waters by 2025. One structural drainage practice that can immediately contribute to nitrate reduction is the woodchip bioreactor. Bioreactors are commonly placed at the edge of tile-drained fields 10 to 80 acres in size. A unique three-cell bioreactor in Faribault County was installed in 2016 on a county ditch system, a 632-acre watershed, which is row cropped in corn and soybeans, and a scale that has never been tried. Water quality has been continually monitored by the USDA-Agricultural Research Service (ARS) and Minnesota Department of Agriculture (MDA).
The goal of the proposed work is to further engage the landowners and renters within the watershed in the process of improving water quality. Among these is a landowner who is one of the first to be recognized by MDA’s Minnesota Agricultural Water Quality Certification Program. Our education and outreach will include both informal and formal ways to share information about water quality, bioreactor performance, and weather, and to enlist their perspectives and suggestions on ongoing management of the landscape.
The financial investment requested herein will be used for three purposes: to provide support for continued operation of the bioreactor site; to make flow, nitrate concentration, turbidity, and weather data available in real time to those involved in the project; and to organize and conduct meetings and public outreach.