Much of the nitrogen rich sediment that enters the Gulf of Mexico originates from the upper Midwest. Water quality and the management of nutrients that leave farm fields can sometimes be enhanced by the deployment of specific tools. One such tool that Sand County Foundation has studied is the subsurface bioreactor.
Subsurface bioreactors can chemically reduce the discharge of nitrates if properly located and sized. Typically a pit is dug at the outlet of a fields drain tile and discharged water reacts with a carbon source in the pit (typically wood chips). The result is cleaner water.
When utilized in conjunction with nutrient management planning and careful application of just the right amount of nitrogen fertilizer, water quality improvements can be significant. Research conducted with the University of Illinois at Urbana-Champaign found measurable water quality benefits.
For more, view these press clippings:
First-Ever Bioreactor Recharge in Iowa