Runoff Risk: A Decision Support Tool for Nutrient Application Timing

Runoff from working agricultural fields is an inevitable component of the hydrologic cycle. What does not have to be inevitable is runoff transporting freshly applied nutrients.  Conservation practices regarding where and how to apply nutrients are plentiful, yet little formal guidance is provided to farmers on when they should avoid applications due to expected rainfall or snowmelt runoff.  The National Weather Service North Central River Forecast Center (NCRFC) has partnered with several state and federal agencies as well as universities to develop the first real-time runoff risk decision support tool. Utilizing the NWS’s unique capabilities of real-time atmospheric and hydrological modeling on a national scale, these partnerships shape state specific tools providing web-based forecast guidance so that farmers can plan to avoid applying before significant runoff in the next 10 days.  First implemented in 2011 in Wisconsin, increasing interest has prompted enhancing and expanding the tool. A new gridded model will be developed for Michigan, Ohio, Minnesota, and Wisconsin. Incorporating this tool into nutrient management planning could lead to fewer applications before runoff events. Over time this could lead to decreased nutrient yields into adjacent waterbodies.