Runoff Risk Guidance Tool to Mitigate the Water Quality Impacts of Nutrient Application

Lynker assisted the NOAA National Weather Service (NWS) North Central River Forecast Center (NCRFC) develop an enhanced Runoff Risk Guidance capability using the NWS Distributed Hydrologic Model. This project developed and implemented a multi-agency collaborative Runoff Risk Advisory Forecast (RRAF) tool for manure producers and nutrient applicators in multiple states that provides a dynamic, real-time model-based decision support tool for farmers and land managers to help with short-term application decisions.

Farmers often apply manure and nutrients to fields at times dictated as much by factors such as farming schedules and manure storage capacity than simply by when the plants need them. This often leads to poorly timed applications. Application prior to a rainfall-runoff event might mobilize nutrients to the hillslope and channel and away from where they are needed, resulting in detrimental impacts on water quality such as algal blooms and hypoxia, and at spatial scales from the contamination of local drinking wells to fish kills in the Great Lakes and Gulf of Mexico. Getting the timing right for application of nutrients is key in this regard. Specifically, it is critical to not apply nutrients before heavy rain or anticipated snowmelt which could carry nutrients right off the fields and into nearby water bodies.

Lynker helped develop and then enhance the RRAF by integrating, testing and validating the higher resolution distributed hydrologic model, thus enabling assessments of risk to be conducted at a finer spatial scale. Lynker also worked on RRAF stakeholder outreach and training. The project has helped NWS meet its Weather-Ready Nation mission of improving and expanding decision support services to a wide array of decision-makers and leveraging its capabilities into new areas such as water quality across the entire hydrologic spectrum ranging from local streams to oceans.