Water Resources Research Act Program

Details for Project ID 2012MN314B

Tracing nutrient sources at the land-water interface in urban environments

Institute: Minnesota
Year Established: 2012 Start Date: 2012-02-01 End Date: 2014-02-28
Total Federal Funds: $59,484 Total Non-Federal Funds: $113,474

Principal Investigators: Jacques Finlay, Sarah Hobbie

Abstract: Water quality in urban freshwaters is widely impaired, with little recent improvement and much potential for further degradation due to future urban intensification. Eutrophication from excess nitrogen (N) and phosphorus (P) inputs is a leading cause of water quality decline that impacts local uses of high value urban aquatic ecosystems and contributes to downstream water quality problems. Implementation of best management practices (BMP’s) to reduce runoff and treat urban storm water can help improve urban water quality, but there is limited understanding of the specific sources of nutrients to urban waters, limiting the ability to manage urban ecosystems for future conditions and to make changes that could lead to systemic improvements in conditions of urban streams and lakes. The proposed project leverages support from a University of Minnesota Institute on the Environment seed grant and ongoing collaboration with a local watershed district in seeking to develop and apply tracers for specific nutrient sources to urban streams and lakes transported though storm drains and groundwater. The proposed work will evaluate tracers of N and P directly, via isotopic analyses, and indirectly, through analyses of tracers of flow paths and interactions in small urban watersheds in St. Paul, Minnesota. Tracers will be assessed through analyses of primary sources of urban nutrients (e.g., soils and sediment, fertilizer, pet waste, vegetation, precipitation) on the landscape, in streets and catch basins, and in storm drains. Source tracer information will be used to identify N and P sources both within and across storm events and for baseflow conditions across an annual cycle. The public and local governing agencies are committed to greater involvement in water quality improvement. Greater understanding of nutrient sources in urban areas will allow more effective guidance of volunteer activities and more efficient and successful management of urban watersheds.