398086 - DEVELOPMENT OF A GIS-BASED WATER QUALITY MODEL FOR THE CITY OF MINNEAPOLIS
Monday, June 4
4:00 PM - 5:30 PM
Location: Mirage Room
Sarah Stratton, Minneapolis, MN – Barr Engineering Co.; Lois Eberhart, Minneapolis, MN – City of Minneapolis Publcs Work; Nicholas Cantarero, Minneapolis, MN – City of Minneapolis Public Works
Water quality models which predict pollutant loading and their fate and transport have become an essential tool for assessing water quality impairment, establishing permit and loading requirements, and evaluating and designing best management practices (BMPs) for stormwater treatment. Water quality models which calculate pollutant transport on a continuous basis by detailed parameterization of physical and chemical processes often exhibit significant uncertainties which do not justify the detailed model parametrization. In addition, such models can be difficult to develop for areas as large as the city of Minneapolis and associated long model simulation times often make evaluation of water quality development alternatives time and cost prohibitive.
Based on a desire to evaluate the city-wide performance of stormwater BMPs, a GIS-based water quality model was developed for the city of Minneapolis. The BMPs performance was modeled using results of the study done for the development of the Minimal Impact Design Standards (MIDS) calculator. Using a suite of ESRI ArcGIS toolboxes, the GIS-based water quality model (1) predicts annual areal loading of runoff, total suspended solids (TSS) and total phosphorus (TP) from land use datasets, (2) routes and accumulates runoff and pollutants through a defined utility network, and (3) predicts annual removal of pollutants by stormwater BMPs. The model allows the user to spatially place BMPs within a utility network, automatically regenerate subwatershed divides, and review runoff and pollutant loading and removal results. The model structure, areal loading and pollutant removal calculated by the model were assessed by focusing on a number of pilot study areas within the city of Minneapolis. This paper presents model development and methodology, GIS development, and results from study areas within the city of Minneapolis.