TMDL Development from the “Bottom Up” – Part V: Pilot Efforts to Strengthen Storm Water BMP Implementation in the Upper Midwest

A challenge facing many local jurisdictions across the country is finding ways to connect Storm Water Management Programs (SWMPs) required by NPDES permits with TMDLs intended to address water quality problems. A “bottom up” approach towards TMDL development that utilizes local watershed planning activities is one way to establish a meaningful, value-added framework. A “bottom up” approach enables water quality concerns to be linked with proposed solutions. Information on Best Management Practices (BMPs) related to both source control and delivery reduction methods can be incorporated into TMDL allocations. Management measure information considered in TMDL allocations can then complement benchmarks that guide implementation efforts.In order to take advantage of local watershed protection efforts, USEPA Region 5 initiated three storm water TMDL pilot projects in Michigan, Indiana, and Minnesota. The intent of these pilots is to use emerging BMP targeting and optimization information coupled with local experience to advance working knowledge of methods that strengthen the connection between TMDLs and storm water management program implementation.The areas being studied as part of the Region 5 pilot watersheds all include waters on state §303(d) lists for impaired biological communities. Individually, each watershed also has other unique causes responsible for their placement on the list, ranging from a suite of toxic pollutants to more traditional bacteria and nutrient concerns. One pilot watershed has been subjected to numerous legacy sources of toxic pollutants. It also receives runoff from urban, residential, and agricultural land uses in the area. Another pilot is currently experiencing rapid development, which compounds problems associated with existing land use in the watershed. The hydrology in this area has been significantly altered, including substantial wetland losses. The third pilot watershed is in a highly urbanized, metropolitan area that spans a multitude of local jurisdictions.The pilots collectively include a wide array of implementation programs to address storm water sources that contribute to water quality problems. In one case, a regional planning commission completed a water quality management plan for the larger area and is working with the city in their efforts to develop a Storm Water Management Program. Parts of the watershed are also currently undergoing redevelopment under the Brownfields program. Another pilot will build off a locally prepared watershed management plan that emphasizes low impact development and wetlands restoration. A key local organization has been an active player in education and outreach programs within the watershed, as well as efforts to design and implement targeted storm water BMPs that address water quality problems.Using the TMDL technical assessments to strengthen storm water BMP targeting and implementation is a common objective for all three pilot efforts. Models are used to identify hydrologic targets that also serve as watershed and sub-watershed benchmarks for BMP performance. Information on BMP effectiveness will be coupled with cost information to identify the most economical options through an optimization step. The goal is to target specific implementation activities that address each pilot watershed's water quality problems related to storm water.