Overview Objective Methodology Jeffrey Walker ...
A GIS-based Approach to Identify Priority Locations for Stormwater Best Management Practices in the Aberjona River Watershed Jeffrey Walker, Glennon Beresin, Laura Crossley, Yudan Jiang, Kate Olson, Shuo Zhao, Gabrielle Gareau, Anne Sexton, Ruiruo Wu, Rusty Russell and Richard Vogel Overview The Aberjona River is a major tributary to the Mystic River in the northwest metropolitan Boston area. The River suffers from urban nonpoint-source pollution, sanitary and combined sewer overflows, flooding and a long history of industrial pollution. Widespread development of the watershed has resulted in predominately suburban to highly urban land uses and extensive stormwater pollution affecting public health, recreational access and support for native ecosystems. Stormwater best management practices (BMPs) are effective tools to reduce stormwater pollution, but few methods are available for identifying optimal locations for BMPs at the watershed scale. Working in collaboration with the Mystic River Watershed Association (MyRWA) and municipal officials from four local communities, the Water: Systems, Science and Society (WSSS) Practicum team developed a novel methodology to identify priority locations for stormwater BMPs throughout the Aberjona watershed using a Geographic Information System (GIS)-based approach.
1 Sub-basin Delineation 4 Priority Sub-basin Selection
Identify 2-3 priority sub-basins for installation of stormwater BMPs based on pollutant loads and feasibility of site conditions within each community of the Aberjona River watershed.
Methodology 1
Conclusions TP Export (kg/ha/yr)
2.5
Pervious
Stormwater BMPs are known to be effective strategies for reducing pollutant loads and flooding, but selecting specific locations at the watershed scale is a complex task. We developed a GIS-based methodology to identify priority BMP locations based on estimated pollutant loads and multiple feasibility criteria. In conjunction with local knowledge of the priority areas, this approach has been useful and well-received by municipalities and will ultimately lead to more informed stormwater management programs at the community level.
Impervious
2 1.5 1 0.5 0
Data from CRWA and NES (2011)
3 Feasibility Evaluation
Sub-basin Delineation: The watershed was divided into sub-basins based on topography and stormwater pipe networks using the ArcHydro extension in ArcGIS.
2
Phosphorus Load Estimation: For each sub-basin, the annual total phosphorus load was estimated using export coefficients based on land use and impervious cover.
3
Feasibility Evaluation: Feasibility of infiltration-based BMPs was assessed based on hydrologic soil group, slope, surficial geology, and depth to groundwater.
4
An important component of this project was the direct collaboration between Tufts, MyRWA and the four municipalities. Once the priority sub-basins were selected, we met with municipal engineers and planners to incorporate additional constraints based on their expert local knowledge of each area. Future work will include detailed on-site investigations and ultimately result in the selection of one location in each community for BMP design and installation. The WSSS Practicum team is also conducting a survey aimed at gauging public awareness and perception of stormwater issues in the Aberjona River watershed. The results of the survey, GIS analysis and interviews with municipal officials will be used to generate a decision support guide designed to help municipalities continue to identify opportunities for stormwater BMP implementation in their communities.
2 Phosphorus Load Estimation
3
Objective
Community Involvement
Priority Sub-basin Selection: The sub-basins with the highest phosphorus loads and greatest feasibility were selected within each community for more detailed investigation.
Example of Priority Sub-basin
References: Charles River Watershed Association (CRWA) and Numeric Environmental Services, Inc. (NES) (2011). Total Maximum Daily Load for Nutrients in the Upper/Middle Charles River, Massachusetts. Prepared for Mass. DEP and U.S. EPA Region 1, May 2011. Partners: Mystic River Watershed Association, Bioengineering Group, City of Woburn and Towns of Burlington, Reading and Winchester Funding Sources: Massachusetts Department of Environmental Protection 604B Water Quality Management Program Funds (201101/604 ): Aberjona River Watershed BMP Development Project; Shahbazi Public Service Fund, Tisch College, Tufts University.
1 Sub-basin Delineation 4 Priority Sub-basin Selection
Identify 2-3 priority sub-basins for installation of stormwater BMPs based on pollutant loads and feasibility of site conditions within each community of the Aberjona River watershed.
Methodology 1
Conclusions TP Export (kg/ha/yr)
2.5
Pervious
Stormwater BMPs are known to be effective strategies for reducing pollutant loads and flooding, but selecting specific locations at the watershed scale is a complex task. We developed a GIS-based methodology to identify priority BMP locations based on estimated pollutant loads and multiple feasibility criteria. In conjunction with local knowledge of the priority areas, this approach has been useful and well-received by municipalities and will ultimately lead to more informed stormwater management programs at the community level.
Impervious
2 1.5 1 0.5 0
Data from CRWA and NES (2011)
3 Feasibility Evaluation
Sub-basin Delineation: The watershed was divided into sub-basins based on topography and stormwater pipe networks using the ArcHydro extension in ArcGIS.
2
Phosphorus Load Estimation: For each sub-basin, the annual total phosphorus load was estimated using export coefficients based on land use and impervious cover.
3
Feasibility Evaluation: Feasibility of infiltration-based BMPs was assessed based on hydrologic soil group, slope, surficial geology, and depth to groundwater.
4
An important component of this project was the direct collaboration between Tufts, MyRWA and the four municipalities. Once the priority sub-basins were selected, we met with municipal engineers and planners to incorporate additional constraints based on their expert local knowledge of each area. Future work will include detailed on-site investigations and ultimately result in the selection of one location in each community for BMP design and installation. The WSSS Practicum team is also conducting a survey aimed at gauging public awareness and perception of stormwater issues in the Aberjona River watershed. The results of the survey, GIS analysis and interviews with municipal officials will be used to generate a decision support guide designed to help municipalities continue to identify opportunities for stormwater BMP implementation in their communities.
2 Phosphorus Load Estimation
3
Objective
Community Involvement
Priority Sub-basin Selection: The sub-basins with the highest phosphorus loads and greatest feasibility were selected within each community for more detailed investigation.
Example of Priority Sub-basin
References: Charles River Watershed Association (CRWA) and Numeric Environmental Services, Inc. (NES) (2011). Total Maximum Daily Load for Nutrients in the Upper/Middle Charles River, Massachusetts. Prepared for Mass. DEP and U.S. EPA Region 1, May 2011. Partners: Mystic River Watershed Association, Bioengineering Group, City of Woburn and Towns of Burlington, Reading and Winchester Funding Sources: Massachusetts Department of Environmental Protection 604B Water Quality Management Program Funds (201101/604 ): Aberjona River Watershed BMP Development Project; Shahbazi Public Service Fund, Tisch College, Tufts University.
