From Gray to Green - Tools - Final Report (14-DG-11132544-102)
Transitioning to Vegetation-Based Stormwater Management
Many cities recognize the potential of Low Impact Development (LID) and green infrastructure in managing and mitigating urban stormwater runoff (e.g. nutrient load), yet most lack systematic strategies for transitioning away from their existing conventional (gray) drainage systems. This project developed an open-source, decision support tool (DST) to aid the strategic planning process for transitioning to LID Best Management Practice (BMP) systems that emphasize trees and urban forests. The toolset is designed to be easy to use by natural resource managers, planners, and engineers, using nationally available and locally relevant datasets. It relies on four step planning processes that involve 1) Mapping of existing hydrology and green infrastructure, 2) designing and fitting a development/redevelopment project to the site, 3) selecting appropriate green infrastructure BMPs for the site, and 4) evaluating how well the project and BMPs fit the site. The tool includes a GIS-based mapping tool to identify areas suitable for green infrastructure, and an optimization tool to identify and select an optimal mix of existing gray and new green infrastructure to achieve runoff quantity and quality goals. The tool is supplemented with supporting documentation, including case studies that were carried out in Tampa (Florida) and Milwaukee (Wisconsin).
ufs - drh