PROJECT OVERVIEW/BACKGROUND:

In Washington, DC, stormwater runoff is a major source of pollution to the Anacostia and Potomac Rivers, and Rock Creek, and causes flooding that negatively affects local residents and businesses. DC also is ranked as one of the top five urban areas on the US East and Gulf Coasts where increased flooding is expected to impose significant risk to infrastructure due to predicted and observed climate change effects. The combination of more intense rain events and sea level rise is expected to increase the frequency and magnitude of flooding across DC and in the Anacostia River watershed. In addition, stormwater represents a major and growing source of pollution to the Chesapeake Bay watershed.

The Nature Conservancy recognizes the potential for green infrastructure to mitigate impacts of development and climate change while also improving the quality of life in urban areas. Identifying and prioritizing opportunities, however, remains a significant challenge in the face of limited resources. For these reasons, the Maryland/District of Columbia (MD/DC) Chapter of The Nature Conservancy (TNC) invites proposals for development of a map and database of existing stormwater retention projects, and a map and database of the potential for future stormwater retention projects. This report will:

Develop a geodatabase of existing Green stormwater Infrastructure (GI) best management practices (BMPs) that are recognized in the District Department of Energy and the Environment (DOEE) Stormwater Management Guidebook, specifically limited to trees, bioretention, wetlands, and bioswales, throughout the Anacostia River watershed within Washington, DC, including: location and date of implementation, intended environmental and social benefits, businesses and population demographics around the GI prior to implementation and currently.
Identify locations that are high priority sites needing stormwater retention because of high environmental impact from pollution levels and land use practices onsite that result in high quantities and low quality of stormwater runoff (measured in gallons and pollution loads).
Identify locations that are currently subject to localized and tidal flooding, and locations that are projected to be impacted from flooding brought on by climate change, property damage from flooding, and population demographics and businesses around those locations.
Recommend the type of BMP and location of green infrastructure projects that could be implemented to retain stormwater runoff from prioritized sites and abate current and projected stormwater flooding impacts.

This information will be used to map opportunities to implement new green infrastructure in Washington, DC to retain stormwater runoff and reduce flooding. This information will provide clarity on where stormwater retention services from GI exists, and the gap of services where TNC should focus efforts to implement future GI projects to have environmental and social benefits across diverse socioeconomic demographics in the watershed. This report will also be made publicly available so that others can view it and identify the best places to implement projects that will have the highest benefits for nature and people.

More information and contact available here: The Nature Conservancy – DC Urban Stormwater Baseline Data RFP