Edmonston, Maryland Green Streets Project
Edmonston, a small town near Washington DC in Prince George’s County, MD, created a “green street” to address previous problems with flooding on Decatur Street near the Anacostia River. The town wanted to better manage that flooding and improve water quality, as well as to manage traffic by narrowing the street. The project utilizes a variety of green infrastructure tools to reduce stormwater runoff, thereby decreasing the amount of polluted water that enters the Anacostia River. While the project does not specifically reference climate change as a motivation, the methodology and considerations for this project, could be useful for a jurisdiction that will experience heavier precipitation due to climate change.
The Maryland standard for stormwater requires capture of 1 inch of rainfall on 50% of impervious surfaces. Edmonston wanted Decatur Street to capture 1.33 inches on 90% of impervious surfaces. The city considered many green infrastructure strategies including bioretention cells, street trees, and others. The final design included rain gardens, bioretention cells, street trees, and permeable pavement in the bike lanes. On average, the rain gardens treat 62% of the stormwater, and permeable pavement another 28%, for a total of 90% of rainfall completely filtered.
The Town made space for these improvements not by widening the road, but by narrowing the vehicle lanes, gaining room for sidewalks, bike lanes, and rain gardens. This also decreased the total impervious surface. However, since construction, the roadway has suffered damage from large trucks using Decatur Street; their weight has made the street deteriorate more quickly than it should.
The project was paid for with federal American Reinvestment and Recovery Act (ARRA) money; initial seed money from the Chesapeake Bay Trust paid for a report on design options from the Low Impact Development Center.
This Adaptation Clearinghouse entry was prepared with support from the Federal Highway Administration. This entry was last updated on June 11, 2015.
Publication Date: 2010
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