Parts of the Chesapeake Bay watershed contain a high percentage of impervious cover – paved or other hard surfaces such as roofs and roadways that prevent rain water from being absorbed into the ground. Instead, water runs along these surfaces, collecting trash and substances such as motor oil, lawn fertilizers, and pesticides. This polluted stormwater flows into streams and rivers, where it threatens aquatic ecosystems and public health.
Effective stormwater management, on the other hand, creates safe paths for polluted runoff to be captured and filtered through the ground before it reaches waterways. This helps keep the environment clean and our communities healthy!
Project location: Annapolis, MD
Problem: The watershed of Cabin Branch Stream contains the Annapolis Mall and associated commercial areas. Due to a high concentration of impervious surfaces in this area, water quality in the stream has been deteriorating.
Solution: The nonprofit Severn RiverKeeper and its partners installed various green infrastructure practices in and around Cabin Branch Stream, including graded cascades, cobbled riffles and vegetated pools. These practices slow the flow of stormwater into the Stream, reducing erosion and allowing pollutants to filter out. This project raised and reconnected the stream bed to its original network of wetlands, significantly reducing sediment and toxic pollution in Cabin Branch Stream and its receiving waterbody, the Severn River.
Scale: 1,700 linear feet treating runoff from 144 acres
Funding sources: MD Department of the Environment; MD Department of Natural Resources’ Chesapeake and Atlantic Coastal Bays Trust Fund; National Fish & Wildlife Foundation; Watershed Assistance Collaborative (grants totaling $900,000); plus corporate grants totaling $50,000.
More information: www.severnriverkeeper.org/photo-gallery/