Dumfries, VA – Restoration to improve the resiliency of the Possum Point Road culvert – located on Route 633 at the Prince William County and Town of Dumfries line – over Dewey’s Creek has wrapped up after nearly three months of work, interrupted by frequent heavy rainfalls and storms. Dewey’s Creek is a tributary of Quantico Creek, which is a tidal tributary of the Potomac River.
The restoration will improve sediment transport, water flow and fish habitat. In addition, it will reduce flood risk to the surrounding community, which includes approximately 50 homes southeast of the culvert as well as the Possum Point Power Station, located on the banks of the Potomac River and serving the Washington, DC, metropolitan area and.
Growing development within the watershed has increased the risk of culvert failure. Storm water runoff from paved surfaces and yards causes flows to increase in the creek, leading to erosion, increased sediment accumulation at the culvert and constriction of water flow during high flow conditions.
“This culvert has a history of over-topping. High water during Hurricane Sandy in 2012 led to highway flooding,” said Albert Spells, USFWS project leader in Virginia. “To avoid similar problems in the future, we determined that the best strategy would be a stream restoration approach.”
Instead of replacing the culvert with something larger, the project involved restoring Dewey’s Creek for approximately 400 feet above the culvert. Stream banks were sloped and terraced to reconnect the creek to its floodplain, while rock elevation controls and riffles were constructed to eliminate sediment build-up at the culvert’s entrance and improve water flow and fish habitat.
“Access to upstream nursery habitat will be improved for American eel, as well as downstream passage through the culvert for silver eels migrating from the creek to their spawning site in the Sargasso Sea after having utilized the creek as a nursery for 3 to 18 years,” continued Spells. “American eel has long been recreationally and commercially important, as well as ecologically as a prey source for other fish and wildlife. In addition, habitat will be substantially improved for resident fish in the restored area above the culvert.”
The only freshwater eel species in North America, the American eel is migratory and leaves its habitat to enter the Atlantic Ocean during its spawning migration. The eels’ reproductive success relies heavily on open passage during migration to complete their lifecycle and ample diverse habitat for growth and maturation.
Coastal habitats, wetlands, and beaches will ultimately benefit from the upstream and inland-sources of sediment nourishment that will come from restoring natural sediment transport, flood storage and increased channel flow capacity of the creek.
The return on investment, both for conserving American eel and avoiding potential emergency repairs and safety concerns, is estimated at $3.13 million for the Prince William County and Town of Dumfries community. The project itself is one phase of a larger effort by Prince William County to restore Dewey’s Creek upstream of the culvert as well.
“This project would not have been possible without the assist of a grant,” said Terry Myers, Town of Dumfries Acting Public Works Director. “The Town of Dumfries’ budget would not be capable of supporting a project of this size and scope.”
The $330,750 project was funded by the U.S. Fish and Wildlife Service through the Hurricane Sandy Disaster Relief Act of 2013. Partners on the project include the U.S. Fish and Wildlife Service, American Rivers, and both the Town of Dumfries and Prince William County. The Fish and Wildlife Service provided a $297,000 grant to the Town of Dumfries to do the work. Staff from the Prince William County’s Public Works Department acquired the project designs and engaged the contractor for the project. Prince William County has contributed over $300,000 toward the project.
To read more about the coastal restoration project, click here. To view photos of the project, click here. To learn more about other U.S. Fish and Wildlife Service Hurricane Sandy recovery and resilience projects, visit the Hurricane Sandy Recovery website.
