Multi-year effort to restore deteriorating Dyke Marsh begins

Barges are seen near Dyke Marsh, where a 1,500-foot breakwater will be built to protect the preserve. (Friends of Dyke Marsh image)

Nearly 50 years after sand and gravel mining ceased at a rare freshwater tidal marsh near Belle Haven Marina — a decades-long activity that damaged the marsh and exposed it to erosion from storm waves — the Dyke Marsh Wildlife Preserve is beginning its gradual restoration process.

In the past few weeks, a pair of barges have positioned themselves off the southern shores of the preserve — visible from the George Washington Memorial Parkway — to begin constructing a 1,500-foot breakwater designed to prevent further erosion and the eventual disappearance of the marsh, as well as to increase its resilience. According to a U.S. Geological Survey (USGS) report commissioned by the National Park Service (NPS) in 2010, Dyke Marsh’s wetlands shrunk from 183 to 84 acres during its dredging period (1940 to 1972) and by 2006 had lost another 25 percent of its acreage to erosion. The report predicted that without intervention, the marsh likely would disappear by 2035.

(USGS image)

Considering that the preserve is home to abundant plant and animal life — including six state-listed bird and plant species — its advocates are relieved that action finally is being taken.

“Dyke Marsh is a natural gem right in the backyards of many Northern Virginians who live in a region of diminishing natural resources,” said Glenda Booth, president of the Friends of Dyke Marsh, a non-profit dedicated to preserving, protecting and restoring the preserve. “Marshes or swamps are biological supermarkets and valuable natural resources.”

Over the coming weeks and months, under a $10.12 million contract with the U.S. Army Corps of Engineers, Coastal Design & Construction, Inc. of Gloucester, Virginia will place protective marine mattresses on the bottom of the Potomac and begin building a stone jetty that serves as the breakwater. That project is slated for completion in December 2019. Later this year, the Corps of Engineers will award a contract for approximately 5.45 acres of wetland restoration at Dyke Marsh, although the Virginia Marine Resources Commission has tentatively approved only 1.5 acres for restoration. Both projects are being funded by a $24.9 million grant awarded by the Department of the Interior to the NPS in 2013 as part of the Hurricane Sandy Mitigation Program.

Once complete, the Dyke Marsh restoration will provide “a storm buffer for the historic and scenic George Washington Memorial Parkway, a natural filter to clean the Potomac River, and habitat for a variety of plants and wildlife,” according to the Corps of Engineers.

While the restoration process isn’t expected to impact traffic along the Parkway, nearby residents may hear some noise. Construction activity will be suspended between February 15 and June 30, however, due to time-of-year restrictions for wildlife, said the Corps of Engineers.

Residents of the Richmond Highway corridor can continue to enjoy the Dyke Marsh Wildlife Preserve during its restoration. Besides holding bird walks every Sunday morning at 8 a.m., the Friends of Dyke Marsh will host a trash clean-up on September 22 from noon-3 p.m. Further details will be announced on the organization’s website and Facebook page.