Mallows Bay-Potomac River National Marine Sanctuary

NOAA has designated an 18-square mile stretch of Maryland’s Potomac River Mallows Bay-Potomac River National Marine Sanctuary. It is the first national marine sanctuary designated since 2000 and protects the remnants of 118 World War I-era wooden steamships and vessels as well as other significant maritime heritage resources.


The state of Maryland nominated the area for sanctuary designation in 2014 to protect and conserve the shipwrecks and cultural heritage resources, as well as to foster education and research partnerships, and to increase opportunities for public access, tourism and economic development. The nomination enjoyed broad community support as well as strong support from the Maryland congressional delegation.

Mallows Bay is most renowned for its “Ghost Fleet,” the partially submerged remains of more than 100 wooden steamships that were built in response to threats from World War I-era German U-boats that were sinking ships in the Atlantic. Although the ships never saw action during the war, their construction at more than 40 shipyards in 17 states reflected the massive national wartime effort that drove the expansion and economic development of communities and related maritime service industries. The fleet was brought to the Potomac River to be salvaged for scrap metal by a company in Alexandria, Virginia, not far from the sanctuary site.

The sanctuary was formally designated on September 3, 2019, following 45 days of continuous congressional session after publication in the Federal Register on July 8. NOAA, the State of Maryland, and Charles County will manage the national marine sanctuary jointly.

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Resources present: Includes 118 WWI-era U.S. Emergency Fleet Corporation steamships; Maryland Indian Tribes heritage sites; remains of historical fisheries operations such as sturgeon and caviar industries; and Revolutionary and Civil War battlescapes.

Boundaries: Boundaries coincide with the Mallows Bay Widewater Historical and Archeological National Register District

Approximate total area: 18 square miles

Mallows Bay Park address:
1440 Wilson Landing Road
Nanjemoy MD 20662

For more information contact
Paul Orlando
Chesapeake Bay Regional Coordinator
ONMS Northeast and Great Lakes Region

NOAA's National Marine Sanctuary System

The Office of National Marine Sanctuaries serves as the trustee for a network of underwater parks encompassing more than 600,000 square miles of marine and Great Lakes waters from Washington state to the Florida Keys, and from Lake Huron to American Samoa. The network includes a system of 14 national marine sanctuaries and Papahānaumokuākea and Rose Atoll marine national monuments.

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