Work remains in one river before meeting the Chesapeake Bay Watershed Agreement outcome to restore oyster reefs in 10 tributaries by 2025
The Chesapeake Bay Program is pleased to release their annual update of oyster reef restoration efforts, detailing progress made in 2024 toward the world’s largest oyster reef restoration project. Since the Chesapeake Bay Watershed Agreement was signed in 2014, organizations in Maryland and Virginia have collaborated to successfully restore oyster reefs in nine Chesapeake Bay tributaries in order to enhance habitat, which in turn supports the ecosystem and economy.
Restoration work on the 10th tributary—the Manokin River on Maryland’s Eastern Shore—is expected to be completed within the near future. With 441 acres restored of this oyster reef, Chesapeake Bay Program partners will have fulfilled the commitment in the 2014 Chesapeake Bay Watershed Agreement to restore oyster reef restoration in 10 Bay tributaries by 2025.
This will meet Maryland’s goal of restoring oyster reefs in five tributaries by 2025. Virginia recently reached the same milestone by completing restoration in the Lynnhaven River in the spring of 2025. Overall, partners have restored 2,294 acres toward the planned acres. That is more than 2.76 square miles—or 1,340 football fields—of vibrant habitat.
“We are incredibly pleased to have not only met, but exceeded, our oyster restoration goal,” said Virginia Secretary of Natural and Historic Resources Stefanie Taillon. “These results are a tremendous example of the power of a voluntary, partnership-driven approach to achieving a vibrant and healthy Chesapeake Bay. As we look to the future of the Chesapeake Bay Watershed Agreement, Virginia remains committed to working with partners to establish and implement realistic strategies for ensuring sustainable oyster population and habitat.”
The 2024 Chesapeake Bay Oyster Restoration Update shows the following for each tributary:
| Tributary | Tributary Restoration Plan | Reef Construction and Seeding | Monitoring and Evaluation | Completed/Target Acreage (including pre-existing healthy reef acreage) |
| Harris Creek (Md.) | Complete | Complete | Complete | 343/343 |
| Little Choptank (Md.) | Complete | Complete | In-Progress | 358/358 |
| Tred Avon (Md.) | Complete | Complete | In-Progress | 131/130 |
| Upper St Mary’s (Md.) | Complete | Complete | In-Progress | 60/60 |
| Manokin (Md.) | Complete | In-Progress | In-Progress | 345/441 |
| Lafayette (Va.) | Complete | Complete | In-Progress | 82/82 |
| Piankatank (Va.) | Complete | Complete | In-Progress | 497/444 |
| Lynnhaven (Va.) | Complete | Complete | In-Progress | 126/152* |
| Lower York (Va.) | Complete | Complete | In-Progress | 204/200 |
| Great Wicomico (Va.) | Complete | Complete | In-Progress | 124/124 |
| Eastern Branch of the Elizabeth River (Va.)** | N/A | Complete | In-Progress | 24/20 |
*Restoration was completed for the Lynnhaven River in spring 2025; this chart reflects updates as of December 31, 2024.
**The Eastern Branch of the Elizabeth River is an 11th “bonus” tributary established by Virginia in 2019.
After each tributary was selected for restoration, scientists developed a strategy to guide the process of constructing and seeding reefs, as well as monitoring and evaluating their progress. Monitoring and evaluation take place at three-and-six-year intervals, which will continue beyond 2025. Planning and implementing this work has been coordinated by the Maryland and Virginia Oyster Restoration Interagency Teams.
“Maryland made a commitment to restore oyster habitat through the Chesapeake Bay Watershed Agreement,” said Maryland Department of Natural Resources Secretary Josh Kurtz, who serves as the chair of the Principals’ Staff Committee for the Chesapeake Bay Program. “We delivered on that commitment through strong support from the Chesapeake Bay Program, NOAA, Army Corps of Engineers, Virginia and local organizations. During the previous decade, this work, favorable environmental conditions and effective management of the oyster fishery has helped Maryland triple the estimated population of oysters in our portion of the Bay. This success story shows the power of effective habitat restoration for one of the Chesapeake Bay’s most important species.”
Monitoring Tracks Success of Restored Reefs
Monitoring is critical in determining the overall success of the restoration by tracking the recruitment of new oysters, survival rate during the early planting stages, natural mortality, disease status, growth, reproduction and shell accumulation. The most recent monitoring report shows that 98% of 681 acres in Maryland that were monitored between 2015—2023 met the basic threshold level for success, while 83% met higher target levels, which included having more than 50 oysters per square meter. Monitoring results from 2024 are still being analyzed, although preliminary results show a similar positive trend.
Restored reefs in Virginia also show success. In the Lynnhaven River, monitoring data shows about 3,400 oysters per square meter ( a combination of spat/juvenile oysters and adults) on restored reefs. This indicates that healthy oyster reef habitat is attracting new generations of oysters. In the Piankatank River, an average of 425 oysters (spat and adults) were found per square meter on restored reefs. Surveys conducted in 2024 confirmed the reefs are doing as well or better than in 2019 and are expected be self-sustaining over the long-term.
These flourishing reefs provide important economic and environmental benefits. Oysters are ecologically valuable as filter feeders that help clean the waters of the Chesapeake Bay and its tidal tributaries by pumping water through their gills and trapping food particles, nitrogen, phosphorus, sediment and chemical contaminants. Under certain conditions, an adult oyster can filter up to 50 gallons of water per day. In some situations, they can protect shorelines from wave erosion, helping communities to prepare for some of the disruptions that extreme weather may cause.
Since the late 19th century, the oyster industry—including the catch, sale, shucking, packing and shipping of oysters—has contributed hundreds of millions of dollars to the region’s economy. Oyster reefs also attract other species that support commercially and recreationally important fisheries. For example, studies have shown the reefs can bolster the economic benefits of the blue crab fishery.
The Future of Oyster Reefs in the Chesapeake Bay Watershed Agreement
For more than a decade, Chesapeake Bay Program partners have been working toward restoring oyster reefs in support of the Oysters Outcome in the 2014 Chesapeake Bay Watershed Agreement. The partnership is now working to update and revise the Watershed Agreement to guide future restoration efforts.
As oysters and oyster reefs support the Chesapeake’s ecosystem and economy, efforts related to oysters will be included in the revised Watershed Agreement. The public is invited to provide feedback on the proposed Oysters Outcome, along with the rest of the draft Watershed Agreement through Monday, September 1, 2025 by emailing [email protected]. For the most up-to-date information on the process to revise the Chesapeake Bay Watershed Agreement, please visit the Chesapeake Bay Program’s Planning for 2025 and Beyond website.
Rachel Felver, Chesapeake Bay Program Communications Director.
