Upper St. Mary’s River Restoration

Large-scale restoration efforts began in 2021 in the Upper St. Marys River sanctuary. The initial implementation phase of the restoration project was completed in 2022, with a total of 60.2 acres of reef restored.​

  • The restoration plan for the Upper St. Marys River may be found here​.
  • The pre-construction groundtruthing report can be found here​.

Below is an interactive map with potential restoration reefs in the St. Marys Sanctuary. The legend and layers are located in the upper right-hand corner. You can click on a reef to see more information. The information was last updated in January 2022.

Restoration sites are identified as ‘seed only’ restoration (hatchery-produced spat-on-shell added to existing remnant reefs) or ‘substrate + seed’ restoration (adding reef-building substrate to the reef footprint, followed by planting with hatchery-produced spat-on-shell) or ‘premet’ (sites that already meet the Oyster Metrics target oyster density (50+ oysters per m2) and oyster biomass (50+ grams per m2) and not slated to receive initial restoration).


Three-year and six-year monitoring efforts are used to assess the oyster metrics for each reef. The first three-year monitoring has yet to occur.


Upper St. Marys River Restoration Reefs


Below is an interactive map with thepotential restoration reefs in the St. Marys Sanctuary. The legend and layers are located in the upper right-hand corner. You can click on a reef to see more information. The information was last updated in March 2023.
Restoration sites are identified as ‘seed only’ restoration (hatchery-produced spat-on-shell added to existing remnant reefs) or ‘substrate + seed’ restoration (adding reef-building substrate to the reef footprint, followed by planting with hatchery-produced spat-on-shell) or ‘premet’ (sites that already meet the Oyster Metrics target oyster density (50+ oysters per m2) and oyster biomass (50+ grams per m2) and not slated to receive initial restoration).