Oyster Reef’er Madness

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The Severn River is seriously compromised!

For thousands of years, oysters thrived in the Severn. They had a strong effect on the nature of the river itself, creating fisheries and influencing human life along these shores.

Fast forward to today – over harvesting, pollution, stormwater runoff, and increased erosion and silt from development have created profound biological change. Fish kills, dead zones, and harmful algae blooms are now common occurrences.

To address the problem, the Severn River Association and key partners have launched Oyster Reef’er Madness!


Our long-term goal is to plant 1.3 billion oysters in the Severn River.

Each oyster is like a small water-treatment plant, filtering up to 50 gallons of water per day! And, oyster reefs create the structure and habitat for other marine life to thrive, and improve fishing on the river. 

Our team of scientists, watermen, divers and volunteers are replanting oysters all along the river. A major focus for 2018 is to re-establish oyster reefs between the Rt. 50 and U.S. Naval Academy Bridges.

Operation Build-A-Reef Takes Off

To jump start this effort, SRA has partnered with the Oyster Recovery Partnership (ORP) to create Operation Build-A-Reef to restore historic oyster reefs between the Rt. 50 and U. S. Naval Academy bridges outside Weems Creek.

Here’s where the partnership is planting oysters.

The red area that SRA board member John Page Williams is pointing to is an oyster bar known as “Weems Upper.” This is one of four oyster reefs between the two bridges that the SRA/ORP partnership is restoring.

In 2018, the Build-A-Reef partners leveraged support from the Maryland Department of Natural Resources with private donations to purchase 50 million oyster spat-on-shell from the Horn Point Hatchery in Cambridge, Md.

The spat were shipped up to the Severn River on the oyster planting vessel, the Robert Lee, which planted the spat-on-shell in four trips to the Severn River. To the left is the the Robert Lee in action.

The Capital newspaper provided excellent coverage of the first day of planting. Click here to read the article, watch their video and check out some pictures of the July 23, 2018 event.

The oyster reefs selected for restoration were chosen because the have firm substrate on the river bottom that oysters can easily attach to and get to work cleaning the river.

Plans are already underway to plant millions more oyster spat-on-shell in the summer of 2019.  We plan to continually monitor progress and see how well the oysters are doing.

Ultimately, it will take billions of oysters to filter the entire river – from the mouth to the headwaters.

With your support, we can restore one of nature’s hardest working species and let them do what they do best – filter the water so that the Severn and its inhabitants can thrive now and into the future!

One day we’ll reach our goal to have 1.3 billion oysters filtering and cleaning the Severn River every day!


Severn River Association, Oyster Recovery Partnership, Maryland Department of Natural Resources, University of Maryland’s Horn Point Hatchery, and Chesapeake Bay Foundation.


Program Goal

Improve water quality to create a resilient reef habitat by planting and monitoring oysters that will perform their natural, historic function – to filter the water.

Program Outcome

  • Enhance conditions for fishing, swimming, crabbing, and other recreational activities.
  • Raise public awareness about the land-river connection.
  • Educate the public about ways to improve the river ecosystem
  • Improve and increase marine life (finfish and shellfish) habitat.
P.O. Box 146 | Annapolis, Maryland 21404 | phone: 443-569-3556 | email: