Community-based oyster restoration

Local volunteers come together to help defend a vulnerable coastal town

A Town in Need

The Town of Wachapreague, one of the last fishing communities left on Virginia's Eastern Shore, is protected from the sea by a system of barrier islands and marshes, where marshes are the last natural defense to storms and rising seas. As a result of climate change, protective saltmarshes are eroding, and flooding events are becoming more frequent. Without maintaining broad saltmarshes to diminish wave energy, the town will be more vulnerable to storms in the future.


The Little Marsh Island

A Little Marsh Island just seaward of Wachapreague acts as a first line of defense by buffering wind waves reaching the town.

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However, aerial photographs have documented significant areal reduction of the Little Marsh Island over the last 30 years.

In an effort to slow erosion of the Little Marsh Island and help protect Wachapreague, this site was selected as a site for oyster reef restoration, a nature-based solution for coastal protection that stabilizes shorelines and enhances oyster populations and the ecosystem services they provide.


Artificial Oyster Reefs

For the reef restoration project, the shoreline of the Little Marsh Island was divided into 9 sections that were treated with different oyster substrate designs, including oyster castles and the novel Oyster Catcher™ substrate, that act as a hard surface for oyster larvae to attach and grow on.

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Section 1 - oyster castles

The oyster castles in this project are notched concrete blocks developed by Allied Concrete, Inc. in Charlottesville, VA. The castles are designed to latch together to create vertical structures that provide both resistance against daily wave energy and a hard surface for larvae to attach and grow on. This substrate is ideal for flat, hard bottom areas.

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Section 2 - Oyster Catcher™

Sandbar Oyster Company© has developed an alternative oyster substrate design, Oyster Catcher TM  , that was created for conditions in which oyster castles are less suitable. This design consists of biodegradable hardscapes composed of plant fiber cloths with mineral-based binders that are wetted with concrete and formed into different shapes and sizes.

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Section 3 - Oyster Catcher™

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Section 4 - Oyster Catcher™ and oyster castles

This part of the marsh consisted of both soft/muddy and sandy/hard bottom areas, so we used a combination of oyster castles and Oyster Catcher™. Placing the oyster castles closest to the waters edge added an extra layer of protection to Oyster Catcher™ and the marsh.

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Section 5 - oyster castles

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Section 6 - oyster castles

Here, castle walls were built up against the marsh and pyramid shapes were placed on the exposed mud flat to add an extra layer of defense from daily wave energy.

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Section 7 - oyster castles

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Section 8 - Oyster Catcher™

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Section 9 - Oyster Catcher™

Volunteers at Work

Volunteers were often found loading oyster castles onto the boat for transport to the Little Marsh Island.

Once they reached the Little Marsh Island, oyster castles were offloaded and configured into walls.

Meanwhile, back at Brownsville Preserve, volunteers had their hand at making Sandbar Oyster Company's Oyster Catcher TM  substrate.

This substrate is created by soaking jute fiber cloth in concrete and molding into different shapes and sizes.

This substrate was later placed along the shoreline of the Little Marsh Island.

Project Success

From May 2020 to November 2023, 2,174 volunteer hours were recorded,

10,000 oyster castles were deployed,

and 1,600 Oyster Catcher TM  pieces were constructed for a total of over 2,000 ft of shoreline restored.

The oyster castles fostered incredible oyster attachment and growth...

and so did the Sandbar substrate!

The constructed reefs increased shoreline protection by dampening shallow water wave energy reaching the Little Marsh Island and...

reducing marsh edge erosion. Before reef restoration, shoreline retreat occurred at a much higher rate. For example, this pole is marking the edge of the shoreline only a few months prior to when the photo was taken. After the reefs were constructed, erosion significantly slowed.


The Coastal Resilience Tool

The Coastal Resilience (CR) Decision-Support Tool is an innovative web-mapping portal developed by TNC that empowers people to assess coastal risks and vulnerability and identify a range of strategies for reducing these risks and enhancing resilience using nature-based solutions (NBS).

Virginia Coastal_Resilience Tool

This project in Wachapreague is an example of how alternative substrate restoration can be used to inform the Tool for decision making purposes in an effort to help protect coastal communities from threats associated with sea level rise.

Project Collaborators

This project was funded by the National Fish and Wildlife (NFWF) Federation grant #65706.