Living Shorelines Are Hurricane Strong in North Carolina
Monitoring a living shoreline after a storm. Photos courtesy of the North Carolina Reserve.
At our North Carolina Reserve, the results are in—shorelines that incorporate natural landscape features can be an effective way to stabilize coastal areas as storms become more severe and frequent around the country.
Working with their state partner, the North Carolina Division of Coastal Management, Reserve scientists are monitoring the effectiveness and durability of rock and oyster sills at eight sites spread over more than 200 miles of the state’s coastline. Marsh sills are a form of living shoreline that uses oyster shell or rock to protect existing or newly planted marsh vegetation. They run parallel to the shore, reducing the wave energy hitting the marsh. In turn, the marsh also reduces wave energy and erosion further upland.
Living shorelines built with oyster shells stabilize the shoreline and provide critical habitat.
For this project, the team visited each site before and after Hurricane Florence in 2018. Their data showed minimal signs of erosion, marsh vegetation loss, or damage to the sill.
“The results have been remarkable,” says Brandon Puckett, the Reserve’s research coordinator. “Monitoring pre- and post-Hurricane Florence demonstrated that all of these living shorelines are extremely resilient. The land behind the sills experienced minimal erosion—less than a foot —despite the strength of the storm.”
At the St. James Plantation retirement community in Southport, there’s no doubt that their living shoreline is creating value. For locals, their 505-foot sill is not just bags of rocks and oysters, it is also something that brings the community together. Each year, a group of more than 30 high school students come out to expand and repair the sill as needed, while learning about the science behind it and the benefits it offers.
High school students from the University of North Carolina Wilmington Oceans 17 youth program install marsh grass on the living shoreline with retirees from the local community.
“Our living shoreline is a multigenerational program,” says Taylor Ryan, the St. James resident who spearheaded the installation of the shoreline in 2007. “It’s great for us to have the young people come in and help– and they love helping on a project that they can see real results from. And the community members bring their grandkids too, and get them involved.”
The project team is using their data to advise property owners, contractors, regulatory partners, and others engaged in shoreline management. For example, research results are being incorporated into Promoting Living Shorelines for Erosion Control workshops organized by the Reserve’s Coastal Training Program. The team also shared their findings with the Coastal Resources Commission, which establishes policies for North Carolina’s Coastal Management Program, including those related to dredging and filling along the coasts.
Puckett says, “The data on the favorable performance of these sills can be used to demonstrate their benefits, durability, and potential cost-effectiveness to someone looking to install a new living shoreline. We’ll continue to monitor these sites for the next three to five years to see how quickly these shorelines recover from the minimal damage incurred from the storm.”