When Hurricane Sandy hit in October of 2012, it wreaked havoc on states along the eastern seaboard.
Chincoteague Island, which is located in Virginia’s Eastern Shore region, was just one of the coastal communities that felt the impact of the storm’s tidal surge.
“There were a lot of areas that were scoured from the impacts of the water,” explained Kevin Holcomb, a wildlife biologist with the U.S. Fish and Wildlife Service.
Since then, the U.S. Fish and Wildlife Service has partnered with The Nature Conservancy and the Virginia Marine Resources Commission in an effort to build a “living shoreline.”In 2016, a total of 13,750 oyster castles were installed at two sites at the Chincoteague National Wildlife Refuge, thanks to resilience funding provided by the Department of the Interior.
At a distance, they could easily be mistaken for a series of sandcastles. The difference is, these castles are dampening the energy of the waves that are approaching the shore.
“The castles are 30-pounds, [and] essentially they look kind of like cinder blocks, only they’re one foot by one foot,” said Jenny Miller, with The Nature Conservancy.
The four-pronged concrete blocks can be stacked on top of one another in a variety of different ways. The North Wash Flats and the Tom’s Cove sites both have two staggered rows of oyster castles, each of which consists of 28 blocks.
“The castles that we have now, provide a substrate for the oyster spat to stick to then grow upon,” Holcomb said.
As oysters grow on the castles, they help prevent erosion to the area’s salt marshes, which are, in turn, protecting the mainland.
“If you have a healthy marsh on the shoreline, then the marsh is helping to absorb flooding water or to slow a wave that’s approaching,” explained Cristina Carollo, a senior coastal scientist at The Nature Conservancy. “So it’s a natural feature that is protecting our communities.”
Carollo said the hope is that these oyster castles will be able to keep pace with rising sea levels. Oftentimes what’s called “gray infrastructure,” or human-engineered solutions, are implemented to protect the shoreline. But Carollo said the big difference between installing a revetment wall, which is a form of gray infrastructure, versus something like the oyster castles, is that the wall is static.
“If you build a wall that’s six feet, unless you go back and build it higher, then that’s the height of the wall,” Carollo said. “The wall is not going to grow on its own.”
Instead, she said investing in a living shoreline is much more beneficial because it grows on its own and provides a habitat for other marine life.
Holcomb said he hopes this gives the public an opportunity to see what oyster castles are and how they grow so they can mimic the project in their own coastal areas.
“I think that the most important thing is that we are working toward making our coastal community more resilient,” Carollo added. “That’s what it comes down to for me.”
At this point, Holcomb said they are still monitoring the rate of erosion behind the oyster castles to see just how well they work. Miller added that they’re already starting to see saltmarsh cordgrass growing behind the castles, which could be a good sign.
“There aren’t any numbers and research and statistics yet to say how much they have helped, but you can definitely see visually that it’s kind of building the marsh up there, which is just another benefit of having the oyster castles,” she said.