VIRGINIA BEACH, Va. (WAVY) — It’s been just over two years since 10 On Your Side’s Andy Fox brought attention to a large mountain of concrete in Virginia Beach.

The mountain started to dwindle over time, but where was it all going?

As it turns out, there was an organization looking for a surplus of concrete to do some good with.

Lynnhaven River Now, for the first time ever, is using recycled concrete from all over the city to lay in the Lynnhaven Inlet near the Lesner Bridge in order to rehab the oyster population.

Volunteers are using old fireboats with firehoses to blow the recycled concrete into the water off of a barge navigating through very delicate, sometimes shallow, waters. After the artificial reefs are a foot tall, baby oysters attached to oyster shells will be added on top.

“It creates a substrate for the oysters to settle on and then create more oysters,” explained volunteer Brent James. “It’s a substitute for oyster shells, which are in very rare supply these days.”

With their natural foundation hard to come by, the oysters started to decrease in population. James says overfishing and different diseases brought numbers into a plummeting spiral.

He says the conversation is much larger than just bringing back the oysters, but preserving the ecosystem they create for other species around them.

“We call the oyster the ‘keystone’ species in the Chesapeake Bay, in the whole region, because it provides interstitial spaces where the small shrimp, crabs, and baby fish, and everything can hide from the predators,” said James. “All the species benefit from having the oysters here.”

Perhaps an even more incredible function is the oyster’s ability to filter our waters.

“Oysters do two things: they filter the water, primarily of nitrogen and phosphorus, which are the two main pollutants that contribute to algae blooms,” he said. “In a laboratory situation, an oyster can filter up to 50 gallons of water a day. Out in the wild? Usually, 5 to 20 gallons is a more reasonable number but multiplied by millions and millions of oysters.”

These days, that’s hard to imagine with the low population. That’s why LNR is trying to create new habitats for shellfish.

“We have an 11-acre site that we’re creating oyster reefs on as part of the 2014 Chesapeake Bay Agreement. We’re supposed to have 152 acres of oyster reef in the Lynnhaven and this will contribute to that,” said James.

The agreement established goals and outcomes for the restoration of the Bay, its tributaries, and the lands surrounding them. This particular project working towards the goals of the bay was made possible by a partnership with the Chesapeake Bay Foundation and grants from the National Fish and Wildlife Foundation.

Two of the reefs being created are in the Pleasure House Creek. They are scheduled to be finished in the next couple of months. The third is in the Eastern and Western Branches of the Lynnhaven River and should be completed later this spring.

At the daily mercy of the tides, volunteers know the work isn’t easy or convenient. Still, they work around the clock to undo the damage done to our local waterways.

“It took generations to create the problem, it will take generations to solve it,” said James.

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