WHQR's Michelle Bliss caught a boat ride to the mouth of Mill Creek to see those shells put to use.
Marine Biologist Pat Donovan-Potts is leading a couple dozen volunteers as they stack hundreds of 10 lb, mesh plastic bags of shells, creating a protective wall around the eroded tips of an unnamed island.
Everyone's moving swiftly, so their mud boots don't sink in the sludge of the boggy creek bed.
"Pack them down. Take the end with the hog tie on it. Wrap it underneath. You want these packed in here as tight as possible because the first high tide that comes in here, we're going to get a lot of boat or wave action and we don't want energy to move these bags around."
While these volunteers build the reefs, others are on land, loading oyster shells onto boats and barges to drop them off on the island.
They have just a few hours to work before the tide rolls in over the two-acre tract of delicate wetland. Only a smattering of shells and the bright green blades of protected sea grasses, like eel grass and ruppia, will remain above water.
"You see the cove over there, there used to be nothing but grasses. You see the mud with the grasses on top. It used to come all the way over here. All of that has eroded away in one year's time."
Pat's pointing to an area the new reefs are designed to protect. Heavy boat traffic from the Intracoastal Waterway has eroded the spot by about 20 feet since last summer.
In less than an hour, UNC Wilmington Senior Research Associate Troy Alphin has heard 50 boats cruise by, churning the water into heavy ripples.
"Those boat wakes, none of them are huge, but it's a constant, constant erosive force. Put these shell bags out here and build these small reefs and for relatively small amount of structure, you get a huge amount of protection for the marshes on the back side."
The primary function of the reefs will be erosion-control, but Alphin says there are a host of other benefits, like water filtration.
"Oysters provide habitat for other organisms including oysters, mussels, small fish, things of that nature. As they pull material out of the water column, they deposit stuff that isn't food quality into the sediment, so that bacteria can break it down. So, they contribute to the nutrient cycling."
The bags are stacked in a three-two-one formation, like rows of pyramids stretching 20-feet across. Once the tide washes over, they'll need the stability provided by dozens of 2-foot rebar pierced through the reef.
Using sledge hammers to pound down the rebar is taxing work as the metal slides back and forth in the mud, vanishing inch-by-inch. This final step in construction isn't the only tedious part of the project.
PenderWatch has been collecting and storing the recycled shells for six years and volunteer Jack Spruill says that just getting a permit took more than a year.
"Fifteen months ago, there was not a clear regulatory process for how this could be done under the letter and spirit of the law and regulations. And after a lot of consideration of the kind of reef we want to build, we had to get a CAMA major permit. It's the most intense permitting process one has to follow."
The state's Coastal Area Management Act, or CAMA, requires a Major Permit when any type of development, even stacking oyster shells, will involve environmentally fragile areas, like wetlands. Those applications are reviewed by 10 state and 4 federal agencies.
But Spruill and the other volunteers, who have already seen baby crabs and mud minnows settle into the reef, know the habitat they've created and the land they've saved, were worth the wait.
See Alan Cradick Photography's event photos.
Check out Michelle's blog post about the experience.
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