By Martine Wolfe-Miller, Communications Manager
MOUNT PLEASANT, S.C. (January 16, 2019) – At their January Meeting, Mayor Will Haynie and Town Council members received a report from Applied Technology & Management on the potential impacts of the Crab Bank restoration project on Shem Creek. That report is available online here.
“When informed by the U.S. Army Corps of Engineers that 825,000 cubic yards of added material would be dredged from the federal navigation channel in the Charleston Harbor and deposited on Crab Bank, we were both grateful and concerned,” said Mayor Haynie. “While Town Council and I strongly support the restoration of Crab Bank, we are concerned about the proposed location of the mitigation material that, we believe, would erode and migrate over time, further threating Shem Creek. We contracted with ATM to evaluate the Corps’ replenishment project in more depth.”
Mayor Haynie said he is optimistic about the outcome of the ATM report and wants to share it with the community. “The ATM report confirms that dredged material should be placed farther southeast to account for the islands’ northerly migration over the years,” he said. “We have forwarded the ATM report to the Corps and look forward to their review. Our goal is to work with the Corps to identify the plan that best preserves navigation within the Shem Creek Channel, while restoring, enhancing and maintaining Crab Bank as a major seabird and shorebird rookery.”
“Protecting Crab Bank is critical to the more than 5,000 seabirds, which nest on the island,” said Councilman Jim Owens. “Locating the dredge material in the appropriate location is paramount, as it will provide more high ground and a longer lifespan. It will help protect the Eastern Brown Pelican, the Royal Tern, Laughing Gull, Black Skimmer and American Oystercatcher from severe tidal over wash and human disturbance.”
Under the proposed Corps’ plan, the long-term movement of the sandy material shows significant sedimentation near the mouth of Shem Creek. The rate of northerly migration is projected to increase, making Hog Channel (between the island and Patriots Point) non-navigable within two years after the placement of the material. It could potentially increase the risk of attachment to the mainland, which would have a devastating environmental impact on the island’s rookery, by becoming accessible to predators.
ATM provided two alternatives to the Corps’ plan. Both place mitigation material farther southeast (away from Hog Channel) increasing the lifespan of the Corps’ project by up to 30 years, while reducing the risk of sedimentation in the Shem Creek Channel by 50 percent and therefore protecting the Mount Pleasant marsh shoreline.
Click on this link for more information about the Crab Bank Restoration Impacts Analysis on Shem Creek.