SCPA provides updates on DI's North Cell and saltwater mitigation bank

The South Carolina Ports Authority’s (SCPA) board of directors recently approved improvements to what is known as the “North Cell” dredge containment site on Daniel Island. The project will be carried out by S.J. Hamill for an approximate $2.54 million.

“Work on the Daniel Island North Cell Dredged Containment Area is expected to begin in late May or early June and will last approximately one year,” said SCPA Corporate Communications and Community Relations Manager Ern Dhand. “The work includes clearing the site of vegetation, reconstructing dewatering structures and raising the perimeter dike to achieve additional dredged material storage capacity.”

The project is designed to provide the appropriate amount of room for dredge material disposal for the SCPA.

The SCPA board also provided an update on the saltwater mitigation bank proposed for Daniel Island’s western edge along the Cooper River. The idea for the project was first announced to the public in 2017. A new round of sediment analysis was approved on April 17 to ensure that no contamination is present in the area.

“The purpose of the testing is to verify that the sediment on the site (previously used for dredged material) meets criteria for the Port’s plans to convert the 130+ acre area to wetlands habitat, which benefits the local ecosystem as well as supports economic development in the state,” Dhand clarified.

The project is currently in the permitting phase with the Army Corps of Engineers. If successful, the site would be one of the largest saltwater mitigation projects in South Carolina, at 134 acres. The land is part of a 1,300 acre tract owned by the SCPA on Daniel Island.

The term “mitigation” has been defined as the act of making a condition or consequence less severe – and that is exactly how the bank proposed for Daniel Island would be used. The bank will offset developer impacts to saltwater wetlands in other locations, explained Patrick Moore, the SCPA’s former environmental manager, in a 2017 article for The Daniel Island News.

“The idea is you need to build something – a road or a project – and you need to impact jurisdictional waters in the United States that are saltwater wetlands,” he said. “The Corps (of Engineers) makes this determination that it’s an unavoidable impact that is in the public interest. At that point you are allowed to fill it...but you have to offset that impact by improving or creating the same amount of wetlands or more somewhere else.”

Developers would be able to purchase credits from the saltwater mitigation bank, using a mitigation equation determined by the ACOE, in exchange for those impacts. The Daniel Island location would provide a much-needed resource, added Moore.

“There are no saltwater mitigation banks in the service area of Charleston Harbor,” he stated. “If you want to impact a saltwater wetland (now) you have to come up with your own plan from scratch to go and offset that impact. And that’s very difficult to do and very difficult to get approved.”

The salt water mitigation bank’s construction does not have a set date to begin. Dhand said that this will depend on the results of the soil testing.