CHARLESTON, S.C. (WCBD)- State and local conservation groups are raising concerns about proposed development in Berkeley County they say could leave thousands vulnerable to flooding.

The Southern Environmental Law Center (SELC) filed a lawsuit in federal district court on Wednesday on behalf of the Coastal Conservation League, Charleston Waterkeeper, and South Carolina Wildlife Federation, against the authorization of a development project on the Cainhoy peninsula.

The dispute centers around a 10,000-acre mixed-use development near the Francis Marion Nation Forest and Highway 41 that would add approximately 45,000 people to the Cainhoy area. Its development would involve the filling of at least 180 acres of wetland, a move which the SELC said would place around 45% of the planned housing in the floodplain.

“At a time when flooding is causing more, and more existential to the city, to put this much new development in such a vulnerable place is just going to make it harder for the city to maintain roads and services in the future,” said Chris DeScherer, Director of SELC’s South Carolina office.

In the lawsuit, the groups claim that the U.S. Army Corps of Engineers’ decision to authorize a permit is a violation of the Clean Water Act in that the CWA requires wetland fills be the “least environmentally damaging practicable alternative.

The SELC contends that during the permitting phase, the Corps was presented with plans that “fulfilled the project purpose by creating the same number of housing units while avoiding entirely or dramatically lessening wetlands impacts.”

“The Corps itself admits that smarter, safer development alternatives are feasible, so its decision to allow the Cainhoy development to move forward as planned defies common sense,” said DeScherer. “Approving a huge new development in such a vulnerable area is completely at odds with ongoing efforts to protect the City of Charleston from flooding and storm surge that happens on a routine basis now.”

In addition to flood-related issues, the lawsuit outlines potential threats to wildlife, including the endangered red-cockaded woodpecker which currently inhabits the Cainhoy site.

“Not only does the planned development put new residents in the direct path of flood waters, but it will also impact the nearby national forest and wildlife,” Sara Green, Executive Director of the South Carolina Wildlife Federation said. “The development will remove critical habitat for animals like the red-cockaded woodpecker on the Cainhoy site and negatively impact the national forest, an invaluable natural resource for all.”

The plaintiffs have asked the Court to enjoin the defendants, namely the Army Corps of Engineers, from dredging or filling wetlands until they comply with federal environmental laws.

News 2 has reached out to the U.S. Army Corps of Engineers for comment. They referred us to the Department of Justice, who declined to comment.