KIAWAH ISLAND — The way was cleared for homes on Capt. Sam’s Spit with a state Supreme Court decision Wednesday that an environmental advocate called a “drastic reversal.”

The 3-2 ruling ends a two-year court battle over the fate of the wildlife-rich, 150-acre spit that is a prized piece of disappearing natural coast. The justices upheld a lower court ruling that allows a sea wall and revetment to be built on the spit alongside Beachwalker Park.

The walls were sought by Kiawah Development Partners to build an access road across a neck of land from the current park parking lot to 20 acres of high ground where 50 homes are planned.

The ruling is a turnaround from a 4-1 Supreme Court decision in 2011 that overruled a lower court’s approval of a permit for the walls. The developers appealed that decision on different grounds.

“We’re thrilled, obviously,” said company spokesman Mike Touhill. He could not immediately say when construction of the walls might begin. The company “will continue sensitive and responsible development on all parts of Kiawah, not just on Capt. Sam’s Spit,” Touhill said.

Amy Armstrong of the S.C. Environmental Law Project was at a loss over what she called a “drastic reversal” by the court.

“I just don’t think there’s anything else we can do” in court to stop the walls permit, she said. But the project will continue battling individual construction permits, to do what it can to protect the spit. “Certainly this isn’t the end of the story,” she said.

The spit is a teardrop-shaped, continually eroding sand strip along Capt. Sam’s Inlet between Kiawah and Seabrook islands, left undeveloped while most of the rest of the island was built on.

It is one of the few undeveloped barrier island spits the public has ready access to because of adjacent Beachwalker Park.

Its cape beach is a feeding ground that draws seabirds. The inlet bank where the wall would be set is part of a rare strand-feeding ground, where dolphins feed on bait fish by driving schools onto the beach and jumping after them.

Touhill said the planned development would take place along only 20 high-ground acres, and that 85 percent of the spit is slated to be put under conservation easement.

Armstrong said the ruling is disturbing not just for the spit but for future court decisions in critical areas to be protected along the coast. The earlier Supreme Court ruling hinged on the need for permit decisions to consider cumulative impacts of a project on areas around it. The current ruling is “180 degrees different,” saying state regulators did not have what Chief Justice Jean Toal termed “expansive power” to deny a permit for a project outside a critical area, because of the area.

The first ruling gave environmental advocates strong grounds to fight other permits, she said. The new ruling seriously undercuts that.

“This is the one place we need to protect as public policy, to protect fragile natural resources along the coast. These unique places are being irretrievably lost to ill-planned development,” she said.

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