FOLLY BEACH — When ocean waters invade, residents here now can defend themselves legally — with a wall.

The S.C. Department of Health and Environmental Control overruled its coastal regulation staff last week, allowing Folly Beach homeowners Stacey and Bert Weiss to build walls to protect their property, now virtually swamped by high storm tides.

“It’s a good ruling for us and good for others on Folly who are trying to take care of their homes,” Stacey Weiss said.

Not everyone agrees.

“It’s a huge move in the wrong direction. We need to retreat more from the beachfront to preserve any chance of beach conservation,” said Nancy Smith, a Folly Beach homeowner who doesn’t live on the beach. “It flies in the face of the State Beach Management Act. Folly’s exemption from certain regulations should not be exploited to protect private property.”

The ruling is limited to Folly Beach because of that exemption in state law governing beach development. Folly already has one of the largest assortment along the coast of homes with rock sea walls. This ruling could allow more to be built, and sea walls exacerbate beach erosion.

“Any time you’re saying DHEC doesn’t have jurisdiction in a place that’s influenced by the tides, that’s problematic,” said Amy Armstrong, of the S.C. Environmental Law Project.

Meanwhile, the reversal of the DHEC staff permit denial could have the twin effect of encouraging more people to appeal denials at other beaches and of further restricting staff.

“Yes, there might be some permits issued for things that you wouldn’t expect permits to be issued for,” said Linda Tucker, Isle of Palms city administrator, although she said it was unlikely because of the Folly exemption.

The Weisses were among about a dozen property owners who defied regulators last spring; they built barriers to protect their homes from storm tides sweeping under them, barriers the state said weren’t allowed.

The DHEC board ruled that the homeowners were right — the state didn’t have jurisdiction because of the exemption.

What’s at issue is a line in the sand, or two of them. The state has jurisdiction seaward of a base line that is decided by distance from the mean, or average, high tide line. Folly is exempt because its beach is more severely eroded due to the Charleston shipping channel jetties.

The Folly line is determined by the remnants of an old sea wall that ran the length of the island. Behind that line, the city has jurisdiction.

After earlier rounds of renourishment, homes were built right up against that line; the city lost a lawsuit trying to stop it.

With the recent federal-funding delay for renourishing the beach, tides came past the old wall and began tearing at those homes. Regulators argued that they had jurisdiction because the area was now the active beach. The board said that was wrong.

“The line is a fixed line. It’s not a moving line,” said Mary Shahid, the Weisses’ attorney.

About 30 properties along the beach are immediately affected by the ruling; fewer than a dozen do not have sea walls yet, Shahid said.

“I think it’s a limited impact,” she said. She already has heard from other owners wanting walls.

That’s now for the city to decide, and Folly Beach has freely granted permits during the latest rounds of erosion.

“We don’t want to do anything that would ruin the environment for anybody,” said Mayor Tim Goodwin. But “whether they should have been built or not in the first place, these homeowners have the same rights as everyone else.”

Katie Zimmerman, Coastal Conservation League project manager, called sea walls a band-aid solution.

“What has been going out at Folly for the past few decades, we have houses built out where they should not have been built,” she said. The ruling “doesn’t mean this is a free-for-all for Folly. They still need to make smart decisions.”

Zimmerman called the jetties the bigger issue. She said a study to find ways to stop the erosion caused by the jetties blocking the flow of sand to the beach is overdue.

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