folly erosion (copy)

Hurricane Matthew caused significant erosion on Folly Beach in 2016.

The shapes of islands in the Charleston area change constantly, guided by slow and steady forces like wind and water or by major storms and hurricanes. But few islands are changing as quickly or as dramatically as Folly.

So it makes sense that the Folly Beach City Council last week passed a six-month moratorium on building within 20 feet of the so-called “critical line” for waterfront properties. That means no new construction permitted too close to dunes or marshland.

The moratorium isn’t meant to stop development so much as it is to let city officials iron out acceptable construction policy for waterfront areas subject to erosion. And that’s a complicated issue.

A new state law, for example, says homes can’t be built past the dunes, but doesn’t spell out exactly what a dune is. And Folly Beach might be exempt from those requirements altogether. The state Department of Health and Environmental Control also regulates beachfront development.

The tangle of regulations aside, how close is too close to the water? On parts of Folly Beach, that question is troublingly close to irrelevant. Erosion has left some homes so close to the water that a high tide laps at the stilts on which they stand.

Folly’s erosion is caused mostly by rock jetties that protect the shipping channel into Charleston Harbor. The jetties block sand flowing toward the island that would otherwise build up on Folly, meaning that currents carry sand away but don’t supply more of it. And storms like Hurricane Matthew and Tropical Storm Irma over the past few years have made the problem worse.

Folly Beach has spent about $85 million in combined local and federal funds over the past two decades to renourish beaches that keep washing away.

In other words, the setback for building a beachfront home must take into account the fact that the beach is never really going to get any bigger, even with a steady renourishment program. The city cannot afford to subsidize unwise development too close to the water.

Mandatory setbacks should allow plenty of space for future erosion.

Similarly the new state law ought to be interpreted in such a way that prioritizes beach preservation over the ability to build homes close to the water. After all, the concern is not just for environmental health but for safety and cost effectiveness too.

Beachfront homeowners worry that they might not be able to rebuild or remodel properties caught on the wrong side of new state-designated lines. That’s a fair concern, but it doesn’t make much sense to continue investing in something that’s likely to wash away. And state law allows appeals in most cases.

But on few South Carolina beaches is the situation so critical as on Folly. The beach is perpetually washing away. It’s better to build safely than be sorry.