COLUMBIA During a visit last fall to a voter’s beach house, state Sen. Glenn Reese found himself watching in disbelief as ocean waves crashed at the edge of the seaside home.

So he figured his constituent, a Spartanburg jeweler who owns a house at Folly Beach, needed help. That prompted Reese to file a bill that would allow new seawalls to protect houses on eroding South Carolina beaches.

The trouble is, new seawalls have been illegal in South Carolina for 25 years – and Reese’s bill threatens to undermine a cornerstone of the 1988 coastal law. If Reese’s bill gets through the Legislature, a new wave of seawalls could be built on virtually every beach in the state, coastal regulators fear.

“We believe the bill, as written, would allow the proliferation of wood and rock sea walls on the active beach,” said Mark Plowden, a spokesman for the S.C. Department of Health and Environmental Control, which enforces the state seawall ban.

Seawalls make beach erosion worse when hit by waves. The crashing surf digs out the beach more rapidly as it pounds the hard walls, leaving less shoreline for the public to walk on.

With limited exceptions, South Carolina’s ban on new seawalls is one of the few parts of the 1988 beach law that has been strictly enforced through the years.

The rest of the law is peppered with loopholes that led to seaside development that never was envisioned. A state coastal study commission last week recommended changes to the law to make it stronger, not weaker

But Folly Beach has a problem, Reese said. The Charleston County beach is overdue for a federally funded shoreline renourishment project, Reese said.

In the meantime, the seashore is continuing to erode toward a number of houses, which in some cases have been washed under by the sea. That was particularly evident after Hurricane Sandy brushed past South Carolina on its way to blasting the Northeastern U.S., some residents say. Some of the houses at Folly Beach are worth $3 million, Reese said.

Reese’s constituent, Ed Yarborough, “is a victim in this, and all those other homeowners are victims,’’ Reese said.

Reese, D-Spartanburg, said he’s trying to help a constituent save his house, not wreck the state’s beach law.

DHEC says Yarborough was building a seawall in November in violation of the law.