A small group of affluent landowners, who bought houses on an erosion-scarred stretch of beach, won a battle Thursday that could have reverberations across the coast for other oceanfront residents fighting rising sea levels that threaten their investments.

The politically appointed S.C. Department of Health and Environmental Control board agreed to let property owners at Debordieu Beach keep a wall of hard sandbags on the seashore, even though the department’s staff said the bags were put in illegally and were bad for the public beach.

The 3-2 decision followed a two-hour hearing in which lawyers for the property owners argued that leaving the bags buried under a pile of sand on the beach would be a worthwhile scientific experiment.