Septic tanks are silently spewing filth into a creek on James Island, where the $12 million set aside for sewer lines may not solve the problem. In Berkeley County, fetid water is rising to the surface, turning the yards of a gated housing development into swamps. Just north of Charleston in the town of Awendaw, hundreds of homes with septic tanks are planned near a coastal wildlife refuge, a move that environmental groups warn will threaten some of the cleanest waters on the South Carolina coast.

Up and down the East Coast, cities and towns are spending millions — or in the case of Miami, billions — to protect waterways endangered by inundated septic tanks. Monitoring wells in Beaufort County show South Carolina is no different, and that groundwater rises for weeks at a time to levels that would cause septic tanks to send bacteria into nearby streams, creeks and rivers.

A pair of Charleston lawmakers want to essentially ban new septic tanks in the coastal region, where rising seas and sinking land present a recipe for failure that threatens waterways along the coast.

Environmental groups are suing the state, arguing, in part, that it doesn’t give enough consideration to the unique forces near the coast that should require extra caution before allowing new septic tanks here.