Researchers from NC State have developed a new stormwater filtration system designed to trap pollutants and bacteria that can often cause beach closures. The new system consists of a series of chambers that divert stormwater runoff into sand dunes, which act like giant filters. The filtering materials are buried beneath the dunes so that there are no visible materials on the surface. Researchers say that it allows beach sand to filter out bacteria that can be harmful to swimmers, and they are testing the filters along Kure Beach.
NC State biological and agricultural engineering professor Mike Burchell says national research shows the waters are already very clean. “This is really a pre-emptive move by the town and the NC DOT to protect people from the types of exposure to things that can be found in storm water when it's discharged to the ocean,” he says.
The below-ground filters take in as much as 97 percent of the runoff. Burchell says additional testing is planned for more developed coastal areas.