Treatment to fight hydrilla in Lake Waccamaw set to start

LAKE WACCAMAW, NC (WWAY) — Treatment will start next month to fight what the state calls a significant hydrilla infestation at Lake Waccamaw State Park, according to the NC Division of Parks and Recreation.

The agency says a contractor will begin the first of three planned applications this year of the chemical fluridone in an effort to control the fast-growing, invasive aquatic plant, which threatens to curtail recreational use of the 8,938-acre lake. Treatment will be concentrated in the northwest area of the lake near a public boat ramp.

The total cost for the treatment is $196,660. The NC Division of Water Resources’ Aquatic Weed Program is paying for half the cost with a match coming in equal amounts from the town of Lake Waccamaw and Columbus County.

The application poses no danger to swimmers, boaters or others in contact with the lake’s waters.

Researchers with North Carolina State University and the state parks system recorded the hydrilla outbreak in 2011. Response is being coordinated by a Lake Waccamaw Technical Advisory Committee, with representatives from seven state and federal agencies as well as other stakeholders. The committee considered a range of treatment options, such as the introduction of grass carp, but determined that chemical application was the most appropriate considering the lake’s rare, endemic species.

Hydrilla is a submersed aquatic plant that can create nearly impenetrable mats of stems and leaves on a lake’s surface. An invasive species from central Africa, hydrilla impedes recreational use of waterways, crowds out native vegetation and can ultimately harm fish and other aquatic species. Its spread is often attributed to boats that are trailered from lake to lake.

More than 600 acres of the lake is infested with hydrilla. Researchers predict that if the hydrilla is left untreated, the infestation could spread to about 1,500 acres within a year and about 5,700 acres within three years. This is the first recorded hydrilla infestation of a Carolina bay lake. Lake Waccamaw is the largest of the natural bay lakes in southeastern North Carolina and home to a number of rare species of fish and mollusks. The lake holds the status of National Natural Landmark.