LAKE WYLIE — Six years into waging a battle for Lake Wylie, the weed-eaters are taking it to the scourge.
Hydrilla, a non-native aquatic weed experts say can render water bodies useless for swimming, boating, and even as a drinking water source, isn’t nearly the problem now it was when former Lake Wylie Marine Commissioner Charles “Bo” Ibach deemed it the “scourge of the South.”
In 2007, Ibach called for hundreds, or even thousands, of weed-eating fish to combat the “menace.” The first load of 500 grass carp was released in May 2008. The weed was then observed at Dale’s Landing in Mecklenburg County, South Pointe Access, the Belmont water intake and just north of the I-85 bridge.
But then there also is the unseen. Tubers in the soil, which may lay dormant for a decade, can’t be seen. Duke Energy, which manages the lake, estimated then that 25 to 30 percent of the lake could be infested.
“When we started this it was 100 acres,” Commissioner Howard “Biff” Virkler said. “The carp have done an excellent job in controlling these things.”
At peak time during fall last year, only about 100 square yards of hydrilla were observed.
“It looks like the project is really working very well,” Virkler said of Lake Wylie’s hydrilla management plan.
Last month, the commissioners and Duke Energy partnered with the state to release 100 sterile Asian grass carp into Lake Wylie.
But, it isn’t permanent. While hydrilla can lay dormant during drought or fish feeding, the carp don’t last as long. Attrition takes about 25 percent annually. They can’t reproduce, prompting the annual re-stocking. Lisa Hoffman, Duke spokesperson, said the company is committed to managing hydrilla with “minimal impact to water users.”
“This effort to control hydrilla growth includes stocking sterile grass carp in Lake Wylie, as well as continuous monitoring of hydrilla growth throughout the growing season,” she said. “Sterile grass carp stocking is the most cost-effective, long-term method of hydrilla control.”
Hydrilla likely arrived through an aquarium dump, though it’s possible an angler looking to grow more cover or boaters brought it, experts say. Other lakes along the Catawba River have seen hydrilla issues, too. Since many boaters use multiple lakes, there’s always the possibility of new growth.
“Everyone can help prevent the spread of hydrilla by not introducing aquatic plants into the Catawba River and by removing all plant fragments from boats, trailers and bait tanks prior to leaving the lake so they are not transported to uninfested waters,” Hoffman said.