Dreaded aquatic plant returns to lakes

Those who live on the banks of Lakes Oliver, Goat Rock and Harding are seeing the annual return of a relatively new nemesis -- hydrilla.

The underwater weed grows like kudzu and can clog coves and inlets, making watercraft practically impossible to use. It's only been present locally for a few years, but it is already a major headache for the Georgia Power Company, which owns the three lakes.

Dawson Ingram, the lake resources manager for Georgia Power's Land Management Office, said he monitors the plant in all three lakes year-round, but more intensively during its summer growing season. He maps out where the weed is heaviest and directs a herbicide spraying program that holds the plant down. There is no eradicating it, Ingram said, only controlling it.

"It's a matter of management," Ingram said. "We're utilizing every option available to us by law."

Those are spraying herbicides into the water at infested sites, periodically drawing down the lakes to expose the weeds to air and trying to educate those who live on and those who use the lakes.

"It's a multi-pronged effort," Ingram said.

Chattahoochee RiverWarden Roger Martin said hydrilla has been in the United States since the 1960s, having been introduced from Asia when someone apparently dumped an aquarium with exotic plants in it into an open waterway in Florida.

It has since spread to pretty much everywhere in the United States, Martin said, but only recently to the upper Chattahoochee Valley.

"We've been blessed," Martin said. "(Lake) Eufaula's go it. (Lake) Seminole is eaten up with it. But we're been blessed so far."

Lake Eufaula (aka Lake Walter F. George) has been suffering from hydrilla infestation much longer than local lakes, Martin said.

The U.S. Army Corps of Engineers in 2007 decided to fight the infestation by introducing grass carp into the ecosystem.

Grass carp are voracious plant eaters, Ingram said, but they do not limit themselves to the hydrilla.

They also eat all the other underwater plants, destroying important cover that allows young fish to survive to maturity.

"Native vegetation is the big deals," Ingram said. "You can't train a carp just to eat hydrilla. Once they finish the hydrilla, they eat everything else."

Environmentalists at the time warned the Corps of Engineers against introducing the non-native species to the lake, but to no avail.

The Corps dumped 13,000 sterilized grass carp into the lake

"Auburn and (the University of) Georgia and everybody else told the Corps, 'Don't put grass carp in there. It's not the thing to do,'" Martin said.

"But they said, 'We're the Corps of Engineers, we'll do what we want to do.'

"It decimated the fishing."

About six weeks ago, the Corps put another 13,000 grass carp in Lake Eufaula again, Martin said.

"They say it's the most cost-effective way to do it, and they're going to do it," Martin said.

"Are we looking at two years down the road another fishing collapse? We don't know."

It is actually against Georgia and Alabama law to put grass carp into open waterways (unless you're the federal government).

Ingram and Martin say the best approach is for Georgia Power to hire licensed contractors to spray the masses of vegetation and for private homeowners to band together and hire licensed contractors to spray coves and inlets and around docks and boathouses, where the large rigs Georgia Power employs can't get.

They will have to get a permit from Georgia Power and must use one of the licensed contractors listed on their website at georgiapowerlakes.com, Ingram said.

Homeowners can also help by reducing the amount of fertilizer they use around the lake, Ingram said.

The excess fertilizer washes into the lakes and works just as well on hydrilla as it does on bermuda grass.

He also encourages homeowners to plant buffers between their lawns and the lake so that fertilizer runoff gets trapped before making it into the water.

It is very important for people using boats or other watercraft in infested lakes to clean their boats thoroughly after taking it out and before putting it into another lake, Martin said.

It doesn't take much of a sample to start a fresh infestation in another lake.

"It's the weed of all weeds," Martin said. "It's the kudzu of aquatic weeds."

This story was originally published July 5, 2015 at 10:31 PM with the headline "Dreaded aquatic plant returns to lakes."