Published On: 02.28.18 | 

By: Bob Blalock

Alabama Power team fighting sneaky invaders on Alabama lakes

Josh Yerby, Environmental Affairs Specialist for Alabama Power, inspects an aquatic plant on Lay Lake. Yerby is part of a six-member staff that fights invasive plants on the company's lakes. (Phil Free/Shorelines)

Josh Yerby eases the 18-foot Panther airboat off its trailer and into the still water of Lay Lake, readying to re-enact a scene from the opening credits of the long-ago TV series “Gentle Ben” – minus the full-grown bear. Those of a certain age will remember the show’s opening credits, which featured actor Dennis Weaver scudding across the Florida Everglades in an airboat.

“Unless you’ve done it, it’s something completely different on the water,” says Yerby, an Environmental Affairs specialist for Alabama Power. “You can go pretty much wherever you want to go.”

Yerby’s job requires him to go wherever he wants or needs on Alabama Power’s lakes. Yerby is one of a half-dozen employees who staff the company’s Aquatic Plant Management Program. He spends a good part of his time on the airboat, on Lay, Mitchell and Jordan lakes on the Coosa River.

Alabama Power takes on problem vegetation in Alabama lakes from Alabama NewsCenter on Vimeo.

On a brilliant fall day on Lay, Yerby offers a guided tour of aquatic plant infestations, starting with a dense, football field-sized mat of waterlettuce just a few hundred yards from the boat landing. The waterlettuce looks like just that – tightly bunched lettuce plants spreading across the water’s surface.

Yerby pilots the airboat across the waterlettuce, the airflow from the fan blades pushing the boat through the mass of plants. The airboat allows Yerby access he can’t get otherwise. Yerby can maneuver the airboat through vegetation so thick it would choke the motor of a regular boat. The airboat presents some challenges, though.

“This boat has no reverse. No brakes,” he says. “If you’re not giving it gas, you have no control over it.

“If those blades are spinning, it’s going forward. So you always have to plan ahead where you’re going,” Yerby says. “You can’t allow yourself to get into a tight situation where you can’t spin the boat around and get back out of.”

The airboat easily navigates the waterlettuce, an invasive species that is a perfect example of why Alabama Power has an Aquatic Plant Management Program.

“Waterlettuce is one of the world’s worst aquatic weeds and causes problems in virtually all waters it has invaded,” Lyn A. Gettys, of the University of Florida’s Fort Lauderdale Research and Education Center, writes in the handbook “Biology and Control of Aquatic Plants.”

“Waterlettuce spreads so quickly it can smother a body of water and interfere with boating, fishing, swimming and commercial activities,” Gettys writes. It also reduces water flow, breeds mosquitoes and can choke out native plants, which ruins habitats for animals and fish.

Waterlettuce is one of many plants Alabama Power’s program works to control. The Federal Energy Regulatory Commission (FERC), which licenses hydroelectric projects, requires the company to manage aquatic vegetation on its lakes. The FERC license for the Coosa River allows Alabama Power to use the Coosa’s water to generate electricity at its dams. In return, the company must manage aquatic vegetation with a plan that FERC has reviewed and approved.

That means leaving the plants alone, or even enhancing them, to improve fishing habitat, as well as the natural beauty and ecology of a lake – unless there is a need to control the vegetation. Yerby and the other Alabama Power specialists may take action against aquatic plants if they:

  • Provide a breeding habitat for mosquitoes, posing a potential public health hazard.
  • Threaten power generation equipment or water intake structures.
  • Limit recreational use of the lake.
  • Pose a threat to the lake’s natural ecology by choking out native plants.

“If any of those four criteria are met, we may initiate control measures,” Yerby says.

Alabama Power uses four measures to control aquatic plants:

  • Cultural control, which focuses on preventing invasive plants from being introduced into lakes and requires educating lake users about the threat.
  • Physical control, which includes hand-pulling the plants or lowering water levels to expose the plants to freezing and drying.
  • Biological control, which pits one organism against another to suppress growth. (Examples include using grass carp to control variable leaf milfoil, which Alabama Power has done on Thurlow Lake, and alligatorweed flea beetles to control alligatorweed on Neely Henry Lake.)
  • Chemical control, or spraying herbicides on plants to kill them.

Yerby says spraying herbicides blessed by the Environmental Protection Agency (EPA) is one of the most common control measures employed by Alabama Power and others that manage aquatic vegetation on lakes.

“These herbicides are EPA-approved for aquatic use, and many of them have been developed over the years to pinpoint a specific metabolic activity in these plants,” he says. “So they don’t harm any other organisms in the environment. These herbicides are really safe. In fact, some of the products we use on the lakes were designed to control algae in public drinking water systems. They’re very specific to the plant we’re trying to control.”

Environmental Affairs Specialist Josh Yerby has an enjoyable but important job protecting Alabama lakes from being choked by invasive vegetation. (Phil Free/Shorelines)

Company employees treat about 1,500 acres a year, which may sound like a lot, but that’s less than 1 percent of the 156,057 total acres of Alabama Power’s lakes.

Because the lakes are so large, the plant management program’s staff relies on the public for help.

“Public education is such a key part of what we do. We can’t be everywhere on our reservoirs, and we depend on lake users to let us know when they see something out of the ordinary,” Yerby says. “We would rather you contact us, even if it’s a false report, just to let us know that you see something, rather than not say anything and an exotic plant get out of control.”

Lake users can help prevent the spread of aquatic plants by cleaning their boats and trailers before transporting equipment. Possessing or distributing aquatic plants on the state and federal noxious weed list is illegal without a permit.

Alabama Power also responds to requests from the public – more than 800 in 2017 – to spray to control plant growth around docks, boathouses and shoreline.

For more information about Alabama Power’s Aquatic Plant Management Program or to report suspicious aquatic plants, visit https://apcshorelines.com/shoreline-management/.