Got Algae?

Have you ever looked at your swim ladder or rip rap and thought, “that brown gunky stuff sure is ugly, how can I remove it or kill it?”

The stuff you see is green algae, turned brown by sediment in the lake water. While not attractive, it is not harmful to humans, pets or fish. Green algae are naturally occurring organisms in the lake and an important part of the food chain for our game fish. It accumulates on man-made structures because these don’t move around and are easy targets.

The best way to manage algae in your swimming area is by manually scrubbing it off with a stiff bristled brush/broom. It sinks when scrubbed off and is out of sight until it reaccumulates.

Use of even “pond safe” products are not recommended for use in the public waters of Smith Mountain Lake. It may be illegal to do so according to the State Water Control Law (§ 62.1-44.5.). SML is a public drinking water source and home to many species of game fish, invertebrates and other critters that could be harmed by discharge of chemicals or even “beneficial” bacteria.

Materials and chemicals used to control algae in small ponds are not safe for use in the lake. Dyes used to shade a pond and reduce the amount of sun that reaches algae, interrupts the food chain in a lake and causes deleterious effects to fish. If you swim where even “pond safe” treatments have been discharged, you may find your hair turns green or blue!

Copper based algaecides are toxic to fish and invertebrates when used at incorrect dosages. Before they can be used in any water body, a water chemistry analysis and a dosage calculation must be done. Excessive algaecide use can lead to a sudden drop in oxygen levels as the dead algae decomposes, potentially suffocating fish.

As a reminder, if you see something in the water that is unusual or concerning, SMLA has information on our website. The Virginia Department of Health provides even more information on their Swim Healthy pages.