Algae Toxins Taint Lake Needwood Waters in Rockville

If you’re visiting Lake Needwood in Rockville, do not touch the water, Montgomery Parks officials warned Wednesday.

High levels of an algae toxin known as microcystin have been detected at the 75-acre lake at Rock Creek Regional Park.

The toxin is produced by blue-green algae, or cyanobacteria. If ingested, microcystin can seriously harm the liver of humans and pets.

Dog owners are asked to keep their pets leashed and to keep them from drinking the water. People who fish are warned to only eat the properly cooked muscle meat of anything caught in the lake.

Wash your hands thoroughly if you come in contact with the water.

Warning signs were posted around the lake Wednesday.

“We will continue to monitor and update signs when the warning is lifted,” Jai Cole, principal natural resource specialist for Montgomery Parks, said in a news release.

Boating and fishing will remain open, park officials said, though portions of the lake could remain contaminated for the rest of the season.

Park officials issued a similar warning in October 2012. The Gazette reported a prior microcystin outbreak in 2010.

Swimming is not allowed at Lake Needwood.