Skip to content

Treatment Scheduled for Black Fly Control on Potomac River

HAGERSTOWN, MD (August 19, 2019) – Washington County Government would like to notify all citizens that the Maryland Department of Agriculture, in partnership with the Department of Natural Resources, will treat targeted areas of the Potomac River in Washington County as an ongoing effort to control the black fly population. Treatment is scheduled for Tuesday, August 20, 2019 beginning at 8:30 a.m.

The department will apply a Bacillus thuringiensis israelensis (Bti)-based larvicide via helicopter (Bell 206 Long Ranger, green and white paint scheme. Tail number N641HA). Bti is a naturally occurring bacteria found in soils worldwide. It is a bacterial insecticide, not a chemical, and is only harmful to a very limited variety of organisms including midge, black fly, mosquito larvae and a few other aquatic Dipteran (flies) insects.

The treatment may cause temporary discoloration of the water, but it is completely non-toxic and is not harmful to humans, fish, crabs, or other aquatic invertebrates.

For additional information, please contact Washington County’s Public Relations and Marketing Department at 240-313-2380.

###

Other news:

Board of County Commissioners Appoint New Division Director of Environmental Management

Board of County Commissioners Appoint New Division Director of Environmental Management

WASHINGTON COUNTY, MD (September 16, 2026) – The Washington County Board of County Commissioners is pleased to announce the appointment of David…
TRAFFIC ALERT: Road Closure on Garretts Mill Road

TRAFFIC ALERT: Road Closure on Garretts Mill Road

KNOXVILLE, MD (September 15, 2026) – The Washington County Highway Department announces an upcoming closure on Garretts Mill Road between 19216 Garretts…
TRAFFIC ALERT: Road Closure on Lehman Mill Road

TRAFFIC ALERT: Road Closure on Lehman Mill Road

HAGERSTOWN, MD (September 14, 2026) – The Washington County Highway Department announces an upcoming road closure on Lehman Mill Road between Marsh Pike and…