If you notice a helicopter flying overhead Monday, county officials want you to know there’s no need for alarm. The chopper will be flying along the Delaware and Lehigh rivers in Northampton County as part of a preventive effort by the Pennsylvania Department of Environmental Protection (DEP) to control the black fly population in the area.
In a news release Friday, officials said will the spraying operation will begin at approximately 9 a.m. at Washington Crossing State Park in Bucks County.
“The Delaware River will be treated from Trenton to Portland, Pa., in Bucks and Northampton County,” it said. “The Lehigh River will be treated from the Delaware River in Northampton County upstream to the Lehigh Gap area in Lehigh County.”
The helicopter conducting the treatment will be a white Bell OH58 with blue and red stripes, officials said, and DEP personnel will be on-site at all landing zones to manage the operation.
The substance being sprayed in areas where the flies are known to hatch is called Vectobac 12AS and is manufactured by Valent Biosciences. “The…material is a naturally-occurring bacteria (Bacillus thuringiensis israelensis) that kills the immature (larval) form of the black fly when they feed on it in the waterways,” the release said. “It is a bacterial larvicide, not a chemical, and is the only product used in Pennsylvania’s waterways for black fly suppression.
“B.t.i. is not toxic to fish or other macroinvertebrates found in the treated waterways, and it degrades quickly in the environment,” it added.
Black flies are also known as biting gnats, and are considered a nuisance because of how they swarm people seeking outdoor recreation in the summertime, especially around rivers and streams.
The spraying operation by the DEP is conducted annually.
For more information on the operation, visit the state’s Black Fly suppression program website.