State officials are hoping the buzz of helicopters will prevent the buzz of black flies around area waterways.

Within the week, the state Department of Environmental Protection will start aerial and backpack spraying to control black flies on about 1,700 miles of waterways in 35 counties, including Armstrong and Westmoreland.

Low-flying helicopters and ground crews using backpack sprayers from bridges and while wading in streams will be seen treating the following local waterways:

•Armstrong County: Allegheny and Kiski rivers and Mahoning and Redbank creeks.

•Westmoreland County: Conemaugh and Youghiogheny rivers and Loyalhanna Creek.

Black flies are prevalent during warmer weather and are a “pest that can inundate folks seeking outdoor recreation, especially around rivers and streams,” DEP Secretary Patrick McDonnell said.

The agency sprays black-fly suppressants for the outdoor enjoyment of residents, he said.

According to Purdue University, in parts of the upper Midwest and the Northeast, “black-fly biting can be so extreme, especially in late spring into early summer, it may disrupt or prevent outdoor activities such as hiking, fishing, and kayaking.”

DEP uses Bti, a naturally occurring bacterium, to treat the larval stage of four specific human-pest, black-fly species. This bacterium degrades quickly in the environment and does not harm the aquatic ecosystem, birds or other insects, according to DEP.

DEP notifies county and local emergency management officials prior to spraying .

Residents concerned at the sight of a helicopter or ground personnel are encouraged to call their county emergency management office to verify that a black-fly treatment is taking place in their area.

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