An aerial black fly suppression operation has been scheduled for Wednesday and Thursday, September 2 and 3, 2015. Youghiogheny, Kiskiminetas, and Conemaugh Rivers along with Connoquenessing, Slippery Rock, Mahoning, Redbank, and Loyalhanna Creeks will be treated. This operation will begin at 0800, weather permitting, in Connellsville, Fayette County. Flights will be conducted in Fayette, Westmoreland, Armstrong, Indiana, Cambria, Clarion, Lawrence, Beaver, and Butler counties. The helicopter conducting the treatment will be a gray Bell 206 with red and blue stripes and N653HA tail number .

Helicopter Applicators, Inc. will be dispersing Vectobac 12AS, which is a Bti product manufactured by Valent Biosciences. Bti is short for Bacillus thuringiensis var. israelensis, which is a bacterial larvicide, not a chemical, and is the only product used in Pennsylvania's waterways for black fly suppression. Vectobac 12AS is a thick brown liquid resembling chocolate milk. The helicopter will fly low near tree top level and release the Vectobac 12AS at various predetermined positions on each stream.