PA DEP will be conducting an black fly (biting gnat) larviciding operation along the French Creek on July 2, 2021,
beginning at approximately 12:00 PM. This activity will utilize a backback/boat/handheld method to apply
Vectobac 12AS (also known as B.t.i.) to the aforementioned waterway in Chester County.
PA. DEP personnel will be on site at all zones managing the operation.
Work on the French Creek will take place in
East Vincent Township, West Vincent Township, East Pikeland Township, and Phoenixville Borough
The B.t.i. 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.
This application of B.t.i. is not toxic to fish or other aquatic macroinvertebrates found in the treated waterways.
This work does NOT involve a spraying over the entire county.
This work is targeted to portions of specifically mentioned waterways.
The B.t.i. will be applied to designated areas every few miles along the treated waterways.
Any questions about the operation may be directed to contact below.
Product labels or SDS sheets can be provided upon request by PA DEP.
Department of Environmental Protection | Southeast Regional Office