FLEMINGTON, NJ – New Jersey wouldn’t pay for it. So Hunterdon County is picking up the tab for the Pennsylvania Department of Environmental Protection to spray the Hunterdon side of the Delaware River to suppress black flies.

“The Freeholders consider this program too important to our residents to sit idly by,” said Hunterdon Freeholder Deputy Director John Lanza today. “Black flies are not just annoying and intrusive, they have a negative impact on the quality of life for residents in communities along the river, as well as on tourism and other outdoor economic activities.”

Lanza is the Freeholder board’s liaison for Public Safety.

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“This program is a state responsibility because it normally covers Mercer, Hunterdon and Warren counties,” Lanza said. “The state has dropped the ball and as County officials we felt we needed to act to at least have the Hunterdon portion of the river sprayed, in order for our residents to gain some relief.”

Pennsylvania notified Hunterdon today that it would conduct an aerial black fly control operation along the Delaware River around 8 a.m. tomorrow, weather permitting.  

“The Black Fly Suppression Program will be treating the Commonwealth of Pennsylvania’s portion of the Delaware River,” the notice from Pennsylvania DEP said. “Without financial support from New Jersey, Pennsylvania can no longer manage and spray the New Jersey portion of the Delaware River; however, the entire river will be treated in Hunterdon.”

Freeholders here were disappointed to learn New Jersey “was not holding up its end for this important public health initiative, as it had done the previous two years,” Lanza said, but are “greatly appreciative” of Pennsylvania adding Hunterdon to its final spray operation of the season.

“They were very cooperative at adding us at the last minute,” he said. “Our County Vector Control Division Head Tadhgh Rainey is due significant credit for gaining the Pennsylvania DEP’s cooperation.”

Pennsylvania DEP announced in early July that black fly spraying would take place only along the Pennsylvania side of the Delaware River because of the lack of funding from New Jersey.

Hunterdon Freeholders contacted officials representing river towns requesting support for the funding and state Sens. Mike Doherty and Kip Bateman contacted the NJDEP to support the black fly suppression funding. 

But in a July 27 email, NJDEP told the Freeholders “We are unable to participate this year.”

Under the agreement, Hunterdon will pay $10,500 for Pennsylvania’s DEP to spray identified points along the Hunterdon side of the river.

According to the Pennsylvania DEP, the material used for spraying 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 material does not affect other aquatic life negatively.

The PADEP said this application of BTI is not toxic to fish or other aquatic macroinvertebrates found in the treated waterways.

The PADEP contracts with Helicopter Applicators, Inc. (HAI); Gettysburg, Pa., to provide the services.