Merrimack officials say Anheuser‑Busch decline could remove roughly $1 million in annual wastewater revenue; new PFAS testing will raise costs

MERRIMACK — Town officials told the council on Jan. 14 they expect a significant revenue impact to the wastewater enterprise after Anheuser‑Busch reduced operations at its Merrimack facility.

Paul said the brewery historically contributed roughly $1,000,000 in annual revenue to the sewer enterprise. ‘‘They provide us with 1,000,000 dollars of revenue a year, roughly,’’ Paul told councilors, and managers said the town will use enterprise fund balance and seek new outside sludge and commercial customers to offset the shortfall while avoiding deep, immediate cuts.

Wastewater staff described new regulatory and operating costs that will add pressure. The plant’s new NPDS permit (effective April 1) requires more frequent PFAS monitoring — quoted at about $450 per PFAS sample and additional quarterly sampling — plus other laboratory work and an absorbable organic fluorine test. Staff also said they have added magnesium‑hydroxide dosing to stabilize pH since Anheuser‑Busch’s reduced flows removed an industrial buffering effect.

Officials noted large increases in Nashua‑charged pumping rates at the Penetruck Square station (cumulative increases of roughly 70% since 2022) that have substantially raised the town’s treatment costs for the flows Merrimack routes to that station. Town staff said building an independent interceptor/force main to avoid those charges would require multi‑mile infrastructure with a decades‑long payback and large up‑front cost.

Town officials reiterated that the wastewater fund is user‑fee supported (no general‑fund tax dollars), and that they will monitor revenue and, if needed, propose budget modifications later in the fiscal year rather than immediately raise sewer rates.