Manchester Water Works staff told commissioners they are investigating shorter-than-expected filter run times at the Meramec River treatment plant and responding to increased PFAS and trichloroethene (TCE) detections near a new pump station.

John (title on record: watershed operations) and treatment staff said they are in a data-collection and discovery phase for the filter issues and have sought input from an alternate greensand filter manufacturer. They expect recommendations after additional testing and will convene with vendor representatives to evaluate corrective steps.

Separately, staff reported that the New Hampshire Department of Environmental Services (DES) recommended expanded sampling and additional monitoring wells after elevated PFAS and TCE were detected in one monitoring well near the new Rauler pump station. According to staff, DES indicated it could fund the recommended work to help identify the contamination source; if a responsible party is identified, that party would be expected to participate in cleanup costs.

Staff also briefed the board on infrastructure improvements elsewhere: the replacement of a high-service pump and new impellers (factory-tested to meet specifications), a vendor offer to assist with removal and installation at no additional cost, and a program to replace aging valve actuators with more robust units. The Lake Massapequa high-service station conversion to chlorine dioxide is paused pending HVAC work, which staff said they plan to bid once HVAC scope is finalized.

Commissioners discussed the likely budget impacts: staff warned that granular activated carbon (GAC) for PFAS treatment is expensive and could be a “game changer” for operating costs; the board said frequency of media replacement and lifecycle costs will determine future budget and rate implications. Staff said they will meet with hydrogeology consultants and DES to develop a response plan.