Independent New Hampshire Journalism · Northfield, NHCorrection and update, Sept. 19, 2026, 2:49 p.m. EDT: An earlier version of this article attributed direct quotes to Sen. Tim McGough and Reps. Nancy Murphy, William Boyd, Rosemarie Rung, Wendy Thomas and Jeanine Notter. Those quotes do not appear in the delegation’s Sept. 16, 2025 letter or in published coverage, and Granite State Report has not confirmed them. They have been removed and replaced with the letter’s own language and with remarks Rep. Rung gave the New Hampshire Union Leader. The article also misspelled the Naticook Brook aquifer. Since publication, the Merrimack Town Council authorized a low-salt agreement for Continental Boulevard, subject to review by the Governor and Executive Council, the Union Leader reported.
Merrimack Lawmakers Push State to Reduce Road Salt Use, Citing Drinking Water Threat
By Granite State Report
Concord, N.H. — September 19, 2025
The fight to protect Merrimack’s drinking water has reached a critical juncture — and local lawmakers say state bureaucracy is standing in the way.
On Sept. 16, 2025, Merrimack’s legislative delegation, state Sen. Tim McGough and seven state representatives, asked the New Hampshire Department of Transportation (DOT) to designate the state-controlled portions of Continental Boulevard and Industrial Drive as a “reduced-salt area.” The request came amid rising levels of sodium chloride in the Naticook Brook aquifer, which produces about half of the municipal water supplied by the Merrimack Village District (MVD), according to the letter.
“We’re concerned about the raised sodium chloride levels in the groundwater, particularly in the wells of the Merrimack Village District. It also is affecting private wells in the vicinity,” Rep. Rosemarie Rung (Hillsborough 12), a biochemist who cosigned the letter, told the New Hampshire Union Leader.
A Growing Contamination Problem
For years, the use of road salt in winter has been quietly seeping into Merrimack’s groundwater. According to local officials, chloride levels in two municipal wells have climbed so high that one well was forced to close, and a costly new one had to be drilled.
The contamination “hot spot” has been traced to the busy intersection of Industrial Drive and Continental Boulevard — both state-controlled roads. While Merrimack has already reduced salt use on locally managed roads, it cannot extend those measures to state roads without DOT approval.
According to the letter, MVD and the Town of Merrimack have already reduced salt on the town-controlled part of Continental Boulevard and on many other roads. The Town Council, the fire chief, the police chief, the public works director and MVD submitted letters supporting the reduced-salt designation at least a year before the delegation wrote to DOT.
Bureaucracy Versus Public Health
The delay, lawmakers argue, stems from a procedural requirement that all governing bodies in Merrimack must sign off before DOT will act. That includes the Merrimack School Board (MSD) — which has no direct authority over road maintenance.
While the School Board has expressed support for salt reduction on environmental and health grounds, members maintain their purview is education, not infrastructure.
“We agree and ask that the DOT remove the MSD requirement from this process and move forward expeditiously to approve the reduced-salt area designation,” the delegation wrote.
Broader Stakes
Chloride contamination is not unique to Merrimack. Across New England, decades of heavy salt use have polluted groundwater and damaged ecosystems. Unlike many pollutants, chloride does not naturally break down, meaning levels can build up over time and persist for generations.
Excess sodium in drinking water also poses risks for people with hypertension and heart conditions, while salt runoff degrades soils, kills roadside vegetation, and harms aquatic life.
“Salt doesn’t go away,” Rung told the Union Leader. “The only way to reduce salt levels in groundwater is to allow the dilution effect to occur by reducing salt application.”
Call for Change
In their September 16 letter to DOT Commissioner William J. Cass, Merrimack’s legislative delegation asked the agency to drop the School Board requirement and expedite approval of the reduced-salt designation.
The letter closes by thanking Cass for his help “in protecting the safety of drinking water in public and private wells served by the Naticook Brook aquifer.”
Cass answered on Nov. 6, 2025, asking the parties to obtain the Merrimack School Board’s approval, citing the department’s policy on such requests, the Union Leader reported. “This is not a light decision for the department as we consider the safety of the 15,000-plus vehicles that travel in this area daily,” Cass said.
The Road Ahead
The School Board deferred to the Town Council, and in January 2026 the Town Council authorized a low-salt agreement for Continental Boulevard, the Union Leader reported. Town Manager Paul Micali said the agreement needed review by Gov. Kelly Ayotte and the Executive Council at their Feb. 11, 2026 meeting before taking effect. Under a low-salt designation, crews would apply salt only at the beginning and end of storms, Micali said.
The Naticook Brook aquifer supplies about half of the Merrimack Village District’s municipal water.
Corrections: Granite State Report corrects verified errors promptly and appends a dated note identifying what changed and when. The corrections policy and the corrections register are public, and correction notes are never removed.
