Hampshire County, Massachusetts: drinking water report. Hampshire County in western Massachusetts has about 164,000 residents, including Northampton,…
Hampshire County in western Massachusetts has about 164,000 residents, including Northampton, Amherst, and the Five College area. Water comes from a mix of surface sources (Quabbin Reservoir supply, local reservoirs) and groundwater wells. The Connecticut River valley's agricultural activity and the region's legacy industrial sites create the water quality landscape.
The former Westover Air Reserve Base in neighboring Hampden County has a PFAS contamination plume that may affect southern Hampshire County groundwater. According to Massachusetts DEP's 2024 PFAS mapping, the plume from military AFFF use is migrating northward through the Connecticut River valley aquifer system. Three Hampshire County water systems have reported low-level PFAS detections during enhanced monitoring.
Agricultural activity in the Connecticut River floodplain contributes nitrate and pesticides to the alluvial aquifer. A 2024 USGS study of the Pioneer Valley found atrazine in 15% of sampled wells and nitrate above 5 mg/L in 12% – concentrations that reflect the valley's agricultural history and ongoing use.
Hampshire County's water quality is generally good compared to more industrialized regions, but emerging PFAS detections and agricultural contamination in the valley floor warrant attention for private well owners. The hilltowns west of the valley face different concerns – naturally occurring iron and manganese in bedrock wells.
Check your water for available data. For the range of concerns in Hampshire County, a quality carbon filter handles agricultural compounds and taste, while reverse osmosis adds PFAS protection. Our water filter guide covers both approaches. Pull your detailed report for local data, and visit our Massachusetts page for statewide data.
Drinking water is one exposure route. These federal datasets also cover Hampshire County, MA.
The EPA places Hampshire County, MA in Zone 2 - a moderate-risk category, with a predicted average indoor radon level between 2 and 4 pCi/L. Zone maps predict an area's radon potential from geology and existing indoor readings; they say nothing about a specific house. Testing is the only way to know your own level.
65% of homes in Hampshire County, MA were built before 1980, and 31% before 1950. Residential lead paint was banned in 1978, so housing age is the strongest available proxy for lead-paint exposure. This describes the county's housing stock, not any one home.
Modelled annual fine-particle pollution (PM2.5) in Hampshire County, MA averages 6.6 µg/m³, within the EPA's annual standard of 9 µg/m³. These are CDC modelled county estimates rather than readings from a specific monitor.
How radon zones work · Air quality by county · Lead exposure guide