Belknap County, New Hampshire: drinking water report. Belknap County sits in New Hampshire's Lakes Region, encompassing Laconia, Gilford, Belmont, and…
Belknap County sits in New Hampshire's Lakes Region, encompassing Laconia, Gilford, Belmont, and several smaller towns around Lake Winnipesaukee and Lake Winnisquam. Most residents rely on a mix of public water systems drawing from these lakes and surrounding aquifers, along with thousands of private wells serving rural properties. The county's water infrastructure ranges from modern treatment facilities serving lakeside communities to aging distribution systems in older mill towns.
New Hampshire lacks universal drinking water standards for PFAS despite widespread contamination across the state. The Merrimack River watershed, which drains portions of Belknap County, has documented PFAS presence from historical industrial activity and firefighting foam use at former military installations upstream. Lake-sourced systems typically face different challenges than groundwater-dependent towns. Surface water from Winnipesaukee and Winnisquam generally tests lower for PFAS but requires more aggressive treatment for sediment, organic matter, and seasonal algae blooms that can affect taste and odor.
Private wells throughout Belknap County face particular vulnerability. Granite bedrock that characterizes much of central New Hampshire can naturally leach radon, uranium, and arsenic into groundwater. The New Hampshire Department of Environmental Services has identified arsenic as a concern in private wells across the Lakes Region, with some areas showing concentrations above EPA's maximum contaminant level of 10 parts per billion. Well owners receive no mandatory testing requirements and often remain unaware of contamination until they test voluntarily. Historic land use, including old orchards treated with arsenic-based pesticides, compounds the problem in rural residential areas.
Lead remains a concern in Belknap County's older housing stock, particularly in Laconia's downtown neighborhoods built before 1986 when lead solder was banned in plumbing. The county's water systems generally maintain corrosion control treatment, but premise plumbing can still leach lead even when water leaves treatment plants safely. Schools and older buildings face elevated risk, and recent federal sampling requirements under the Lead and Copper Rule Revisions have revealed sporadic exceedances in similar New Hampshire communities. Seasonal homes around the lakes may experience higher lead levels when water sits stagnant in pipes during winter months.
Test your water, especially if you rely on a private well or live in pre-1986 housing. Certified laboratories can identify PFAS, arsenic, lead, and other contaminants that affect Lakes Region water supplies. Consider point-of-use filtration for drinking water even if you receive public supply, as treatment effectiveness varies between systems. Check your water for current data on your specific location, review our water filter guide for appropriate treatment options, and access your detailed report for full contaminant data. For broader context on New Hampshire's water quality challenges, visit our state page.