Fairfield County, Connecticut: drinking water report. Fairfield County occupies Connecticut's southwestern corner, home to about 950,000 residents in…
Fairfield County occupies Connecticut's southwestern corner, home to about 950,000 residents in communities from Stamford and Bridgeport to Danbury and Norwalk. Aquarion Water Company, a subsidiary of Eversource Energy, is the largest provider, serving much of the county from a network of reservoirs and well systems. The South Central Connecticut Regional Water Authority and smaller municipal systems serve other parts. Source water quality reflects the county's mix of suburban development, remaining forests, and industrial legacy.
Connecticut adopted PFAS action levels of 12 ppt for the sum of five PFAS compounds – placing it among the stricter states nationally. UCMR5 data shows PFAS detections in multiple Fairfield County water systems. The county's proximity to former military and industrial facilities along the Long Island Sound coast contributes to groundwater contamination in some areas.
According to the Connecticut Department of Public Health's 2024 monitoring data, three public water systems in Fairfield County exceeded state PFAS action levels and were required to implement treatment or source changes. Aquarion has invested in granular activated carbon treatment at several facilities to address these exceedances.
Fairfield County benefits from Connecticut's relatively strict PFAS approach, which pushes utilities to act on contamination that might go untreated in states with weaker standards.
Check your water for monitoring data specific to your provider. Even with utility-level treatment, a household filter adds protection. Our water filter guide covers effective options. Pull your detailed report, and visit our Connecticut page for statewide context.
Drinking water is one exposure route. These federal datasets also cover Fairfield County, CT.
The EPA places Fairfield County, CT in Zone 1 - the EPA's highest-risk category, where the predicted average indoor radon level is above 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.
Modelled annual fine-particle pollution (PM2.5) in Fairfield County, CT averages 7.1 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