Hartford, Connecticut gets its drinking water from a system of reservoirs managed by the Metropolitan District Commission (MDC) — primarily the Barkhamsted and Nepaug reservoirs in the hills of northwestern Connecticut. The source water is excellent, consistently ranking among the cleanest municipal supplies in New England.
But clean source water doesn’t guarantee clean tap water. The journey from reservoir to faucet passes through miles of aging infrastructure, and Hartford’s industrial history has left contamination scars in the groundwater and soil throughout the region.
Lead: Hartford’s Hidden Problem
Connecticut has some of the oldest housing stock in the country. Hartford’s housing is particularly old — more than half the residential buildings in the city were constructed before 1950, during the peak era of lead plumbing. The MDC estimates thousands of lead service lines remain in the Hartford system.
Hartford’s 90th percentile lead levels have fluctuated around the EPA action level of 15 ppb over the years, sometimes crossing it. The MDC uses pH adjustment and corrosion control treatment to minimize lead leaching, but the age and condition of Hartford’s housing stock make this an ongoing challenge.
Connecticut requires lead testing in schools and has found elevated levels in drinking fountains and fixtures across Hartford Public Schools. The state has also expanded requirements for childhood lead testing, reflecting awareness that lead exposure remains a significant public health issue in older Connecticut cities.
Industrial Manufacturing Legacy
Hartford was once the Insurance Capital of the World, but before that, it was a manufacturing powerhouse. Colt firearms, Royal typewriters, and dozens of smaller manufacturers operated throughout the Hartford region. The aerospace industry — Pratt & Whitney’s jet engine plants in East Hartford — added to the industrial footprint.
These operations left behind contaminated sites. The Connecticut Department of Energy and Environmental Protection oversees cleanup at numerous brownfield and Superfund sites in the Hartford area. Volatile organic compounds (TCE, PCE), heavy metals, and petroleum compounds are common contaminants in the region’s groundwater.
For residents on the MDC system, the protected reservoir supply means industrial groundwater contamination doesn’t directly affect drinking water. But private well users in Hartford County suburbs should be aware of potential contamination from historic industrial operations.
PFAS Near Bradley International Airport
Bradley International Airport, located in Windsor Locks about 15 miles north of Hartford, is the region’s major airport. AFFF firefighting foam was used historically at the airport’s fire training areas, and PFAS contamination has been detected in groundwater near the facility.
The Connecticut DEEP and the airport authority have been conducting investigation and remediation. Some private wells in Windsor Locks and surrounding towns have been affected. Connecticut adopted drinking water action levels of 70 ppt for the sum of five PFAS compounds in 2021, and the federal EPA MCLs of 4 ppt each for PFOA and PFOS supersede where applicable.
The MDC’s reservoir-based supply provides separation from this groundwater contamination, but the issue highlights the broader PFAS challenge across Connecticut’s aquifers.
Combined Sewer Overflows
Hartford, like many older Northeastern cities, has a combined sewer system. During heavy rain, stormwater and sewage overwhelm the system and discharge into the Connecticut River and Park River. The MDC has invested over $2 billion in its Clean Water Project to reduce CSOs — building deep rock tunnels and expanding treatment capacity.
This doesn’t directly affect drinking water (Hartford doesn’t pull from the Connecticut River), but it affects the health of the region’s waterways and reflects the broader challenge of maintaining aging urban water infrastructure.
Water Quality and Treatment
The MDC treats its reservoir water with ozone for primary disinfection, which is more effective and produces fewer byproducts than chlorine alone. Chloramine is used for residual disinfection in the distribution system. The water is soft (low mineral content), which means it can be more corrosive to pipes — another reason corrosion control treatment is essential.
Fluoride is added per state requirements. The MDC’s Consumer Confidence Reports consistently show contaminant levels well below EPA limits for regulated compounds.
What Residents Can Do
- Test for lead. In Hartford’s old housing, lead is the top concern. Contact the MDC for testing or request an independent test.
- Run your taps. Flush cold water for 2-3 minutes after periods of non-use in older homes.
- Filter for peace of mind. A quality carbon filter handles chloramine, taste, and disinfection byproducts. For lead, get one certified to NSF/ANSI 53.
- Private well owners in Hartford County: Test for VOCs, PFAS, bacteria, and nitrates, especially near industrial or airport areas.
- Check for lead paint too. In Hartford’s older homes, lead exposure often comes from paint dust as well as water.
If you’re concerned about your water quality, a certified water treatment professional can test your water and recommend the right approach.
See also our coverage of Providence water quality and New Haven water quality.
Sources: Metropolitan District Commission, Connecticut DEEP, EPA SDWIS, Hartford County Health Department, USGS