Several Connecticut communities have recently experienced water quality concerns, with the most notable being a localized E. coli detection in Essex that triggered a boil water advisory for multiple shoreline towns.

Boil Water Advisory and Lift

On July 10, 2026, the Connecticut Water Company detected E. coli bacteria during routine testing at a sample point in Essex. This prompted a mandatory boil water order for residents in Chester, Clinton, Deep River, Essex, Guilford, Madison, Old Saybrook, and Westbrook.

Officials advised boiling water for one minute before drinking, using it for food preparation, brushing teeth, or washing dishes. Infants, young children, the elderly, and immunocompromised individuals were warned of higher health risks.

Water tankers were deployed at local fire departments and public locations to serve affected residents.

The advisory was lifted on July 11, 2026, after repeat testing confirmed the water met state and federal safe drinking water guidelines and posed no E. coli risk. The company described the issue as isolated to one tap in Essex and not widespread.

Broader Water Quality Concerns

Beyond this incident, a 2025 study by the Environmental Working Group found that Connecticut’s 482 public water utilities serve 120 known contaminants, including haloacetic acids, bromodichloromethane, dichloroacetic acid, chloroform, and PFAS chemicals linked to cancer and other health issues.

The report highlighted that nearly all community water systems have detectable contaminants, and federal PFAS regulations are under political review, raising concerns about future protections.

How to Stay Informed

• Is It Clean provides real-time water quality data for Connecticut rivers and lakes, including E. coli levels and recreation safety tips www.isitclean.us.
• Local water utilities and the Connecticut Department of Public Health issue alerts for boil water notices or other service disruptions.
• Residents can use ZIP-code search tools to see contaminants in their specific water system.
• Bottom line: The most recent major event was a short-lived boil water order in July 2026 due to a localized E. coli detection, but broader concerns remain about chemical contaminants in Connecticut’s tap water.