By Tiffany Williams –
WORCESTER, Mass. — City officials are advising residents to avoid swimming and fishing in a section of Lake Quinsigamond after an early morning sanitary sewer overflow on Friday discharged approximately 15,000 gallons of untreated wastewater, some of which entered the storm drainage system and flowed toward the lake.
The overflow occurred Friday morning in the vicinity of 23 Southwest Cutoff (Route 20), prompting an immediate response from city crews to stop the discharge and assess any potential environmental impacts.
According to the City of Worcester, the incident began at 5:20 a.m. on Friday, July 24, 2026, when a sanitary sewer overflow occurred from an underground pipe.
City crews responded immediately to the scene.
Officials said the leak was stopped at 7:23 a.m., bringing the overflow under control after just over two hours.
The city said the sewer system is now operating normally.
While crews were able to quickly stop the discharge, officials said some of the untreated wastewater entered the storm sewer system.
That storm drainage network ultimately empties into Lake Quinsigamond through O’Hara Brook near Whitla Drive and Ideal Road.
Because of that discharge, city officials are warning the public that bacteria levels could temporarily increase in the affected area.
The city specifically warned of the possibility of elevated E. coli levels at the point of the discharge and in the surrounding waters.
As a precaution, residents are being urged to avoid recreational activities in that portion of the lake until water quality testing confirms conditions have returned to safe levels.
Testing will be conducted every day until the results show bacteria levels have fallen back within acceptable standards.
Until then, restrictions remain in place for fishing and swimming in the affected section of Lake Quinsigamond.
Officials said individuals should use caution when on the lake until testing demonstrates that conditions once again support recreational use and those results are publicly announced.
Sanitary sewer overflows occur when untreated wastewater escapes from a sewer collection system before reaching a wastewater treatment facility.
Such overflows can result from a variety of factors, including blockages, equipment failures, damaged infrastructure or excessive flow within the sewer system.
When untreated wastewater reaches nearby waterways, public health concerns can arise because the water may contain bacteria and other contaminants capable of affecting recreational users.
E. coli is commonly monitored following wastewater discharges because elevated levels can indicate contamination that may pose health risks to people who come into contact with affected water.
Exposure to contaminated water can increase the risk of gastrointestinal illness and other infections, particularly for people who swim, wade or otherwise have direct contact with the water.
As a result, municipalities routinely conduct follow-up sampling after sanitary sewer overflows to determine when bacteria levels have returned to acceptable standards.
In Worcester’s case, officials said daily testing will continue until those standards are met.
The city has not announced how long the testing process is expected to take.
The duration will depend on the results of each round of water quality sampling.
Officials also have not reported any additional impacts beyond the affected area near O’Hara Brook and Lake Quinsigamond.
The city emphasized that the sewer overflow has been stopped and that the sanitary sewer system is operating normally following the incident.
Lake Quinsigamond is a heavily used recreational resource in Central Massachusetts, drawing boaters, anglers, paddlers and other outdoor enthusiasts throughout the summer months.
Because of its popularity, water quality monitoring following incidents such as sanitary sewer overflows plays an important role in protecting public health.
Residents planning to use the lake are encouraged to remain aware of updates from city officials regarding testing results and any changes to recreational restrictions.
Officials have not indicated when the advisory will be lifted.
The city said fishing and swimming in the affected section of the lake will remain restricted until testing confirms that bacteria levels have returned to acceptable levels for recreational use.
The City of Worcester released the following statement:
“On Friday July 24, 2026, at 5:20 a.m. the city experienced a sanitary sewer overflow in the vicinity of 23 Southwest Cutoff (Route 20).
Approximately 15,000 gallons of untreated wastewater was discharged to the street from an underground pipe. City crews immediately responded and stopped the leak at 7:23 a.m. The sewer system is operating normally.
Some of the flow made its way into the storm sewer system which ultimately drains to Lake Quinsigamond through O’Hara Brook, near Whitla Drive and Ideal Road. The public is advised of the possibility of elevated E. Coli levels at the point and around the area of the discharge. Testing will be done daily until levels return to an acceptable range. Fishing and swimming in this section of the lake is restricted until then. Individuals are advised to use the lake with caution until tested levels that support recreational use are attained and announced.”