Final test results from provincial laboratories have confirmed the safety of Sudbury’s municipal drinking water supply, Public Health Sudbury and Districts said, as officials continue to investigate what triggered earlier adverse readings

Following the lift of the boil water advisory on May 8, Public Health Sudbury and Districts confirmed the water supply is safe after receiving final lab results this morning, May 9.

In a press release issued at 9 a.m., the health unit stated that as part of the investigation, and out of an abundance of caution, water samples from Sudbury were sent to the provincial laboratories, with the results confirming the safety of the water, said PHSD.

The boil water advisory had been in place for approximately half of Greater Sudbury’s population since 6:22 p.m. on May 6 and was officially lifted at 6:59 p.m. Friday.

“We recognize this situation was difficult and disruptive for residents, businesses, schools, and community organizations. We would like to thank everyone for their cooperation and understanding,” Dr. Emily Groot said in a media release.

Groot is the associate medical officer of health for PHSD.

“While challenging, this situation also demonstrates that the routine monitoring and response systems worked as intended. Potential concerns were identified early, and a boil water advisory was issued to protect approximately 90,000 residents.”

The boil water advisory affected New Sudbury, Sudbury, Falconbridge and parts of Garson.

PHSD issued the boil water advisory as a precaution after routine drinking water monitoring detected coliform bacteria in samples, indicating that the drinking water supply may have been vulnerable to contamination, they noted.

“This early detection through ongoing surveillance is a key function of public health monitoring systems designed to identify potential risks before they result in illness.”

The underlying cause of the initial adverse water results have not yet been identified.

However, two consecutive sets of water samples returned Thursday and Friday showed no adverse results, which PHSD said indicates the water supply is now safe and that the water treatment and distribution systems are operating properly.

PHSD and the City of Greater Sudbury continue to review the circumstances that led to the advisory.

For more information, you can call PHSD Monday to Friday, 8:30 a.m. to 4:30 p.m. at (705)522-9200, ext. 464 (toll-free 1-866-522-9200) or visit phsd.ca.

At this time, there is no evidence of ongoing concerns in the drinking water system, PHSD said in their May 8 media release. Boil water advisories are issued whenever there is a potential risk to public health, even while investigations are ongoing.

This event reinforces the importance of sustained public health monitoring and response systems as a critical safeguard for safe drinking water and community health.

After a boil water advisory is lifted, residents should:


Run cold water faucets for five minutes or until the water runs clear.
Large-volume users (for example, schools) may need to run cold water taps longer on first use.
Run water softeners through a regeneration cycle.
Drain and refill hot water heaters set below 45°C.
Discard water filters that were used during the advisory and replace them with new filters, cartridges, and reverse osmosis membranes.
Discard the first three batches of ice produced in built-in refrigerator ice making machines.

In addition, food premises operators must:


Flush water lines: Turn on all faucets and water-using equipment (including hoses) and let them run for at least five minutes.
Clean equipment: Flush and sanitize all water-connected equipment including:
Ice machines. Empty the ice machine, and clean and sanitize the bin and all lines. Discard the first three batches of ice produced.
Beverage dispensers. Run soda fountains, coffee machines, and water dispensers with hot water for five minutes. Operators are encouraged to contact their suppliers for guidance.
Run empty machines through at least one full cycle to ensure sanitization before resuming normal use.
Clean and sanitize all food contact surfaces.