Winnipeg boil-water advisory likely prompted by sample contamination: report

Winnipeg's tap water was safe to drink even during a boil-water advisorythat was issued in January, an external report has found,but it could not pinpoint what caused the water test results that prompted the advisory in the first place.

The 1,000-pagereport, which has been submitted to the Manitoba's government's Office of Drinking Water for review, states that the city's water distribution system was not contaminated at the time the advisory was issued.

"The water was, and is, safe to drink," Geoffrey Patton, the city's acting director of water and waste, said in a news release Friday afternoon.

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From Jan. 27 to 29, about 700,000Winnipeggers had to boil or buytheir water after routine testing found coliform and E. coli at extremely low levels in six of 39 water samples.

At the time, businesses and residents were told that tap water was safe for bathing and laundry, but were advised to boil it for at least a minute before drinking it.

Subsequent tests all came back clean and there were no reports of anyone becoming ill from drinking or using tap water.

The report concludes that "it appears most likely that the source of the positive samples originated in either a sample collection or laboratory contamination event."

It confirms what city officials have suspected all along that the initial test results gave false positives, possibly as a result of a sampling or testing error.

However, it remains unclear if human error caused the positive test results. City staff admit it's a possibility.

"Unfortunately, yes, humans are involved. And sometimes error is going to happen," Tim Shanks, the city's manager of water services, told reporters.

"What we can do is find things to improve upon."

Patton said the city has made small changes to its water testing processes.

"There's changes in the sampling procedures, so we have independent audits that evaluated the sampling procedures sort of minor changes to documentation, some minor enhancements to the system," he said.