Wawa Council Discussion on THMs Turns Heated

Wawa Municipal Council's Corporate Planning and Policy Manual Committee meeting briefly turned heated during discussion of efforts to reduce THMs in the water.

Infrastructure Services Director Cory Stainthorpe was outlining efforts to treat THMs, noting that aeration or adding a coagulant were the two main possibilities: aeration did reduce THMs, but also reduced chlorine, which meant more chlorine doses and higher costs.

The focus turned to "flash-mixing" coagulants, with Stainthorpe stating the most effective seemed to be a poly-aluminum chloride - Councillor Bill Chiasson questioned the wisdom of using a chemical to treat THMs, retorting that staff should just "clean the damn well and get it done", and - when urged to calm by Mayor Ron Rody - questioned whether the mayor cares for "your people".

Stainthorpe replied that testing of the raw water from the lake near the intake and just before treatment showed the same amount of carbon, ruling out organics in the intake as a cause for the problem.

THMs are a by-product of organic material reacting with chlorine used to treat the water.

Appearing to become increasingly frustrated, Chiasson stated he didn't believe the readings - Mayor Rody cautioned him not to get personal, though Chiasson rose from his seat and went to the nearby door, stating "add chemicals, go ahead, kill your people" before leaving Council Chambers.

Discussion continued, with Rody stating that "if we don't add chemicals to our water, we'll never have clean water", and Stainthorpe assuring chemicals added would "attach" to the carbon and be removed by a filtration membrane - no decision was made, and the study is continuing.

Chiasson returned just after the discussion finished, and - at the end of the meeting - apologized to Stainthorpe for his outburst.

Algoma Public Health placed Wawa under an advisory in November 2014, due to THM levels exceeding Ontario Drinking Water Quality Standards: based on an average calculated from quarterly testing, THMs shouldn't exceed 100 micrograms per liter.

Stainthorpe says the average is now below that mark, but still high - highest in warm weather - and the advisory's remaining in place for now.

When issuing the advisory, the health unit emphasized there's only a risk from chronic, long-term exposure - drinking "a gallon a day every day for 35 years" - which would mean a "slight increase" to risk of bladder cancer.