Winnipeg making progress toward reducing incidents of brown water, engineers say

Winnipeg water-treatment engineers say they're making progress on plans to significantly reduce incidents of household brown water.

Late in 2017, the city started testing out the use of a new coagulant used to purify the city's drinking water within its treatment plant in the RM of Springfield, just east of the Red River Floodway.

Water-treatment engineers had already determined a coagulant called ferric chloride, used at the plant since 2009, led to a buildup of manganese in the city's water pipes, which in turn resulted in a flood of reports about brown water, especially during the summer of 2013.

While brown water due to manganese is not considered a health risk, the discoloration has made it difficult for residents to wash clothes and has sparked thousands of complaints to 311 since 2013.

• Chemical used in treatment made brown water worse, report says​
• Winnipeg hopes new water-treatment chemical will reduce brown water

To remedy the situation, the city began cleaning water mains to flush out manganese deposits and also planned to replace ferric chloride with a different coagulant, ferric sulfate.

Water services manager Tim Shanks said the dual moves have already resulted in reduced reports about brown water, though he had no statistics handy to cite.

"We're not where we want to be. We still get calls. We're still susceptible to discoloured water calls when there's a change in flow to the system," Shanks said Thursday at city hall, where he was supposed to make a presentation at a water and waste committee meeting that was cancelled when Elmwood-East Kildonan Coun. Jason Schreyer failed to show up.

Changes in the flow of water within the city's pipes stir up manganese and lead to reports about brown water.

"That issue is still there, so we're still vulnerable to events causing spikes in these calls," Shanks said.

'Should be immediate benefits'

Shanks said he hopes to see a significant reduction in those reports after his colleagues finish testing the use of ferric sulfate, to ensure it does not have any negative effects on water-treatment processes within the plant or on the water pipes below the city.​

"We do a lot of testing in the system," said Shanks, adding ferric sulfate is approved for use as a water-treatment chemical, just as ferric chloride was approved for use.

Certainly by the following summer, we should be able to see a statistical difference, a definitive improvement.- Water services manager Tim Shanks

The testing should be completed by October or November, he said. 

"There should be immediate benefits. We'd be putting less manganese in the system, so in a matter of weeks there should be a bit of improvement," he said

"Certainly by the following summer, we should be able to see a statistical difference, a definitive improvement."

Even with the new chemical, Winnipeggers will still experience some incidents of brown water, especially after major water main breaks, Shanks cautioned.

"The problem we're trying to solve here is this heightened sensitivity in the system to smaller flow changes — valve operations, hydrant use, that sort of thing — where it tints the water and the discoloration lasts longer than 20 minutes.That's the problem I'm confident we're eliminating," he said. 

"But if you have a major event right on your street, you are going to see discoloured water. That's just the nature of the system. We won't be eliminating that."

St. Vital Coun. Brian Mayes, who chairs council's water and waste committee, said he's receiving fewer complaints about brown water already.​