The municipality of Casselman is reassuring its residents the drinking water is safe despite the dark colour and smell that could be present.
In an update Thursday evening, mayor Geneviève Lajoie said "water quality tests that are carried out twice a day by OCWA [Ontario Clean Water Agency] show that the manganese level is starting to drop."
Over the past week residents had raised concerns about the drinking water that is dark, appearing dirty or the colour of apple juice.
The discoloured water is because of high levels of manganese—a mineral distributed in air, water and soil—present in the South Nation River, according to the municipality.
The municipality advises residents to avoid boiling the water because that will only increase the concentration of manganese, it says.
Dr. Paul Roumeliotis, the chief medical officer of health for the Eastern Ontario Public Health Unit says the high levels are "temporary, related to hot and dry weather conditions affecting the properties of the source of the water." He says Ontario currently does not have a drinking water quality standard for manganese. "We have seen similar temporary, short-lived increases in the past in Casselman during hot dry weather."
"We will continue to advocate for a new source of drinking water for the city of Casselman. Manganese in water can cause discoloration but can still be used for bathing and washing," Roumeliotis said.
Residents react
Casselman residents say they don't enjoy seeing the water come out of the taps.
"I went and ran the bath to have a bath and it was poop brown," said Cheryl-Ann McConnell. "This has been the worst. They always claim it's the water that comes from the nation river and the high manganese in the summer, but they know this issue has been happening for so long."
And it's not just the look.
"It's funky. It's got a funky smell. And it's got a funky colour," said Stephenie Lamaina. "You know when you leave a water bottle in your car for a week, and it's the only water you got and you go, oh wait, this must be the old one. That's the taste. It tastes like old camping water.
"It’s gunking up these on-demand hot water heaters, which ours is now leaking. It's got precipitate all over the outside of the pipe and it seems to have busted the seam. Not enough to cause a flood but to cause of yucky drip. It’s in our dishwasher. Our toilets are brown."
Casselman mayor Geneviève Lajoie says the municipality is keeping on top of the data daily.
"So right now there's a trend that the manganese levels are decreasing daily. We haven't received the numbers this morning. But last night it did show that they did go down. And I expect that they'll continue to do that," Lajoie told CTV News Ottawa on Friday.
Health Canada guidelines
According to Health Canada, the maximum acceptable concentration (MAC) for total manganese in drinking water is 0.12 mg/L (120 µg/L). The aesthetic objective (AO)--that is, the amount that affects how the water looks, smells and tastes--for total manganese in drinking water is 0.02 mg/L (20 µg/L).
Canadians can be exposed to manganese through its presence in air, food, consumer products, soil and drinking water, with food being the main source of exposure, Health Canada says; however, manganese is more readily absorbed from drinking water than when it is ingested with food.
"Some studies in humans suggest an association between manganese in drinking water and neurological effects in children; however, they can only be used to support the choice of the key health effect. The effects observed in children are consistent with the neurological effects reported in the key animal studies used to establish the MAC," a 2019 Health Canada document says.
Health Canada says it is unlikely that exposure from drinking water through inhalation is likely negligible and absorption through the skin via showering or bathing is also unlikely to be significant, though Health Canada notes that few reports exist on dermal toxicity of manganese.
--With files from CTV News Ottawa's Dave Charbonneau.
