Authorities in Chateauguay say the boil water advisory that was put in place on Wednesday will continue until further notice.
The city released the results of tests today — it says one sample out of about 40 it tested over the last couple of days turned up traces of contaminants, and it says it's maintaining the boil water order as a precaution.
The order affects about 70,000 people in Chateauguay, as well as the neighboring communities of Mercier, Ste. Martine, Lery, St. Isidore and St. Urbain Premier.
Meanwhile, about 130,000 people in Brossard, St. Lambert, Greenfield Park and LeMoyne remains in effect. That order, which was put in place on Thursday afternoon, is unrelated to the problem in Chateauguay.
Affected residents are being advised to boil their water for at least one minute before consuming it. Authorities are recommending bottled water be used for things like food preparation and brushing teeth — though they say tap water can be used for things like washing clothes, bathing and showering.