Americans have long been advised not to drink the water when traveling to Mexico. But now some of our neighbors to the north—those living in Montreal—are under a boil advisory. City officials have advised residents to avoid using tap water for drinking, brushing teeth, washing food and even cooking without boiling it first. Likewise, some schools have been told to stop using drinking fountains.

What happened? According to officials, the city’s Atwater filtration plant, which supplies water to much of the south and east of Montreal, failed a recent test. The plant has been undergoing renovations during the past four years and, therefore, water levels in the reservoir have dipped. But on May 22 water fell to an unusually low level, allowing sediment to mix with the water. As a result, some residents noticed brown tap water.

Despite the water advisory, officials do not believe anyone will actually become ill from drinking the water.

“This is strictly a preventative measure at this point. We didn’t notice any bacterial contamination the water—strictly turbidity, just sediment,” Montreal fire department division chief Gordon Routley told CTV. “We think (illness) is unlikely but we can’t rule out the possibility.”

Residents, who have been advised to call 8-1-1 if they notice any health symptoms related to the water, are taking the advisory seriously. Hospitals have changed their water usage, schools and cafeterias have begun using bottled water, and local Starbucks have stopped selling coffee and tea – only serving pre-bottled beverages.

Areas of Montreal that get their water from sources other than the Atwater plans are not affected by the event.