Boil water advisory in Gravenhurst is likely to last until later this week

Residents urged to boil their water for one minute before consumption

News release – District of Muskoka

A Boil Water Advisory (BWA) remains in effect for Town of Gravenhurst water customers until further notice. At this time, we advise that Gravenhurst water customers boil their water for at least 1 minute before consumption  (drinking, cooking, brushing teeth) or use an alternate potable source of water until the Boil Water Order and Advisory is lifted by the Medical Officer of Health at least midday on Tuesday, November 30, 2021.

What Happened?

Public safety is our top priority. The District continuously monitors all water treatment processes as required through the Safe Drinking Water Act.  The orders and steps taken on Saturday were done to protect our community out of an abundance of caution and ensure compliance with guidelines outlined by the Ministry of the Environment, Conservation and Parks (MECP) and Simcoe Muskoka District Public Health Unit (SMDHU). 

Early Saturday morning, November 27, 2021, District staff responded to a low fluoride monitoring alarm at the Gravenhurst Water Treatment Plant.  Immediate action was taken to confirm if all treatment processes were functioning as they should.  On inspection, staff resolved the cause of the alarm, but identified a fluoride container that was not properly labelled.  Out of an abundance of caution and to protect the health and wellbeing of our water customers, the District shut down the drinking water system to complete additional testing to ensure that no chemical contamination had occurred.  As a result, the Simcoe Muskoka District Health Unit (SMDHU) issued a “Do Not Use” order until further testing was completed. 

It was confirmed that chemical contamination did not occur, and SMDHU ended the “Do Not Use” order Saturday afternoon and then issued a Boil Water Advisory (BWA) order until bacterial testing is completed.  Bacterial testing is a standard procedure required after a water system is shut down. The required test results are expected by midday on Tuesday. 

We recognize how significant the impact of the BWA and understand our community counts on the District to deliver essential services, including clean, safe drinking water – we are working quickly to bring our systems back to normal. 

As part of our standard response to events of this nature, the District will be conducting a complete review of this water emergency.  More information will be provided as it becomes available.

How long will the Boil Water Advisory last?

At this time, we are required to sample water and submit consecutive tests for a minimum of 48 hour before a Boil Water Advisory can be lifted by the SMDHU.   We expect to restore service this week and ask Gravenhurst water customers to prepare to boil their water until at least midday on Tuesday, November 30, 2021.

We are working closely with the SMDHU and healthcare partners and can confirm we have had no reports of health issues related to this situation. Gravenhurst water customers who have consumed water before boiling should monitor their health and seek medical attention if required. 

Boil Water Advisory – Reminders

Owners and Operators of Food Premises in the Town of Gravenhurst on municipal drinking water system are reminded that while water pressure may be restored, it does not mean that the water is safe for use and shall not be used for food preparation.  Therefore, food premises that utilize water for food preparation are ordered to close, or are required to modify their business to only sell pre-packaged food items until which time the boil water order is lifted.

To prepare your water for residential use, bring water to a rolling boil for at least one minute.

Allow it to cool before:

  • drinking;
  • brushing teeth or rinsing dentures;
  • preparing food, wash fruits, vegetables, and other food;
  • preparing infant formula;
  • making ice, beverages, or other mixes; and
  • washing dishes: wash dishes with soap and water, rinse them and then sanitize them in a separate sink with a capful of bleach mixed with a sink full of clear water.

It is safe to shower or have a bath, but do not swallow any water – it is also safe to do laundry with the water. 

Hand hygiene is important for preventing the spread of germs and should continue during a Boil Water Advisory.

  • use an alcohol-based hand rub (60-90% alcohol) for hands that are not visibly soiled;
  • if hands are visibly soiled, clean them with a disposable wet wipe, then follow with an alcohol-based hand rub; or
  • if disposable hand wipes are not available, hands should be washed with water and soap, dried, and then followed with an alcohol-based hand rub.

For more information on safe drinking water during a Boil Water Advisory see or call Health Connection at 705-721-7520 or 1-877-721-7520 weekdays from 8:30 a.m. to 4:30 p.m.

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For emergency support, or if you require help or assistance accessing bottled water, please contact or 705-645-2412.

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