Huron Perth Public Health has issued a boil water advisory for users of the Huron Sands Well in Ashfield-Colborne-Wawanosh.
The Medical Officer of Health said the advisory was issued Thursday after recent samples indicated unsatisfactory levels of bacterial contamination in the water supply.
The health unit warns that it is not safe for residents to consume water directly from the tap.
All water used for cooking or drinking must be brought to a rolling boil for at least one minute.
The advisory will remain in effect until two consecutive satisfactory water results are obtained.
