Analysis of drinking water from a well

Some substances can contaminate the drinking water in your private well. Their presence can be natural or the result of human activity. Surface wells are more susceptible to contamination by pollution than cased wells. However, water from a cased well is more likely to contain natural metals and minerals, which can contaminate groundwater.

As the owner of a well, you must ensure that the water is drinkable. The only way to ensure the quality of the water in your well is to have it tested regularly in a certified laboratory. You can get all the information you need on the website of the Ministère de l’Environnement et de la Lutte contre les changements climatiques (MELCC) : The Quality of Water in My Well .

Testing for microbiological parameters should be done at least twice a year, and testing for chemical contaminants should be done at least once during the period of your well usage. Depending on the results, further testing may be required. Before getting your water tested, contact your municipality to find out about any specific contamination problems in your area. Contaminants vary with the environment and soil type in the region or sector in which you live. The most common well-water contaminants are the following:

• Microorganisms
  • Escherichia coli (E. coli), fecal coliform and or enterococci
• Chemical substances:
  • Uranium
  • Barium
  • Arsenic
  • Nitrates and nitrites
  • Iron
  • Fluoride
  • Manganese

Useful websites

• Fiches synthèses sur l'eau potable et la santé humaine  (in French only)
  Institut national de santé publique du Québec
• The Quality of My Well Water  
  Ministère de l’Environnement et de la Lutte contre les changements climatiques