Private Drinking Water

• wash hands before taking the sample
• remove screen, aerator or other attachments from tap. 
• run cold water for 2 to 3 minutes
• disinfect the faucet with a diluted bleach solution (1 part household unscented bleach to 10 parts water)
• run cold water for 2 – 3 minutes again. 
• do not touch the inside of the bottle or lid do not put the lid down or rinse out the bottle (the bottle contains sodium thiosulphate to neutralize chlorine, it may cause a reaction if ingested or inhaled).
• fill the sample bottle to the level marked on the bottle
• attach the name label found on the bag to the bottle. place the completed form in the bag provided, and wrap the bag around the bottle (fold the top of the bag over to keep the bottle in the bag).
• keep the blue card with a barcode sticker attached for your records and for calling in for results.

Water samples are sent to the London public health lab. If you have any questions about your sample submission please contact the lab.

To obtain your results:

 the toll-free interactive voice response (ivr) is available 24 hours a day, 7 days a week at:

1 (877) 723-3426
tty: 1 (866) 828-2238

Key in the barcode number from the sample bottle (pin) to hear an automated message with your test results and interpretation. Please wait 3-4 days for results to be available.

 If you indicated on the form that you will pick up the report at the lab, you will need photo identification and can only pick it up during business hours (see drop-off hours). If someone is picking up the report for you, they will need a potability of water release form and photo identification

 If you indicated on the form that you want the report mailed or made no choice, the report will be mailed to the name and address written on the form.

If you have any result other than 0 e. coli and less than 5 coliform your water is unsafe to drink! stop using your well water immediately.

See Public Health Ontario for what your results mean and what to do.

Contact a public health inspector for more information.

Consider using bottled water or a municipal supply if available. Boil your water if you don’t have an alternative source. (see temporary disinfection of drinking water below).

Coliforms. These bacteria are often found in animal waste and sewage, and soil and vegetation. If they are in your drinking water, it means surface water may be entering your well and your water may not be safe to drink.

Low levels of coliform bacteria (1 to 5) is considered safe in a private water supply, provided at least 3 samples have been taken over a six week period, the system is secure and is not subject to contamination (i.e. a dug or shore well).

E. coli (escherichia coli). These bacteria are normally found only in the digestive systems of people and animals. If they are in your drinking water, it usually means that animal or human waste is entering your well from a nearby source and your water is unsafe to drink without treatment.

If either of these organisms are found in your well water it could mean that you also have viruses or protozoa in your water. these are other tiny organisms that can cause human disease.

PHO laboratories test for the indicators of bacterial contamination (coliforms and e. coli). The sample is not tested for any other contaminants (i.e. nitrates). This means that even if your result shows there is no bacterial contamination in your drinking water, it still may be unsafe to drink. Well aware has information on how to obtain private drinking water testing. Click here for a list of licensed labs.

Please contact the Grey Bruce Health Unit for more information.

If you do not have an emergency supply of water or access to bottled water or a municipal water source, you can boil your water to kill pathogenic organisms (bacteria, viruses and protozoa). Bring water to a rolling boil for 1 minute, let it cool and store it in clean containers with lids. If the water tastes “flat” you can pour it from one clean container to another a few times to improve the taste. Use boiled water or an alternative safe source for washing fruits and vegetables, cleaning teeth, making ice, etc.

Your public health inspector may recommend that you disinfect your well. well disinfection can resolve some temporary problems and should always be done following construction of a new well or work on a well. Well disinfection is not a treatment system, if you have ongoing issues you should contact a well specialist and consider well rehabilitation. Well disinfection is an effective way of destroying bacteria, viruses and protozoa in the well and plumbing system.

See the procedure for disinfecting a well (public health Ontario) for disinfection instructions and a tool for calculating the amount of chlorine (unscented household bleach with no additives) required. If you do not know the volume of water in your well you may be able to find your well record from the moecc well record information system.

The information here is intended as a guide. If you are unsure about the process, contact a public health inspector at the Grey Bruce Health Unit or a licensed well driller who will be able to give you advice based on your well and/or carry out the process for you.

• Ensure your well is properly constructed and located to prevent the direct entry of surface water.
• Periodically inspect your well to ensure that there are no obvious problems (i.e. missing cap, evidence of flooding or ground movement). contamination of drilled wells usually occurs by surface water entering through the top of the well casing.
• Ensure that the area around the well is kept clear of debris, brush and any potential contaminants (chemical storage, pets, livestock, etc.)
• Ensure the ground surface slopes away from your well
• Do not use or store chemicals near your water supply
• Maintain your septic system to prevent groundwater contamination (see septicsmart! for more information)
• Properly abandon unused wells not being maintained for future use
• See source protection for more information

• Take 3-4 seasonal bacteriological water samples from your house or cottage.
• Take additional samples if you suspect a problem, the colour, taste or smell of your water has changed, or your well has been flooded.
• Always take a sample from a newly constructed or rehabilitated well, and anytime any work is done on the well or plumbing system
• If you have a treatment system and well, take a raw water sample at the same time you take treated water sample, the results can alert you to problems with your well.
• Assess your well for proper construction and monitor it.