Well Water Testing (Private Drinking Water)

We provide testing for the presence of the bacterial indicators of contamination, E. coli and total coliforms in private drinking water systems. This information is for people who rely on drinking water from a privately owned water source such as a well and other private drinking water systems (e.g., water from cisterns, treated lake water).

Unsure about who to contact?

Not sure who to contact with questions about drinking water quality?  Check out our know who to contact page to learn more…

Water Testing Information for Official Agencies

If you are a Public Health Inspector or official agency looking for information about water testing, please refer to our Public Health Inspector’s Guide – Water Testing.

 

About Well Water Testing

Your well water can affect the health of everyone who consumes it. At PHO, we test for the indicators of bacterial contamination:

  • Coliforms: These bacteria are often found in animal waste, sewage, as well as soil and vegetation. If they are in your drinking water, surface water may be entering your 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.

We do not test for other contaminants such as chemicals. This means that even if your results show there is no bacterial contamination in your drinking water, it still may be unsafe to drink.

For all other environmental testing, including testing for chemical contaminants, please consult with your local public health unit.

If you are an owner or operator of a large drinking water system under Ontario regulation 170/03 and need more information, contact the Ministry of Environment, Conservation and Parks. For more information about small drinking water systems regulated under Ontario regulation 319/08, contact your local public health unit.

Testing Your Well Water

Well water quality can change frequently. The best way to protect your drinking water is to test often.

How to Collect a Well Water Sample

It’s important to collect your sample properly. The accuracy of you test results depends on it.
  1. Get a well water sample collection kit. 
    Water collection kits are available from your nearest PHO laboratory, public health unit or designated pickup location in your area. Collection kits are not available at 661 University Avenue, Toronto.

  2. Use the sample bottle from the kit.
    We only accept drinking water collected directly into the bottle provided in the kit. Be sure to check the lid of the bottle. If the seal is broken, use a new collection kit. 

  3. Sample your well water when you are sure it can be delivered to the PHO laboratory in time. 
    We will not test a sample if it is too old by the time it is received by the laboratory. Contact your local public health unit for sample drop-off locations in your community. Confirm how soon a sample must be submitted after collection to ensure it is tested within the required 48 hour limit. 

  4. Remove any aerator, screen or other attachment from your kitchen faucet.
    If you cannot do this, take a sample from an inside tap with no aerator, such as the bathtub. Do not take a sample from an outside faucet or the garden hose.

  5. Turn on the cold water for two to three minutes. 
    This will help remove standing water from your plumbing system.

  6. Disinfect the end of the faucet spout with an alcohol swab or diluted bleach solution.
    Use a diluted bleach solution (1 part household bleach to 10 parts water) or an alcohol prep pad to remove debris or bacteria. Do not disinfect the spout with a flame because this can damage the faucet. 

  7. Turn on the cold water again. 
    Let the tap run for another two to three minutes.

  8. Remove the lid of the sample bottle.
    If the “tamper proof” ring on the lid is broken, use another PHO collection bottle.  Do not touch the inside of the lid, put down the lid or rinse out the bottle since it contains a preservative to neutralize any chlorine that may be in the sample.  

  9. Fill the bottle to the level that is marked.
    If the water level is below the fill line there may not be enough volume to perform the test.  If there is too much water, the sample cannot be mixed properly. Close the lid firmly and keep it cold but not frozen until it can be delivered to the drop off location.

Submitting Well Water Samples

Learn how to collect a well water sample and submit it to a PHO laboratory by watching this video from Grey Bruce Public Health Unit

Watch now

Ensure you sample meets all criteria to be accepted for testing: Acceptance Criteria Checklist for Private Citizen Water Testing.

By submitting the water sample for testing, the submitter represents and warrants that the water sample was taken from the Location of Water Source indicated in the test requisition and that the information provided is true in all material respects at the time of submission.  

The Ontario Agency for Health Protection and Promotion assumes no responsibility for the accuracy of the information provided, the manner in which the sample was collected or the mode by which it was transported to the laboratory.

Include (*mandatory):

  • Submitter’s  name* (first name is optional)
  • complete mailing address* (postal code is optional)
  • location of the water source address*, either:
    • “Water Source same as Submitter’s mailing address” tick box checked OR
    • Street number and street name or lot and concession, and Municipality / Township (include Emergency locator number/911#, County and postal code if possible)
  • date (year/month/day) and time of collection (indicate either AM or PM)*
  • public health unit number (see page 2 of the instructions)
  • tell us if your system has a purification system
  • daytime telephone number (include area code)
  • select how you would like to receive your test results: in person or by mail.

If your form is incomplete, the laboratory will not test your sample and you will need to submit another sample and form.

Image of the required fields of the water testing submission form

2. Write your name on the nametag that is on the plastic bag.

  • Peel the nametag off and stick it to the bottle.
  • Do not cover the barcodes. 
  • The name on the nametag must match the name on the form or the sample will not be tested.

 3. You can choose to get your report in person or by mail.  You can access your results by telephone through the Interactive Voice Response (IVR) at 1-877-723-3426.

  • To receive your results by telephone, remove one of the barcodes from the bottle and stick it to the "Water Results by Telephone” card in the kit. The number on the barcode is your Personal Identification Number (PIN), which is needed to get your results by telephone. This is the fastest way to get your results.

Image of the tag for labelling water samples

Follow these instructions to make sure your sample does not degrade before you submit it to the laboratory:

  1. Drop off the sample as soon as possible. Samples must be tested within 48 hours of collection.
    Contact your local public health unit for sample drop-off locations in your community. Confirm how soon a sample must be submitted after collection to ensure it is tested within the required 48 hour limit. Alternately, drop the sample directly off at the laboratory:

Drop-Off Hours

PHO’s regional laboratory locations
Monday to Friday, 8:30 a.m. to 4:30 p.m.
Closed Saturday, Sunday and statutory holidays* 

PHO laboratory - Toronto (For private citizen drinking water samples only)
81 Resources Road, Etobicoke, ON 
Monday to Friday, 8:30 a.m. to 1:30 p.m.
Closed Saturday, Sunday and statutory holidays*
Please note, PHO’s Toronto laboratory at 661 University Avenue is not accepting private drinking water samples dropped off in person.

* If the statutory holiday falls on a week day, samples will not be accepted the day before the holiday as well

  1. Keep the sample cool (not frozen) until you drop it off.
    Do not store the sample at room temperature or in a warm place as this can affect the accuracy of your results.
 

Get Your Test Results

You can usually get your test results two to four business days after you drop off your sample. 

There are several ways to get your report:

  • By telephone
    The toll-free Interactive Voice Response (IVR) is available 24 hours a day, seven days a week at 1-877-723-3426 Key in the barcode number from the sample bottle (PIN) to hear an automated message with your test results and interpretation
    • For TTY calls:
    1. Call 711 with your TTY device or follow the instructions provided by your telecommunications provider to call the Relay Service Operator.
    2. Ask the operator call 1-877-723-3426 and press 1 for English.
    3. Give them your barcode number and ask them to follow the prompts.
  • By mail
    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
  • In person
    If you indicated on the form that you will pick up the report at the PHO laboratory, show your photo identification at the reception desk during regular operating hours Monday to Friday 8:30 a.m. to 4:30 p.m. If someone is picking up the report on your behalf, they will need:


  • Report pick up is not available at 661 University Avenue, Toronto or 81 Resources Road, Etobicoke.

    The laboratory will hold the report for up to two weeks after the sample is received; it will be mailed after this date.

  • Electronic
    A written request must be submitted, including the timeframe of results you are looking for, sample barcode(s) if available and the location of the water source. Ensure you include: street address or lot and concession number, township/municipality, county and postal code.  Send your request by e-mail to customerservicecentre@oahpp.ca.

Understand Your Results

Read the Drinking Water Quality – Indicator Bacteria Fact Sheet

No significant evidence of bacterial contamination

Organism Colony Forming Units per 100 mL
Total coliform 5 or less
E. coli  0

What it means: No significant bacterial contamination was found.

What to do: Continue to test your drinking water on a regular basis to see if there are any changes in your drinking water quality.

Significant evidence of bacterial contamination

Organism Colony Forming Units per 100 mL
Total coliform More than 5
E. coli  0

What it means: Significant bacterial contamination was found.

What to do: Your drinking water may be unsafe to drink:

Consider using bottled water or a municipal supply if available.

UNSAFE TO DRINK: Evidence of fecal contamination

Organism Colony Forming Units per 100 mL
E. coli  1 or more

What it means: Indicates bacterial contamination from animal or human feces.

What to do: Your drinking water is unsafe to drink:

Consider using bottled water or a municipal supply if available.

NDOGN - No Data: Overgrown with Non-target.

What it means: Heavily contaminated with bacteria often found in the environment.

What to do: Your drinking water is unsafe to drink:

Consider using bottled water or a municipal supply if available.

NDOGT - No Data: Overgrown with Target

What it means: Heavily contaminated with bacteria often found in the environment and the indicators of bacterial contamination, total coliforms and / or E. coli are present.

What to do: Your drinking water is unsafe to drink:

Consider using bottled water or a municipal supply if available.

Private well owners are responsible for preventing surface water and other foreign materials from entering their systems. You can protect the long-term quality of your drinking water by protecting the water source and properly maintaining your well.

If you have had unacceptable test results in the past, take action to improve the long-term quality of your drinking water:

For more information on protecting your well and drinking water, contact your local public health unit or the Ministry of the Environment, Conservation and Parks.

Updated 30 Sep 2022