Best Practices for Private Wells
Is your drinking water supply a private well or a private well system?
Private wells should be monitored regularly. Watch for changes in water taste, odour and colour. Have a sample of your well water tested through your local public health for indicator bacteria
Learn more in this fact sheet:
- Private Wells Fact Sheet (100 KB medium-sized PDF file)
Do you know if your well is being properly maintained?
Regardless of well type, nothing but water should enter your well, and it should only enter from underground.
The sides and top of your well should be watertight and free of leaks and seepage. No contaminants or foreign materials should ever have access to your well. Otherwise, the groundwater your well draws from and the water your family uses from the well could become contaminated.
It is always advisable to have a licensed well contractor do any work in or around your well.
- Make sure that a commercially manufactured well cap, cover, or sanitary seal is securely in place. The new covers prevent bugs and animals from entering.
- Inspect the cover or sanitary seal for cracks and holes.
- Inspect inside the well with a flashlight once every year. Early spring after snow melt is a good time.
- Look and listen for signs of surface water seeping or running freely into the well.
- Look for seepage through cracks or stains below joints on the inside of the well casing.
- Remove any debris floating in the well and prevent any more debris from entering.
- Have the well and plumbing disinfected with a chlorine solution by a licensed well technician after any work is done inside the well, or on pumping equipment.
- Check the condition of well vents. Look for flaws such as cracks or weakness in the vent tubing. Make sure that the fine-mesh screen is in place.
Private wells should be monitored regularly. Watch for changes in water taste, odour and colour. Have a sample of your well water tested through your local public health for indicator bacteria:
- At least three times per year, with one of those samples done in the spring.
- More frequently than three times per year if you know of problems.
- More frequently than three times per year if you have a highly vulnerable water supply, or if you are in a critical recharge area, which tends to be very sandy or full of gravel.
- After major plumbing or septic work. In addition, you should test for nitrates once every year, or more often if you have livestock or lands with high fertilizer application. Nitrate is a form of nitrogen that is stable in groundwater but levels greater than 10 mg per litre can lead to health problems, particularly in young children. Nitrate tests have an associated cost. Check the Yellow Pages for a registered laboratory.
Wells that are older and wells that have not been maintained properly are direct pathways to groundwater, or aquifers, and pose a direct risk to your drinking water supply. Improperly abandoned wells can also increase the risk of contamination entering nearby wells and provide a shortcut for contaminants to reach deeper aquifers. Unused wells also pose a physical hazard to people and animals on your property.
In Ontario, if a well is not being used or maintained for future use as a well, then the owner is legally required under the Wells Regulation of the Ontario Water Resources Act to plug and seal the well. In addition, a new well must be abandoned if it is dry or if construction is not completed. If using your well for drinking water, you must abandon your well if it:
- Produces mineralized water
- Produces water that is not potable
- Contains gas and you do not take steps to prevent a hazard
- Permits any movement of gas, contaminants, or other materials that may harm water sources and you do not take steps to correct the problem
- Is not constructed according to the Wells Regulation and you do not take steps to fix the problem or those steps have failed
There are many dangers to consider when working on abandoned wells and the equipment, materials and expertise needed to correctly abandon a well often exceed a well owner’s abilities. It is strongly recommended that you hire a licensed well contractor who uses licensed well technicians.
Sand Point Well Dug or Bored Well Drilled Well
The most common types of wells constructed in Ontario are the Sand point (Jetted), Dug or Bored, and Drilled. A properly constructed well is tightly sealed to prevent anything but groundwater from entering it. It’s critical to seal the well from surface runoff as a single gram of fecal matter can have up to 1 billion bacteria. (Diagram used with permission from: Well Wise: A comprehensive consumer’s guide for private water wells. Page 37)
Sometimes unused wells are not easy to identify. To determine if you have an unused well on your property, look for these clues:
- Pipe sticking out of the ground.
- Small building that may have been a former well house.
- Depressions in the ground.
- Presence of a concrete pit covered by lumber or metal.
- Presence of old windmills and windpumps.
- Additions to a home that may be constructed over a well to protect it from freezing.
If you suspect you have a problem with your well water or your well water test results shows unacceptable levels of bacteria, stop using the water and contact your local public health office. For more information, or to find out if your property is within a vulnerable area, contact your local Source Protection Region or Area.
You can find out which Source Protection Region or Area you live in at www.conservationontario.ca
For more information:
To receive information on water testing and to locate your local public health agency:
For more information on best practices for protecting your well:
It is important to properly maintain your well to ensure a clean and healthy supply of water for you and your family.
Outside your well
Know exactly where your well is located and keep potential contamination sources and activities away from your well.
- Take care when using any chemicals on your property, especially near your well. Never mix or use pesticides, fertilizers, herbicides, degreasers, fuels, and other pollutants near your well. Better still, consider alternatives to harmful or dangerous pesticides or fertilizers.
- Watch that lawn mowers and snow blowers are not leaking fuels near your well.
- Keep sources of E. coli bacteria away from your well. Animal and kitchen waste can contain E. coli bacteria. Do not allow liquids or wastes from contaminant sources such as garbage or manure piles to drain towards your well. These could lead to bacteria leaching into your water supply, especially during spring thaw.
- Keep other sources of bacteria away from your well. Do not bury brush piles, stumps, or other such debris near or uphill from your well.
- Do not use bark mulch or wood chips near your well. These organic materials are breeding grounds for insects such as earwigs, which can cause bacteria in your well if it is not properly sealed.
- Keep your septic system in good working order.
Mound up the ground around the well casing.
- The ground should slope away from your well. Make sure that your well’s casing extends at least 40 cm (16 in.) above the mounded earth.
- Keep a permanent grass buffer at least 3 metres (10 feet) around the well.
- Watch for ground settling or water pooling around the outside of the well casing.
- This could indicate that surface water could be accessing your well.
To learn more:
For more information on how to care for your private well contact your local Source Protection Region or Area:
Ausable Bayfield Maitland Valley Source Protection Region c/o Ausable Bayfield Source Protection Authority 71108 Morrison Line, RR 3, Exeter, ON N0M 1S5 519-235-2610 Toll-free 1-888-286-2610 www.sourcewaterinfo.on.ca
- Information relating to Regulation 903
- Information on well contractors is available on the Ontario Ministry of the Environment, Conservation and Parks website: Directory of Licensed Well Contractors in Ontario and/or contact the Water Well Help Desk: 1-888-396-WELL (9355) to locate a licensed well contractor
- Contact the Ontario Ministry of the Environment, Conservation and Parks (MECP) Public Information Centre at 1-800-565-4923
Conservation Ontario
120 Bayview Parkway Newmarket, ON L3Y 3W3 Tel.: 905-895-0716 Fax: 905-895-0751 info@conservationontario.ca
For more information on drinking water source protection, please visit the Ontario Ministry of the Environment, Conservation and Parks web page.
This project has received funding support from the Government of Ontario. Such support does not indicate endorsement of the contents of this material.
May 2023.
