If you want to continue to use your well water, bring it to a rolling boil for at least one minute and let it cool before using.
| Use tap water for: | Use bottled or boiled water for: | Do not use the water for: |
|---|
- Flushing toilets
- Washing clothes, linens and bedding
- Taking showers (for adults and older children)
- Washing floors
|
- Drinking
- Brushing teeth
- Making food and baby formula
- Sponge bathing babies and young children (after cooling the water)
- Making coffee
- Making ice
- Washing fruits and vegetables
|
- Kitchen and other household water filters
- Ice makers directly connected to the affected water supply
- Children's water play stations (e.g. wading pools and water tables)
|
How to disinfect a well
A residential private well owner can work on and disinfect his or her own well. However, there are some safety considerations when working on a well and many technical steps needed to properly clean and disinfect a well. Therefore, the well owner should consider retaining the services of a qualified professional or qualified technician.
You can disinfect your well contaminated with bacteria by "shock-treating" it with ordinary chlorinated household bleach containing 5.25 per cent sodium hypochlorite. In accordance with the Ministry of Conservation and Parks – “Well Disinfection of the Water Supply Wells - Requirements and Best Management Practices”, Ottawa Public Health recommends that the well water and equipment is chlorinated by dosing the well water to a concentration of at least 100 ppm of free chlorine. Don't use scented bleach for this purpose. Buy fresh bleach to do this because the chlorine in bleach is unstable and evaporates over time.
- Store enough clean water to meet household needs for a minimum of 12 hours.
- Bypass or disconnect any carbon filters, water softeners or other water treatment devices or else any pipes located past these filters will not be disinfected. Replace the filters once chlorination is completed. Highly chlorinated water can damage treatment units. It is important to follow the manufacturer’s recommendations to ensure treatment systems are properly disinfected. Be sure that the hot water tank’s heat source is shut off.
- Estimate the chlorine necessary to disinfect the water in the buildings plumbing including the hot water tank (calculator provided), and the chlorine necessary to disinfect the water in the well water column (calculator provided). Add them together.
- Drain all water out of plumbing including the hot water tank prior to dosing.
- Mix the chlorine required to disinfect the well in 25 litres (5 gallons) of water. Note: The well calculator accounts for the extra 25 litres of water used for mixing.
- Pour the mixture into your well.
- Thoroughly mix the chlorine solution and the water throughout the well column. This can be accomplished by attaching a hose to a tap and running water from the well through the hose and back into the well.
- Start the pump and bleed air from the pressure tank. Open all water taps one at a time, including outside hose bibs and cold and hot water taps. Allow the water to run until a chlorine smell is detected from each faucet then turn off each tap. Since chlorinated water can damage the action in a septic system, chlorinated water should not be allowed into the building’s sewage system.
- If a strong chlorine odour is not present, return to step 4, add half the amount of chlorine used for the initial treatment to the well and repeat steps 5 and 6.
- Let the chlorinated water stand in the system for 12 to 24 hours.
- Start the pump and run water through the outside hose away from vegetation until the strong smell of chlorine disappears. Make certain that the water does not enter any watercourse. Finally, open the indoor taps until the system is completely flushed. Taps or fixtures discharging to the septic tank systems should be temporarily diverted to an outside discharge point to avoid affecting the septic system.
- Wait 48 hours and then sample the water using the instructions and bottle provided by the laboratory. Two consecutive "safe" tests, performed on samples obtained over a period of one to three weeks, will probably indicate that the treatment has been effective.
- If the above steps do not alleviate the problem, it is recommended that the source of the ongoing contamination be determined and corrected, possibly with professional help.
Information obtained from Public Health Ontario
Resample your drinking water after corrective actions have been taken. As a private well owner, you are ultimately responsible for the system maintenance, operation and quality of your water. If your drinking water quality does not improve, you may need to have your well inspected by a licensed well contractor who will be able to provide you with options to address the issue.
You could also install a treatment system to remove bacteria. For treatment options, consult with a water treatment professional.
A well with a diameter of six inches (15 cm): Add five ounces (148 mL) of household bleach for every 25 ft (7.6 m) of water depth.
|
Well Depth (feet)
|
Well Depth (metres)
|
Bleach Volume (fluid oz.)
|
Bleach Volume (ml)
|
|---|
|
25
|
7.5
|
5
|
148
|
|
100
|
30 |
20 |
592 |
A well with a diameter of three feet (1 m): Add one quart (one litre) of household bleach for every five feet (1.5 m) of water depth.
|
Well Depth (feet)
|
Well Depth (metres)
|
Bleach Volume (litres)
|
|---|
|
5
|
1.5
|
1
|
|
10
|
3
|
2
|
A well with a diameter of two inches (5 cm): Add about one quarter ounce (6 ml) of household bleach for every 10 ft (3 m) of water depth.
Before starting the disinfection process, the outside of the sand point well (well point) and all associated equipment should be cleaned and disinfected. Homeowners can use disinfectant wipes or alcohol swabs. Unscented household bleach can be introduced in the well by removing the well cap. Ensure your pump does not run dry.
Using a drain plug opening, pressure gage opening outlet pipe, or other opening into the pressure tank, add chlorine bleach or other chlorine into the pressure tank, so that the water in the tank contains approximately 50 ppm free chlorine. This will take approximately 3 (three) tablespoons, or 1 ½ ounces of bleach for each 10 (ten) gallon of tank capacity (a 50-gallon tank, for example, will require approximately ¾ (three quarters) of a cup of bleach.
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