I am often asked about the correct procedure to disinfect your well. You would do this process to get rid of choliform or ecoli bacteria from your water. This is a very simple process and most home owners can easily do it themselves.
You will need a package of chlorine test strips, a bucket, rubber gloves and one 4 litre jug of unscented household bleach. This is usually enough but see chart at bottom to calculate the correct amount for your well.
1) Before you start you will need to make sure you bypass any water softener, iron filter or any other type of back washable filter and remove any filter cartridges from an Ultraviolet Disinfection system as the chlorine will damage these items. Be sure to run water through your UV system (if you have one) and that it remains on at all times during and after this procedure.
2) Remove the well cap. You can easily remove the bolts to get access to the well head to put the chlorine in.
3) Mix the bleach with about 3 gallons of water to dilute it as straight bleach could cause corrosion and harm the well casing. Be careful not to spill this solution on yourself, your clothing or even the lawn.
4) Carefully pour down into the well.
5) Connect a hose to an outside hose bib and run the water back into the well head for about one minute to thoroughly mix the chlorine with your water.
6) Inside the house, turn on one cold water tap and let it run until you can smell chlorine, use the chlorine test strips to confirm. Shut the tap off.
7) Repeat step 6 at every cold water tap in the house, one by one, including the bathtub(s) and shower(s), washing machine and toilet(s) - one flush is enough. Don’t forget the outside taps as well.
8) Go back to the well and repeat step 3 (add the same amount of unscented bleach into the well again).
9) Return to the house and this time run all the hot water taps, one by one, and turn off again.
10) Return to the well but this time add ½ of the required amount of unscented bleach.
11) Using a garden hose, attached to an outside tap, wash down the inside of the well casing with the chlorinated water. Caution: some hoses may not be suitable to drink from as they may contain contaminants such as lead.
12)_ Let the system (well and plumbing) sit overnight to allow the bleach to work
13) After the contact time, run the water out to a driveway, as this water has high levels of chlorine, until you no longer smell chlorine. Do one load of clothes in the washing machine without clothing to make sure the high levels of chlorine in the water are gone and does not damage your clothes.
14) Put water softener, iron filters etc back into service and replace any other filters removed for this procedure.
15) Test you water 7-10 after this procedure to see if the bacteria is gone. If the bacteria is not gone contact a water treatment professional about an on going, continuous disinfection system like an Ultraviolet Light.