I have been asked many times how to properly shock chlorinate a well and what effect it will have on the well and water quality.
Shock chlorination is only a temporary solution to water problems and may have to be done two to four times per month, depending on the amount of water in the well.
The easiest and safest method is too dump the proper amount of dry chlorine pellets into the well and let it dissolve in the well for about an hour.
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Put any water purification equipment you have into bypass mode, then run water from each tap in the house until you can smell the chlorine.
Close the taps and let the chlorinated water sit in the water lines for 12 hours.
After that, run the water from each tap until the water becomes clear or until the chlorine odour is gone.
Keep in mind that if you have iron in the water, the chlorine will oxidize it and you might have to run the taps for hours until the water becomes clear.
When that is complete, place your water purification system back into service and you are ready to use the water.
You may also use liquid chlorine for shock chlorination.
Proper amounts of liquid chlorine should be dissolved in about 100 gallons of water and poured into the well.
Then follow the same procedures for flushing the water lines.
Shock chlorination works well when you have an adequate water supply, such as about 1,000 gallons.
If you have bacteria in your water – E. coli or coliform – you should have a system that injects chlorine on a continuous basis.
The most effective method is to install the system in the house upstream of the pressure system.
Note that proper contact time is required for effective bacteria kill and proper oxidation of iron and manganese.
Once the system is shocked, I suggest installing a multi media filter to remove the excess chlorine as well as dead bacteria and oxidized iron.
The filter should be rebedded on average every three years.
In that time the microscopic pores in the media will become exhausted with dead bacteria and chlorine, and will have no absorption power.
If you have a specific water problem and would like advice, write to the Water Clinic, attention Philip Stadnyk, 850-47th St. E. Saskatoon, Sask., S7K 0X4, e-mail philip@thewaterclinic.com or phone 800-664-2561. Stadnyk is president of the Water Clinic and a member of the Canadian Water Quality Association. His views do not necessarily reflect those of The Western Producer.
