How to Disinfect a Residential Water Well / Distribution System

Below, we’ve outlined the procedure for disinfecting residential water wells and distribution systems.

  1. Open the top of the well. Pour ONLY a quart (NO MORE) of regular household bleach.
  2. Run water from a hose connected to a main faucet/spigot furthest away from the well until water has a strong chlorine odor.
    • This process may take 60 minutes or more (perhaps 4 hours or even longer) depending on the depth of the well, the depth of the pump, and the length and size of distribution pipes and hoses. Periodic checking for chlorine in the water is required.
  3. Once chlorine is detected from the hose, turn off the water.
  4. Proceed to turn on each inside and outside faucet until chlorine is detected, then turn it off.
    • Be sure to run both the hot and cold water. This ensures the chlorine is contacting all surfaces within the plumbing system and well.
  5. Be sure to also run chlorine into the following lines:
    • Dishwashers
    • Ice machines
    • Refrigerator water taps
    • Toilets
    • Washing machines
  6. Allow the chlorine to stand in the pipes for 12 to 24 hours. In most cases, 12 to 16 hours (or overnight) is sufficient.
    • NOTE: It is not recommended to use/drink the water during this process.
  7. After the appropriate time period, flush main outside faucet until the chlorine smell is totally gone, then turn off faucet.
  8. Next, flush all inside faucets, dishwashers, toilets, washing machines, ice makers and refrigerator water taps until the chlorine smell is totally gone, and turn off each faucet.
  9. Run outside lines an additional 4 to 6 hours.
  10. After 48 hours of normal usage, the water is ready to resample. (Follow the “How to Collect a Well Water Sample for Testing” instructions above.)