Disinfecting Your Water System

From time to time it may become necessary to disinfect your well and water piping.  Disinfecting is fairly simple if you follow these steps:


1. Measure the depth of the water column in the well.  Turn off the well pump.  Take a string at
least 10 feet longer than the depth of your well.  Tie a clean stainless steel weight to the string.   Never use lead or brass!  Lower the string until the weight hits the top of the water. Mark the point on the string where the string meets the top of the casing.   Then lower the weight until it hits the bottom of the well.  Mark that point where the string meets the top of the casing.  Measure the distance between the two marks to get the height of the water column. 

2. In a 5 gallon bucket pour chlorine bleach (laundry bleach) into about 3 gallons of water.  The amount of bleach is based on the depth of the water column.  Use 1 quart (32 oz.) of bleach for water columns of 100 feet or less.  Use an additional pint (16 oz.) for every 50 feet in excess of the first 100.  (Do NOT use bleach with additives such as "fresh scent" or "lemony scented.") Stir to mix.  When mixed well, pour the water/bleach
mixture down the well.  Note:  It is better to use more bleach than not enough.

3. Go into house turn on the well pump and, starting with the highest faucet, showerhead, etc. turn
on the water until you can smell chlorine.  When you smell chlorine turn off the faucet.  Proceed doing the same throughout the house.  Don't forget the toilets laundry, dishwasher, and outside taps.

4. Wait at least 4 hours.  Overnight is even better.

5. To protect the sewage system, start with the outside tap.  Run the water until the chlorine smell disappears from the tap.  This may take 15 minutes or more.  When you are sure that the outside tap water is free of chlorine, turn off the tap and repeat throughout the house. Start with the lowest fixtures and proceed in order to the highest.