Instructions – How to Chlorinate Your Well

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Materials – Unscented Clorox bleach – Well Sanitizing Tablets (drilled wells only) – Hose to reach from well to closest outside faucet – Wrench to remove well cap, pool test kit(to detect chlorine)

1. By-pass water treatment equipment if any.
2. Determine the well water depth & use the table/formula below to determine the volume of bleach to use.
3. Remove the well cap and determine if there is an unobstructed path from the top of the well to the water level. If you can’t see the water, drop a small pebble( tablet size) into the well and listen to hear if it hits the water. If the pebble hits the water, add the amount of bleach calculated in step 2 to the well. If pebble doesn’t hit water, determine what the obstruction is and remove it.
4. In order to mix the chlorine thoroughly throughout the entire water system, it is necessary to circulate the water in the well. This can be accomplished by connecting a hose to an outside silcock that is located after the pressure tank. Use the hose to run water back down the well. After a strong chlorine odor is apparent, rinse the inside of the top of the well and turn off the hose.
5. If you have a drilled well with a submersible pump, drop about 15 tablets for every10 feet the pump is above bottom of the well (most pumps are set at least twenty feet off the bottom of the well). This will assure that the area of well below the pump will be treated.
6. Open each faucet or service (don’t forget outside faucets, washing machine, ice maker etc.) and run the water until chlorine is present in water. Use the pool test kit to confirm the presence of chlorine. This procedure assures that all the water in the system is chlorinated. Make sure both hot and cold water lines have been filled with chlorinated water.
7. Allow the chlorinated water to stand in the system for at least (6) hours, preferably overnight. After this, connect a hose to an outside faucet and flush the water to an area that will not affect vegetation, streams or waterways. If this is not possible you will need to remove the chlorine from the water as you flush it. Flush until chlorine levels are less than 1ppm. Flush each faucet in the system once the chlorine is removed from the well.
8. After the system and well are flushed, put the water treatment equipment back into service. Test to be sure there is between .5 and 1 ppm of chlorine left in the water. This amount of chlorine should be enough to sanitize the equipment. You may perform a bacterial analysis on the water when you are sure no chlorine is left.

1. Do not use ammonia in fixtures before flushing chlorine because a poisonous gas will form.
2. Chlorine may break loose iron deposits, slime and organic material. This material will make the water run colored. The material broken loose may plug pump screens. DO NOT CONTINUE TO RUN PUMP IF WATER DOESN’T FLOW. This material may also plug faucet aerators and screens on appliances.
3. The high level of chlorine required to sanitize a water system is corrosive to most metals; therefore, chlorine solution must not be allowed to remain in water system more than 36 hours before being completely flushed from the system.
4. Some wells will recover fast enough to prevent the column of water above the pump to be drawn down to remove the chlorine from above the pump. If this is the case, you can connect two hoses to flush the well. One discharging into the well to circulate the water and the other discharging at the surface.

Well Diameter                         Multiplier (for 100 ppm)
6 inch                                        0.35
3 feet                                         18
4 feet                                         32
Depth of water in feet x ____ multiplier = _____ volume of bleach in ounces

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