Saturday, August 1, 2009

Should I chlorinate / bleach my well ?

Almost anyone that has a well has either already done it or heard about doing it. So what are the benefits of bleaching your well water ? Are there any drawbacks ? Will it hurt my pump ? How much bleach should I put in my well ? Is there a proper way to do it ?



First of all, the benefits are quite simple and obvious. By chlorinating your well you disinfect the water and kill any bacteria. Secondly you are also getting rid of any odors in the water and knocking the rust out of the water, but this is only temporary. Why ? Because the water feeding your well will eventually re-contaminate the water again. Picture your well like a test tube with a big bubble at the bottom. Kind of like one of those beakers you used in chemistry class with a long neck. The long neck represents the well casing and the bubble part is the part that holds all of the water. All wells have a way to replenish themselves with water through veins in the earth. Some wells actually have a river of water feeding it, but those type are more rare. I mention this because in most states, a mortgage loan cannot close if the well water is contaminated with bacteria. So what happens ? The current homeowner bleaches the well and gets a negative test for bacteria and then the loan closes. Problem is, the new homeowner moving in has no idea that the well will be contaminated within 2-3 months, and in some cases I've seen re-contamination in weeks. With all of the above in mind, here are the proper steps to chlorinate your well.

1. Remove the cap from the well casing or take the plug out of the well seal at the top (in which case you will have to use a funnel) To take the well cap off, just loosen the set screws and tap it off with a hammer.

2. If you have any water treatment equipment (softener, iron filter, etc.) bypass it now. Heavily chlorinated water will ruin most equipment. If you have a reverse osmosis system, shut it off.

3. Make sure to use a safe bleach or NSF approved bleach for your well.  Most household bleach contains a lot of additives and should be avoided.  The best I have found is called Well Safe well sanitizer pack, and is made by Better Water Industries.  You can buy it HERE.





4. After you have added the proper amount of chlorine, take a garden hose from the nearest outside faucet or the faucet that is closest to you. Put the other end of the hose into the well casing. Turn on the water and let it run to wash down the inside of the well casing. Keep it running until you get a strong smell of bleach coming out of the hose. When you do, turn off the hose.

5. Now you must disinfect the lines in the house. Start with any faucet and turn on the cold water until you smell bleach. Proceed to EVERY faucet in the house and run them individually until you smell bleach. You can run the hot water also, but this will take longer to get the bleach through the hot water tank. After you have completed this process, let the bleach sit in the well and house lines for 8-10 hours minimum. If you can let it sit overnight, fine.

6. After your 8-10 hours, start with flushing off the well. After the smell of bleach is gone, and the water is clear, then flush the lines out in the house. Keep in mind that when wells are bleached, the water can turn bright orange, black or brown. I have seen many different colors of water after it has been chlorinated. Some only take 1-2 hours to clear, other can take 4-5 hours or longer to clear. Keep this in mind while your flushing off the well.

7. Run the water into a white bucket to make sure that it is clear. Once your sure, turn your water treatment equipment back on.


The worse your water is laden with iron, manganese and the likes the worse the color of the water will be. Remember, if your buying a house and the well was chlorinated, be prepared to spend the money to install water treatment equipment that will continually disinfect the water.  As always, feel free to contact me with any questions.

The Water Guy