How to chlorinate your water well (revised 8-4-11)

Well Chlorination Instructions

From time to time, (every six months to a year) it is a good idea to chlorinate your well. We do this NOT necessarily to kill "bugs", (although it can be used for that purpose) or because a well is "contaminated", but to oxidize some of the natural minerals that occur in well water. These minerals are NOT hazardous, matter of fact, your body is made up of these naturally occurring minerals such as: iron, calcium, magnesium and other trace minerals. To refuse to drink your own well water, then run to the store to buy bottled water with a label that says "natural minerals added!" is truly an amazing activity. The best drink of water comes from under your own land, out of your own private, untaxed, independent water well that YOU own and control. These natural minerals are fairy easily removed and odor is easily removed, (even in the Northern townships), and we can make your well water rival even the best tasting bottled water.

If you are chlorinating your well for a health department test, the procedure is slightly different than if you just want to chlorinate as a maintenance measure.

1A. If chlorinating for a health dept. test, start here. Call the health dept. On a Wednesday or Thursday to set up a time for them to come pull a sample the following week. You CAN NOT chlorinate and have the health dept, (or anyone else) pull a sample the very next day. You should begin your chlorination procedure a MINIMUM of 72 hours before your water sample appointment.

1. If chlorinating just as a maintenance procedure, start here. Take the lid off of the well, (or if it is well seal in a pit, sometimes there is a "vent hole, or pipe to put the chlorine in) and pour 2-5 gallons of regular Clorox down the well casing. (On very rare installations, the electrical pressure switch is 2-4 feet down from the top of the casing. If you have one of these, take a 1" pipe, put the pipe down past the pressure switch, and pour the Clorox in, taking care not to spill it on the switch).

2.Take your garden hose from an outside faucet,(preferably not through the water softener) and put it down the well casing, turn the hose on and let run for 1 minute. Shut hose off. Wait 2-3 minutes for all the rust that you just knocked loose from the black steel casing (this is one reason that Hardman Drilling has never used black steel casing), to filter down past the pump. If you have a white plastic casing, or galvanized (silver colored) casing, you can leave the hose run. Turn the hose back on and recirculate the water down the well for 20-30 minutes.

2A. IF you are chlorinating for a Health Dept sample, run the water out all the cold water faucets until you smel chlorox strong, then shut them off. If it's your yearly well chlorination for maintinance, don't run the faucets in the house.

3. After 30 minutes, shut hose off, put lid back on well and try not to use any water, (except for flushing toilets) for 12 hours.

4. After the 12 hours, attach the garden hose to the bottom of the pressure tank hose bib (most tanks have one on the plumbing somewhere)and turn the hose on, wide open with no spray end or anything on the end of the hose, and let run for at least 2 solid hours (6 is better). Running the water through an outside faucet on the side of the house is a distant second in where to run it off, but the bottom of the pressure tank is the best place.

5. If After you run the water off at the bottom of the pressure tank for 2-6 hours, you still have chlorine smell, take a hose from an outside faucet and run back down the top of the well casing at the same time you are running the water off at the bottom of the pressure tank. This will drive the chlorine in the well bore down to the pump suction intake to be pumped out of the well. Do this for an hour or until you don't smell chlorox anymore.

6. If you are just chlorinating as a maintenance procedure, you are done. If you are having the health dept coming to pull a sample, just use the water normally until the appointment. DO NOT open or disturb the well in any way after the chlorine has been run off.

As a piece of information, if your well has a "conduit" cap, (these are usually silver or red, and have Allen wrench type set screws, or 4 sided bolt heads usually up under the cap), then you have an "unsealed" cap. If your well tested "positive"** or "bad" for total coliform, (the test that the health dept. takes), it’s pretty safe bet that you also noticed spiders, earwigs, or wasps building underneath the well cap when you took it off to chlorinate, and this is why you are failing the test. Have us, or another registered well professional put on a "bug resistant", sealed cap for you. This can be done for less than $100.00, and might be the best investment that you can make in your well. The water in the well can be fine, but if you have insects building in the well lid or cap you never will get a "safe" sample.

**If the test comes back positive, you will get a letter in the mail from the Health Dept. stamped with big red letters "unsafe for human consumption". To fully understand what this means, let’s look at what the test actually measures. The test is for "total coliform". This is a measure of not only pathogenic (bacteria that can make you sick), but also NON pathogenic coliform bacteria. There is also a bacteria called "pseudomonas" that can give the test a false positive. Also in some circles, there is talk that common iron bacteria can trigger a false positve in some cases. The MMOMUG test can’t tell the difference. There may be nothing wrong with the water in the well. If this is a new house, the plumbing (pipes) that are permanently installed in your house have been lying around in the warehouse for months, and insects, etc. have been crawling through them. This can give you a "bad" or "positive" test. Also, this test is sensitive to chlorine, and if you didn’t get all the chlorine run off before the sample was taken, this, too, can give you a "bad" or "positive" test. To pass this test, we have create a condition in the well and piping that very seldom occurs in nature: a bacteria free environment. To give a reference point: the wash rag that is hanging in your kitchen sink has far more bacteria on it than the well probably ever will have. Think about it: you washed off the counter where the cat jumped up after using the litter box (you didn’t see her), and you regularly wash off fresh fruits and vegetables in your sink (you didn’t use the washrag, but it was hanging in the vicinity). We live in a world of bacteria.
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Tel: 419-289-9405
If No Answer, Call: 419-281-3334
Fax Number: 419-903-0420
639 County Road 1302
Ashland, OH 44805-9778
United States of America