Safety
AROUND YOUR HOME

Disinfecting water lines and wells

Living in a rural area many times means using a well for a water supply. Sometimes there are concerns about water quality, and questions arise on how to check the water to see if it is free from bacterial contamination. If testing does show bacterial contamination, disinfecting the water lines can be done by shock chlorination.

Duane Friend

Testing the water is the first step to take. Private water testing labs can test for bacteria, nitrates and other possible contaminants, There are several private water-testing labs in Illinois. Costs will depend on the type of testing to be done, and it is probably a good idea to contact several labs to compare prices. Local health departments will usually test water systems for bacterial contamination in new houses, or bacteria and nitrates when a new-born is present in the home. Testing in these cases is usually free. The Illinois State Water Survey can test water for a broad spectrum of minerals and nitrates, at their public services lab. Most tests at this lab are also free, and technicians will advise on ways to correct a water problem.

To disinfect a well contaminated with bacteria, a disinfectant such as chlorine tablets or chlorine bleach will work. For drilled wells, the top of the well casing will have to be disassembled. For dug wells, simply open the cover and add the disinfectant. The amount of disinfectant required is determined by the amount of water in the well. For example, a well 5 feet in diameter that has 30 feet of water would require 8.5 gallons of bleach. A table that shows the amount of chlorine to use is available in local Extension offices. The chlorine should be added to about 10 gallons of water and poured into the well, covering as much of the walls as possible.

All faucets in the home should then be turned on until a strong odor of chlorine is noticeable at each faucet. Afterwards, water flow should be stopped for at least 12 hours. It is usually easiest to do this as a late evening and overnight activity.

After allowing the chlorine to sit in the lines, all the faucets should be opened until the chlorine odor disappears. Faucets that drain into septic systems should only be turned on to low flow, to avoid overloading the system.

Once this procedure is completed, the water should be used for a week or two, then tested again. If contamination is again present, the source for the contamination must be determined and corrected before the water supply will remain sanitary. Shallow dug wells have a greater chance of being contaminated compared to drilled wells, simply because they are more susceptible from surface contamination. A licensed well contractor or plumber may be needed to locate the source of contamination.

Local Extension offices can provide more information on disinfecting wells and water lines. To contact the Illinois State Water Survey Public Service Lab, call (217) 333-9234 or (217) 333-0802.

Seal abandoned wells To protect the ground water in your area, remember to seal abandoned wells. Here are 10 good reasons why you shouldn't put this off. 1. Groundwater protection - Wells are a direct route to the aquifer. 2. Safety - People and pets can easily fall into them. 3. Water supply protection - Especially nearby wells. 4. Pesticide use - Not within 50 feet. 5. Peace of mind - No safety or groundwater hazard. 6. Potential liability - If an accident or contamination should occur. 7. Aesthetic value - Abandoned wells are not a pretty sight. 8. Restore the environment - Some old pumps may be valuable. 9. Responsible transfer of land - Before selling, wells should be sealed. 10. It's the law!!

Duane Friend is the natural resource management educator at the Springfield Extension Center, University of Illinois Extension. You can write to Friend in care of Illinois Country Living, P.O. Box 3787, Springfield, IL 62708. Telephone (217) 782-6515.

14 ILLINOIS COUNTRY LIVING JANUARY 2000