With the recent flooding, we are getting a lot of inquiries about what to do when your well floods.
Here is a recent question:
“We were flooded, so I had my drinking water tested just in case the well was contaminated.
It came out that I need to chlorinate my well due to coliform bacteria. I am looking for a company that can chlorinate or install a chlorinator for my well.”
We answered:
You might be able to find a local well or pump contractor to shock chlorinate and sanitize your well. Often they will do this type of well chlorination.
First, read our guide on “What to Do If Your Well Is Flooded.”
Floods-And-Your-Well-Water.pdf
After a flood, private well owners must carefully assess damage and hazards. Flood waters can contaminate well water, making it unsafe to drink and risking your health.
Start by inspecting your well for signs that flood or surface water entered the system. Look for visible mud, mud stains, or debris around the well casing. These indicate that contaminated water may have reached your well.
Ensure the well cap is securely fastened and not loose or damaged. A loose cap can let flood waters, bacteria, and contaminants enter. Do not try to fix issues if the area is wet or flooded.
Never touch electrical wires, controls near the well, or electrical components in flooded areas. Turn off the electricity to your well pump and water system. Wait several hours before inspecting or repairing. Contact a certified pump contractor or licensed electrician to check the well pump, pressure tank, and electrical system for damage.
Do not use well water for drinking, cooking, or baby formula until properly disinfected and tested. Use bottled water or boil tap water for at least one minute to kill bacteria and microorganisms. This prevents serious illness.
Be alert for sewage, heating oil, chemicals, or other hazards in the flooded area. If you detect any, do not clean it yourself. Contact trained professionals to handle hazardous materials safely.
Testing your well water is crucial after flooding. Contact a certified laboratory to collect a water sample and test for bacteria, heavy metals, and microorganisms. Test results will show if your water is safe or needs further treatment.
It is your responsibility to ensure your drinking water is safe. If unsure how to assess damage, inspect electrical components, or test your water, contact your local health department or a certified professional. Taking these steps protects your health and ensures safe, well water after a flood.
Do not take risks with contaminated water. Follow all safety and testing guidelines to keep your family safe after flooding.
Make sure to test for coliform bacteria.
If you need to install a chlorinator, there are several choices, including pellet feeders that feed chlorine pellets down the well or liquid chlorination.
Liquid chlorination using chlorine bleach and a contact tank to allow time for the bacteria to be killed is often the safest and lowest-cost method. Here is more information on those types of systems:
For well decontamination after flooding, consider the following steps: First, measure the depth of water in the well to calculate the total volume for proper chlorination. You may need to fill the well and pump water out as part of the cleaning process. After adding chlorine, run water from an outside faucet (not an inside faucet) to flush the system thoroughly and prevent contamination from entering the household plumbing.
Chlorine offers a low-cost, safe way to eliminate odors and bacteria. It also effectively oxidizes iron, manganese, and other contaminants, making them easier to filter out.
While you can use other methods to remove microorganisms and odors from water, chlorination remains the most popular option due to its affordability and proven effectiveness.
Often combined with filtration, chlorination is an excellent and cost-effective way to disinfect drinking water supplies, eliminate odors, and oxidize iron and other metals.
For easy and accurate chlorine injection, we recommend a J-PRO pump and solution tank system.
The chlorinator uses liquid chlorine bleach. The system is reliable, easy to install, and very easy to use. It can be adjusted to get just the right amount of chlorine needed for the application.
The chlorinator can be adjusted so the chlorine levels are very low in the household (similar to city water), or a low-cost carbon filter can be installed to remove any trace of chlorine tastes and odors.
A contact or retention tank provides optimal contact time after chlorine has been injected into the water.
By using a contact tank, the amount of solution needed is less, and ensures that the solution being injected is thoroughly mixed and dissolved in the water.
Most importantly, a contact tank allows sufficient time for the bacteria to be killed after the chlorine is injected.
If your well has been flooded, it’s important to take immediate action to ensure your drinking water is safe.
Note: Always check your specific state’s health department website for the most accurate and localized guidance, as procedures can vary.
Yes, flooding can contaminate your well water with bacteria, chemicals, and other pollutants. It’s important to test your well water after a flood.
Absolutely. Floodwaters can carry pathogens and debris into your well, compromising water quality and posing health risks.
Yes, prolonged or intense rainfall can increase the risk of surface contaminants seeping into your well, especially if it’s shallow or poorly sealed.
If floodwaters have covered your wellhead or if the water is discolored, smells, or tastes different, your well may have flooded and should be tested.
Runoff from agricultural fields, septic systems, and chemical spills can all affect well water quality during flooding.
Yes, it’s recommended to boil your well water or use bottled water until testing confirms it’s safe to drink.
No, well water should not be consumed without boiling or proper disinfection until it has been tested and cleared.
Boiling kills harmful bacteria and viruses that may have entered your well through floodwater contamination.
Boil water for at least one full minute (or three minutes at higher altitudes) to ensure it’s safe to drink.
Stop using the water, have it tested, and consider hiring a licensed contractor to shock chlorinate and sanitize your well system.
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