Water Wells: 7 Things to Do AFTER a Flood
Flooding puts both public and private water systems at risk, but the threat to private water wells is greater. Homes with wells are more likely to be situated in rural areas where households rely on septic systems and land is used for crops and livestock.
Flood waters are likely to be more heavily contaminated with chemicals from fertilizers, herbicides and pesticides, waste from animals and flooded septic systems, and pollutants like gasoline, diesel and heating fuel.
Even if your property wasn’t flooded, the groundwater source may be contaminated. Here are seven critical steps to take to help restore basic functionality:
- Test the water with a home test kit to determine if your water is contaminated. (Yes, you should always have a supply of test kits on hand.)
- If the water is contaminated with bacteria, stop drinking it and use only bottled or stored water for food preparation and baby formula. Remember boiling can kill bacteria but concentrate chemical contaminants. Limit your exposure through bathing, showers, etc., until the well is decontaminated.
- Disinfect the well using unscented household bleach or hypochlorite granules. (Chlorine pool tablets take longer to flush out of the system.) Take filter-based water treatment systems offline, and drain or directly sterilize water in hot water tanks.
- To simultaneously clean the well, pump, wiring and plumbing system:
- Mix water and bleach in a bucket. As a general guideline, use 1 to 1.5 cups of bleach for every 30 feet of depth (standard 6-inch cased well).
- Remove the well cap and pour the bleach mixture into the well.
- Attach a hose the nearest outside faucet. Let the water run until you smell chlorine.
- Put the running hose into the well. Spray water down the well pipe for 15 to 20 minutes to recirculate chlorine into the system.
- Turn on all interior faucets and flush toilets. When you smell chlorine at the farthest faucet, turn them off.
- Turn off the pump, let the chlorine sit in the system for 8 to 10 hours, and don’t use the water.
- Drain the chlorine from the system. Turn on an outdoor spigot and let the water run until you can no longer smell chlorine. Use a hose to direct water away from your well and septic system.
- Turn on indoor faucets and let them run until you no longer smell chlorine.
- Wait 3 to 4 days, then retest. In the interim, use well water for bathing, laundry and cleaning, but not for drinking, food preparation, baby formula, ice or brushing teeth.
- If the test results are satisfactory, you can return to normal usage. If the water still contains coliform bacteria, repeat the disinfection process.
- Continue to test water for several weeks, because as flood waters recede new contaminants may enter the groundwater and recontaminate the well.