How to Protect Your Septic System and Well During a Flood

Flooding can damage your septic system and well, and it can lead to serious health risks. 

Follow these steps before, during and after a flood to stay safe and protect your water system.

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Protecting Your Water System

  • 1

    Before a Flood: Get Ready

    Keep your system in good shape.

    • Make sure your septic tank and drainfield are working properly.
    • Fix any leaky sinks, toilets or pipes.
    • Keep stormwater from flowing over your septic system if you can.

    Prepare and secure your septic system.

    • If your system has a backwater valve, check that it works. Close it if it's manual.
    • Don't fully pump your tank before a flood. An empty tank can float out of the ground!
    • Plan to use less water during a flood. Limit showers, laundry and flushing.
    • Tighten and seal any access points like cleanout caps or tank lids.
  • 2

    During the Flood: Stay Safe

    Stop using your septic system.

    • Avoid flushing the toilet or using sinks, washing machines or dishwashers.
    • Don't run water softeners or sump pumps into your septic system.
    • Turn off power to septic pumps and alarms.

    Watch for signs of trouble.

    • Drains may slow down or back up.
    • Basement or lower-level drains might overflow.
    • If your well is underwater, the water might be contaminated. Don't drink it!
  • 3

    After the Flood: Wait Before Using Your System

    Don't use your septic system yet. Wait until the ground is no longer wet or flooded over the tank or drainfield.

    Check for damage

    • Look for sunken soil, sewage surfacing or a strong sewage smell.
    • Call your local health department if you suspect damage.

    Get your system inspected

    Protect the drainfield

    • Don't drive, park or store heavy items over the drainfield area.
    • Fix any erosion and plant grass to help the soil recover.

    Be careful with cleanup

    • Wear gloves, boots and eye protection to clean areas touched by sewage.
    • Throw away anything you can't disinfect.
    • Never dump floodwater or cleaning chemicals into your septic system.

What About My Well?

Wellhead

Before the Flood

  • Store plenty of clean water for drinking and cooking.
  • Turn off power to your well before floodwaters arrive.
  • If your well doesn't have a tight seal, cover it with a heavy-duty bag and tape it shut.
  • Find your well records and save them in a safe spot.

After the Flood

  • Do not drink well water until it's tested, even if it looks clear.
  • Use bottled water or boil water for five minutes before use.
  • Contact a certified well contractor.
  • Call your local health department to get your water tested for bacteria and chemicals.