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What to do during a power outage

Learn how to avoid a septic system disaster by conserving water when the power is out.



If you continue to use water by flushing toilets, washing dishes, or taking showers during a power outage, sewage may back up into the house!

Simple ways to be water-wise during a power outage

  • Take short showers.
  • Don't wash laundry.
  • Don't let the faucet run while brushing teeth, shaving, or rinsing dishes.
  • Don't flush the toilet each time it's used for liquid waste.

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On-demand pump system

  • Turn off

    Turn the circuit to the pump off while power is out.
  • Turn on then off

    Once power is restored, turn the pump on for 2 minutes and off for 4 to 6 hours. This doses the right amount of liquid sewage into the drainfield over a period. The pump may automatically turn off during the first manual dosing if there was little water use during the outage.
  • Conserve

    Conserve water and continue the 2-minute pumping every 4 to 6 hours until the pump turns itself off.

If you have a timer

A pump system with a timer controls the number of times the pump starts and stops. It manages how much effluent goes into the drainfield in a 24-hour period. Timers ensure the drainfield only receives as much effluent as it was designed to handle. The timer system will take care of itself once power is restored.

The as-built (scaled drawing of the septic system) may indicate if your system has a timer. It can usually be found on a wall or post near the pump tank or in the garage.

If the power has been off for a while, the timer will be behind. To allow your timer to catch up, continue to conserve water for another day or more.

If the high-water alarm sounds once power is restored, effluent has backed up into the reserve storage area of the pump tank. Refer to Steps 1 to 3 under the on-demand heading to start pumping backed-up sewage to the drainfield.