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Pump systems depend on electricity to move sewage into drainfields. When the power is out, you will need to conserve water.


If you continue to use water by flushing toilets, washing dishes, or taking showers during a power outage, effluent 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


On-demand pump system

The most common pump system, the on-demand pump begins its cycle when sewage reaches a pre-marked level in the septic tank and sewage is pumped into the drainfield.

During a power outage, effluent stops being pumped into the drainfield. The septic and pump tank will collect wastewater and release it once power is restored. Too much water pumped into the drainfield will flood the drainfield and lead to complications.

Follow these steps to avoid complications:

  • Turn the circuit to the pump 'off' while power is out.
  • Once power is restored, turn the pump 'on' for 2 minutes and 'off' for 4-6 hours. This "doses" the right amount of effluent 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 water and continue the 2-minute pumping every 4-6 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 time 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 an additional 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 1-3 under the on-demand heading to start pumping backed-up sewage to the drainfield.