Skip to Content

Will Septic Tanks Work Without Power?

Will Septic Tanks Work Without Power?

Power outages happen all the time, especially if you live in a more rural part of the country. Although they usually don’t take more than a few minutes, some outages take up to a week depending on the severity of the damage to the infrastructure.

This begs the question: will septic tanks work without power? Is it wise to flush a toilet during a power outage, or is it best to wait until the power comes back on?

Will Septic Tanks Work Without Power?

Generally, no, septic tanks don’t work without power.

Unless you have a backup generator or a septic tank designed to run without power, the tank will continue to collect wastewater and remain stagnant until the power is restored.

Without power, the effluent won’t pump into the drain field.

What to Do Before, During, and After a Power Outage

Here’s what you should do before, during, and after a power outage to prevent septic tank complications.

Before a Power Outage

As with most unexpected situations, preparation is key. To prevent costly repairs and clean-up, consider the following:

Keep Your Septic System Well Maintained

It goes without saying that a healthy, well-maintained septic system withstands the stresses of a power outage better than a poorly-maintained system.

Routine maintenance not only lengthens the life of your septic system but also keeps your home safe from sewage backups.

Mound or sand filter systems, pressure distribution systems, and proprietary systems (i.e., aerobic treatment unit (ATU), membrane bioreactor (MBR), and drip irrigation) should be inspected annually. Gravity systems should be inspected every three or so years.

Document the connections and components of your septic system, as well as its general location, for replacement and/or insurance claims after the power outage.

Purchase a Generator

If your area is prone to constant power outages, high-powered generators are worth the investment.

Septic tanks require a high start-up wattage, so professionals recommend a minimum generator size of 7.5 kW in a residential setting.

Generators are fairly expensive, but the effects of a power loss can quickly multiply as days go by. If a septic tank becomes too full, sewer waste backs up in bathrooms, toilets, sinks, and drains. This not only causes a foul odor, but it’s also a real health hazard to you and your family.

Therefore, purchasing a generator is the best way to prevent any kind of backup during an outage. It’ll let you use your toilets and sinks as normal without worrying about it filling too much.

Install a Gravity Septic Tank System

Gravity septic tank systems, or gravity-fed systems, use gravity to send effluent out and into the soil instead of the pump.

Unlike other systems, gravity-fed systems don’t rely on electricity to pump out water.

They automatically sink the water waste into the surrounding soil once solids and liquids have been separated. The solids in the septic tanks are decomposed over time, whereas liquids are absorbed into the soil.

This type of septic tank is affordable, convenient, and relatively easy to service. However, gravity septic tanks aren’t for every household. Without the proper setup and terrain, the system won’t work. If it’s installed in less-than-ideal conditions, it’ll do more harm than good.

Furthermore, gravity systems are susceptible to earth shifts. Although it isn’t a problem for most people, earthquakes, and heavy weight can seriously affect the flow of the wastewater into the drain field.

During a Power Outage

Here’s what you should do during a power outage:

Reduce Water Waste

As mentioned above, wastewater will continue to collect in the system during power outages. For this reason, you should limit your water consumption to prevent overflow of the septic tank and pump chamber.

Here are some simple but effective ways to be water-wise during a power outage:

  • Take short showers
  • Don’t use your washing machine or dishwasher
  • Only flush the toilet when absolutely necessary
  • Don’t let the water run while brushing your teeth
  • If necessary, rinse your dishes instead of washing them
  • Install water-saving showerheads or flow restrictors

If you’re using a gravity-based system, the septic tank should operate normally during the power outage.

Even so, you should still be mindful of how much water you’re using, especially if you get your water from a well.

Although you’ll be able to use the water from the storage tank, you’ll be without water when it’s all used up until the power comes back on.

Monitor the Water Level in the Pump Tank

If the power outage lasts longer than a day, regularly monitor the pump tank water level.

If it’s over halfway full, call a pumper to remove the contents to prevent sewage backups inside your home.

After a Power Outage

In most cases, power outages, especially short ones, don’t cause too much damage to a septic system. Even so, it’s worth inspecting the status of the system to prevent future problems.

Inspect the System

For safety purposes, cut the power at the circuit breaker and unplug all power cords when inspecting the septic system. If any of the issues below are found, kindly call a service professional:

  • Unlevel ground
  • Damaged piping or manway covers
  • Odor or any sort of visible evidence of sewage
  • Exposed septic system components or pump wiring
  • Disposal field damage
  • Accumulation of sediments in the control box
  • Water leaking into the tank

Minimize Water Use For the Next Three Days

The aerobic bacterial community in the Aerobic Treatment Unit (ATU) reduces under anaerobic conditions, which results from a prolonged power outage. It’ll take a few days to reinstate the bacterial community that treats wastewater.

For this reason, avoid drinking water for the next three or so days until the septic tank has fully recovered its bacterial community in the aeration chamber.

Conclusion

Unless you’re using a generator or a gravity-fed septic system, your home’s septic tank won’t work without power.

Although power outages won’t affect the way your toilets, sinks, and showers work, it’s best to be water-wise during these situations. Since septic tanks still collect water during outages, you’ll want to reduce the amount of water you use until the power is back on.