Knowledge Base

Septic Tank Effluent Pump (STEP) Systems

A Septic Tank Effluent Pump, or STEP System, screens out solid waste and pumps wastewater to the City’s sewer line for further processing at the Lacey, Olympia, Tumwater and Thurston County (LOTT) Clean Water Alliance Wastewater Treatment Plant
The property owner is responsible for the sewer line that runs from the house to the STEP system. The City of Lacey maintains the system itself. Because the City owns the STEP system and it is considered part of the City's utility system, there is no requirement to have the system pumped if you sell your home.

The STEP tank and pump are buried in the yard and are controlled by an electrical panel on the side of the house. The wastewater from the home flows into the septic tank where solids settle and form sludge on the bottom of the tank. The liquids flow through a screen and are pumped into the City's sewer line for transport to the LOTT treatment plant.

The City of Lacey maintains the STEP system every eight years. The maintenance includes a full inspection and pumping. When crews arrive to perform preventative maintenance on a STEP system, they will first knock on the door to let you know they will be working. 

Diagram of STEP System

Caring for you STEP system:

  •  Maintain at least a 3-foot clearance around the green tank lid(s) in your yard and a clear path to the control panel on the side of your home. Without clearance, crews maybe unable to perform maintenance.
  • Never drive or park anything on top of your STEP system.
  • Ensure that water, toilet paper, and human waste are the only things that go down the toilet and drains.
  • Do not add septic aid products to your system or put chemicals down the drain.
  • Excessive use of your garbage disposal can clog your system. Throw away or compost excess food, coffee grounds, eggshells, fats, oils, grease, etc.
  • Locate the STEP system's breaker in the home's electrical panel. Make sure this breaker is on at all times. If the breaker is turned off or trips, there will be no power to run the pump and you could experience sewer backup or overflow.
  • If your tank lid becomes damaged, secure the area and report it to the City of Lacey Maintenance Service Center at (360) 491-5644 as soon as possible.
  • Call before you dig. Its the law! Do not dig around your tank unless underground utilities have been located. Homeowners can request utility locates by calling 1-800-424-5555 (or *811 on your cell phone) or online at

If your STEP system alarm goes off:

  • You will hear a loud alarm, similar to a car alarm, coming from the control panel located on the side of your home.
  • Press the red button to silence the alarm. The red light will remain on while the alarm is active.
  • Restrict water use by not running your washing machine or dishwasher until City crews can determine the cause of the alarm. As long as sewer is not backing up in the home, brief showers and toilet flushing is okay.
  • Immediately report the alarm to the City of Lacey Maintenance Service Center at (360) 491-5644 during business hours or at (360) 704-2740 during nights/weekends.

If sewer is backing up inside of your home:

  •  Immediately call the City of Lacey Maintenance Service Center to contact our wastewater staff at (360) 491-5644 during business hours or at (360) 704-2740 during nights/weekends. Technicians are available 24/7, 365 days a year to respond to sewer emergencies.
  • Do not use your washing machine, dishwasher, take showers/baths, or flush water down drains or toilets until crews can determine the cause of the overflow.

If the power goes out:

  • Restrict your water use and do not use the dishwasher or washing machine and do not take showers or baths until power has been restored. You can flush the toilet unless you have sewer backing up in your home. If this occurs, call the City of Lacey Maintenance Center immediately for assistance (360) 491-5644.
  • The STEP tank has reserve storage capacity that should be sufficient if you limit your water use.
  • If you notice a sewage overflow or experience back-ups, immediately notify the Lacey Maintenance Service Center.
  • When the power comes on again, it is normal for the alarm to go off. Silence the alarm (by hitting the red button on the control panel) and check the alarm panel again after 30 minutes. If the alarm light is still on, contact the Lacey Maintenance Service Center for assistance.


Updated 3/26/2024 11:53 AM
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