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Decommission Permits

Apply for a decommission permit. Learn about applying for a decommission permit in the City of Portland in Multnomah County. Find out what's needed for a completed application. Get all required forms to decommission a cesspool, septic tank or seepage pit.

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When a septic decommission permit is required 

You need a septic decommission permit to shut down a septic tank, cesspool or seepage pit. The septic system will be pumped to remove all sewage and filled with sand, ¾” minus gravel. This permit also includes removal and proper disposal of septic tank containers.

You will need to decommission your existing system if:

  • A sewerage system becomes available and the facility the system serves has been connected to that sewerage system
  • The source of the sewage is permanently eliminated (for example, a structure is demolished)
  • New construction (for example, a home, addition, garage, ADU or deck) is proposed within 10 feet of an abandoned system
  • A land division is proposed on a property with an abandoned system
  • A property line adjustment is proposed that would result in an abandoned system being located on a different lot or within five (5) feet of the adjusted property line

NOTE: Septic Decommissioning IS NOT REQUIRED for a real estate transaction. Decommissioning is part of the negotiation between buyer and seller, and will require excavation of the existing yard.

Required decommission permit application and important information   

Apply for a septic decommission permit  

For a decommissioning permit, fill out the septic evaluation application. No plans are required. The application can be emailed to Onsite Septic Permits & Inspections.  

  • You must be both the owner and occupant of the house in order to do the work yourself
  • For other residential or commercial properties, a licensed State of Oregon, Department of Environmental Quality (DEQ) installer must do the installation

Staff will contact you with instructions on how to pay for your permit. Once the fee is paid your permit is issued. If you have any questions, please call Onsite Septic Permits & Inspections.  

Get ready for septic decommission permit inspections

When the cesspool or septic tank is pumped and filled with required material, you may call to schedule an inspection. Do not cover the the cesspool or septic tank until inspection has been approved. 

Schedule a septic decommission permit inspection, get inspection results and make corrections

To schedule an inspection, call the automated inspection request line. You will need your IVR or permit number and the three digit code for the inspection. Get the results of the inspection on Portland Maps permit/case search the next day. Read more about why work does not get approved and how to schedule a reinspection.

When the inspection has been approved, you may cover the cesspool or septic tank.

Contact septic inspectors

If you have questions about septic inspections, you can talk to an inspector between 7am – 8am on business days by calling Onsite Septic Permits & Inspections.


Building Code Plan Review

Development Services

phone number503-823-1456

Monday through Friday from 8 am - 5 pm. Leave a message with detailed information.

Onsite Septic Permits and Inspections

Development Services

phone number503-823-6892

Monday through Friday from 8 am - 5 pm. Leave a message with detailed information.

Requests for Inspection

Development Services

phone number503-823-7000

Automated Line - Requires an IVR or permit number