Authorization Notice

Do I need an Authorization Notice?

An Authorization Notice is required when you propose to reconnect to an existing septic system, when there is an increase in flow, when there is a change in use (from residential to daycare, for example), or when a temporary dwelling is needed for hardship reasons*.


To apply for an Authorization Notice, submit an Existing System Evaluation Report (ESER) from a DEQ certified provider. If no previous records are available you will also need to provide a Record Drawing and Installed Materials List from a licensed septic installer or consultant.

System components may need to be uncovered for soils staff review if:

  • If the maintenance inspection report is in dispute by the county or property owner.
  • If there are no records on the system and the materials in the system are not consistent with a system installed prior to 1974
  • The new proposal (foundations or partition, for example) appears to conflict with minimum required setbacks to septic components (5 ft to the tank and 10 ft to the drainfield).

Evaluation Results

Based on the Inspection Report, we may require that the septic components be moved, replaced or supplemented. Any septic system construction will depend on the analysis of the test pits and other site conditions. Other than maintenance (pumping the tank or removing roots from any components) all work on the septic system must be done under a permit.

Altering the septic components

Minor changes to a septic system can be done under an alteration permit. If more than 50% of the drainfield is affected or if there is an increase in flow greater than 300 gallons per day or 50% of the system capacity (whichever is less), a site evaluation, rather than an authorization notice, is required and new construction permit, rather than an alteration permit will be required.

Repairs to the existing system

If system components are found to be in need of repair or replacement, a septic repair permit will be required. Test pits may be required for repairs to drainfield components.

Clackamas County Septic and Onsite Wastewater
150 Beavercreek Road
Oregon City, OR 97045

*Medical hardship Authorization Notices are required every 5 years as per OAR 340-071-0205


150 Beavercreek Road 2nd floor Oregon City, OR 97045

Office Hours:

Monday, Tuesday, Thursday  
8 a.m. to 4 p.m.

Available by phone/email  
8 a.m. to 4 p.m.  
8 a.m. to 3 p.m.