The Washington State Department of Health requires that there is ongoing operation and maintenance (O&M) of all septic systems.  Cowlitz County allows homeowners to perform their own operations and maintenance inspections on most system types.

Operations and maintenance is required on septics using gravity distribution only once every 3 years. Homeowners may perform their own operation and maintenance inspection on this type of system without training from the county. Cowlitz County recommends that the inspection be performed annually.

All other types of septic systems must have an operations and maintenance inspection at least annually.  For any of these systems that does not incorporate a patented product (other than gravelless chambers) the homeowner may perform the inspection after attending a class presented by the County.

On the right side of this page are links to some frequently asked questions as well as informational pamphlets, a list of licensed professionals, and the forms that need to be completed and submitted to the county. 

The County will be providing the training at least once per quarter.  The trainings are currently being presented in conjunction with WSU cooperative extension office.

If you have any questions about septic systems or operations and maintenance inspections you can email them to: omseptic@co.cowlitz.wa.us