On-Site Septic Program

The goal of the on-site septic program is to ensure that the public is not exposed to disease causing organisms, nuisances, or other pollution resulting from improperly operating on-site sewage collection and disposal. Environmental Health staff is charged with numerous responsibilities to ensure our waters remain free of sewage.

Planning to build?

Step 1: Soil and Site Evaluation
The parameters established in these reports guide the designer, engineer, or homeowner in the design of a on-site septic system.

Step 2: System Design
In Klickitat County the resident homeowner is allowed to design their on-site septic system if the site evaluation allows for a simple gravity system. For other systems, a licensed designer or engineer must design the system. A design is required prior to issuance of a septic permit, and a septic permit is required prior to issuance of a building permit.

Step 3: Construction
If the system is a simple gravity system, the homeowner may install. If you are not comfortable with installation practices or if your system is NOT a gravity system, you will need to hire a licensed installer. 

Step 4: Inspection and As-Built Records
Once the installation is complete, you or your hired installer will call for a final inspection. If everything is done correctly, the system is finalized. Once finalized, whoever installed the system will need to submit an "as-built" record prior to occupancy of the structure.

Step 5: Operation, Monitoring, and Maintenance
Once construction is done and all records are complete for the new system, the OSS owner is responsible for operating, monitoring, and maintaining the OSS to minimize failure. This may include evaluations and pumping every three years for standard gravity systems or yearly for other systems. This may also include securing service contracts for periodic maintenance on more complex systems. WAC 246-272A-0270 provides the complete list of owner responsibilities.