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Applications and permits

Find important permit information for your on-site septic/sewage system project.

Statewide OSS rule revision process

The Washington State Board of Health is revising the statewide OSS rules. You can learn more about this process, including how to comment, on the state Department of Health’s website: On-site Sewage System Rule Revision.

On-site sewage/septic system repair and replacement

A step-by-step guide for septic system repairs based on the permit you need.

Permitting for house or building remodels or expansions

Find the permitting steps for your remodels or expansions on septic systems.

Permitting for subdivisions and boundary line adjustments

Find the steps for permitting a subdivision or boundary line adjustment associated with a septic system.