Official sources checked August 31, 2026

Grant County, Washington septic permits and requirements

Washington state/local framework

Washington Department of Health states that the local health officer has regulatory jurisdiction over onsite sewage systems with design flows from 0 through 3,499 gallons per day. Local health jurisdictions permit and manage those systems and may administer local codes that are more protective than the statewide minimums.

Health District permitting authority

Grant County Health District states that it oversees the design and installation of onsite sewage systems with wastewater flows under 3,500 gallons per day and performs permitting, inspections, complaint investigations, site/design reviews, and development review.

Permit required before installation, changes, or repair

GCHD states that anyone installing, changing, or repairing an onsite sewage system must first obtain a Health District permit. The county process requires site and soil evaluation and submission of the application, complete design, and site plan.

County building permit first for county-jurisdiction properties

GCHD specifically states that it cannot accept a new septic application for a property under Grant County authority until the applicant first applies for the Grant County building permit. This sequencing requirement is important for county-jurisdiction projects.

Installation permit validity under the revised rule

Grant County Health District states that installation-start permits for designs approved under the revised onsite rule expire after two years rather than one year. Applicants should verify the current permit dates shown on their approval before scheduling construction.

Certified professionals and maintenance providers

Most onsite systems must be installed by an installer certified through GCHD. The Health District also requires septic maintenance service providers to obtain local approval; beginning January 1, 2026, those providers must show proof of passing the listed WOSSA O&M Level 2 Specialist examination before county certification.

Current fees

Grant County Board of Health approved a 2026 fee schedule effective July 9, 2026. Because onsite fees vary by service and system type, the page links directly to the current Health District schedule rather than hard-coding amounts that may change.

Official sources

• Washington State Department of Health — Regulatory Jurisdiction
• Washington State Department of Health — OSS Management Roles
• Grant County Health District — On-Site Septic Systems
• Grant County Health District — On-Site Septic Applications
• Grant County Health District — Septic Service Providers
• Grant County Health District — 2026 Fee Schedule
• Grant County — Permits

SepticScope summarizes public-agency information for planning purposes. The permitting agency's current instructions control if they differ from this guide.