Permitting process

Having safe a safe and reliable water source is an important first step when developing a property. On-site sewage systems or homes cannot be built or expanded if they don’t have water from an approved water source.

When people apply to King County for on-site sewage system permits, building permits, and boundary line adjustments or subdivisions, the applicant must show they can use approved water source. Water sources are approved by either Public Health – Seattle & King County or the Washington State Department of Health’s Office of Drinking Water.