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Other agency services

Learn where to go for King County permits that are not handled by Local Services.

Septic system permits

Septic systems treat wastewater when homes and buildings are not connected to public sewer systems. A septic system is also referred to as an "on-site sewage system" (OSS) in official documents, forms and applications. 

Learn more from Seattle and King County Public Health

Road vacation petitions

A road vacation allows adjacent property owners to reclaim unopened King County right-of-way in accordance with the provisions under RCW 36.87. Procedures to file a petition to vacate right-of way before the King County Council are outlined under Section 14.40.020 of the King County Code.

Learn more about road vacations in unincorporated King County 

Hydraulic Project Approval

A Hydraulic Project Approval is required when any construction activity in or near state waters is proposed. State waters include all marine waters and fresh waters of the state. This permit is issued by the Washington State Department of Fish and Wildlife (WDFW),

Learn more about Hydraulic Project Approvals from WDFW

Changes to landmark properties

Significant historic and archaeological properties in unincorporated King County including buildings, sites, districts, objects, and structures are protected by certain design review processes and may be eligible for certain incentives.

Any major restoration or changes of a significant feature of a designated King County Landmark property in unincorporated King County requires a Certificate of Appropriateness (COA), which is granted through a design review process. "Landmark" refers to a physical property that has been formally designated and listed on a register of historic places by an agency of government.The COA process is separate from the building permit process. COAs must be obtained through the King County Historic Preservation Program before building permits are issued. Some projects that do not require building permits may still require COAs. Design review may result in changes to the project specifications; the Historic Preservation Program recommends applying for a COA prior to finalizing your plans.

Learn more about Certificates of Appropriateness (COA) through the Historic Preservation Program

Stormwater permits

The Washington State Department of Ecology (DOE) issues stormwater permits. These permits address legal requirements and control the discharge of pollutants to protect surface water and ground water quality in Washington State.

Stormwater is regulated in Washington State by several types of permits. The permits are designed to control runoff related impacts from various types of sources: