On-site sewage/septic system program
The Public Health – Seattle & King County On-site Sewage/Septic System Program helps make sure that over 85,000 sewage/septic systems in King County are safe. Sewage/septic systems treat wastewater when homes and buildings are not connected to public sewer systems. We also provide permitting and educational services for owners of septic systems, and certifications for some septic professionals.
Resources for homeowners and residents
Find sewage/septic information for homeowners and residents.
Resources for on-site sewage/septic system professionals
Professionals need Certificates of Competency to work on and maintain septic systems. Learn more about becoming certified or renewing your certification.
Resources for real estate professionals
Find sewage/septic information pertaining to real estate.
Search on-site sewage/septic system records
The online database has King County's official records. You can also find the record drawing search utility, King County iMap, and other resources.
Maintaining your on-site sewage/septic system
Sewage/septic system owners need to have their system inspected regularly. Learn more about proper sewage/septic system care.
Financial assistance
Learn more about loans or grants for on-site sewage systems.
Property sales and transfers
Find information for buyers and sellers of properties with on-site sewage/septic systems. Buyers and sellers both have responsibilities during a sale.
Applications and permits
You must have a permit to install, repair, or replace an on-site sewage/septic system. Find more information about permits and applications.
On-site Sewage System Technical Advisory Committee
The On-site Sewage/Septic System (OSS) Technical Advisory Committee brings together industry partners and impacted parties to participate in OSS policy development and problem resolution.
Healthy beach project
Learn how the Vashon-Maury Pollution Identification and Correction Project helps you, and how you can help.
Marine Recovery Area
Learn about the importance of a Marine Recovery Area, the areas impacted, and how it affects you.