The history of our mission

In the 1950s, wastewater flowed largely untreated into Lake Washington and Puget Sound and many rivers and smaller lakes, fouling water and making a sullied mess of local beaches.

In 1958 the voters created Metro and developed a regional wastewater treatment system based on watersheds as opposed to political boundaries.

Shortly after Metro was formed, construction began on the county's two existing regional treatment plants, West Point in Seattle's Magnolia neighborhood and South Treatment Plant in Renton, which were officially up and running by 1966. By the late 1960s, regional water quality began improving dramatically.

In 1994, King County assumed authority of Metro and its legal obligation to treat wastewater for 34 local jurisdictions and local sewer agencies that contract with King County.