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Vashon Treatment Plant

King County Wastewater Treatment Division continuously looks for ways to keep the Vashon Treatment System efficient and reliable. We regularly inspect features and when necessary, design and build projects to:

  • Meet updated regulations
  • Save energy
  • Improve water quality
  • Improve efficiency and reliability
  • Repair, replace, or upgrade equipment which has come to the end of its life

There are currently no projects anticipated at the Vashon Treatment Plant in 2023. We will update community members if any unplanned maintenance work pops up over the course of the year.

Contact us

24 hour emergency and odor reporting:   206-263-1760
Administration:  206-463-7318

9615 S.W. 171st St.
Vashon, WA 98070

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