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Carnation Treatment Plant

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

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

Inside the treatment plant, projects help us manage today’s wastewater flows, conserve energy, and increase performance. Carnation engineers and operators continuously scan the plant for energy savings. For example, in 2022 we completed several upgrades to overhaul the screens that are used to filter out trash and debris from incoming wastewater.

Contact us

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

4405 Larson Ave.
Carnation, WA 98041

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