Creating or expanding a public water system

King County does not review nor approve new or expanding public water systems. Instead, the WA State Dept. of Health's Office of Drinking Water reviews and approves new or expanding Group A and Group B water systems. New and expanding public water system projects must be led by a professional engineer specializing in water systems.

• Learn more about Group A water system requirements, WA State Dept. of Health
• Learn more about Group B water system requirements, WA State Dept. of Health