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Phone numbers and office locations for our various departments are here. Thank you for your patience during the disruption.

Project documents

Find a variety of project documents such as project updates, newsletters, and environmental checklists.

Visit the public engagement page to view materials and information shared at meetings. Project updates are posted on the home page.

Fact sheets

Project overview: King County is upgrading a vital link in our water system! , May 2026
- King County 正在升级我们供水系统中的一个重要连接！
- King County हमारे वाटर सिस्टम की एक महत्वपूर्ण कड़ी को अपग्रेड कर रहा है!
- King County에서는 수자원 시스템의 핵심 연결망을 업그레이드하고 있습니다!
- Округ King County осуществляет модернизацию важного участка системы водоснабжения и водоотведения
The Plan for Trees , March 2021
Planning ahead for traffic changes during construction , May 2017

Environmental documents

Preliminary Tree Protection Plan , March 2019
We are updating this plan as we design the project. Some trees shown as protected may still need to be removed during construction. For every tree we remove, we will plant at least one new tree.
SEPA environmental checklist , issued August 15, 2018