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To learn about Sound Transit's current and planned projects explore the new System Expansion interactive map. This website is no longer being updated.

Document library

Dive into the details and find helpful information in the links listed below. Types of materials that are available include: detailed project information, Board of Directors materials, environmental documents and technical reports. Documents may include graphics and drawings based on the early stages of design. Designs are subject to change as the project progresses. Not all project documents are available online. Contact us if you have questions.