East Link Extension
Seattle, Mercer Island, and Bellevue, Washington
The Watershed Company, as a subconsultant to WSP, provided extensive assessment, permitting, and mitigation design in support of Sound Transit’s extension of rail lines from Seattle's International District to the Puget Sound region’s eastside. Spanning more than six and a half miles, the extension travels across Mercer Island and to Bellevue with two stations and six other infrastructure locations for power transfer and switching. Watershed scientists conducted a large-scale critical areas review of all wetlands, wildlife, and a comprehensive tree inventory that included species, size and health, and GPS-located all significant trees for inclusion in design and construction documents. Our regulatory understanding of the affected area’s critical areas and mitigation design helped streamline permit requirements.