Crews working on Sound Transit's East Link extension are preparing to install the project's first rail segment. The 1.3-mile section runs from 80th Avenue Southeast to just east of East Mercer Way and will carry future light-rail vehicles across Mercer Island.
Contractor crews are installing rail on concrete ties set in ballast to form the track bed. A ballast mat, a rubberized material applied to the existing pavement, is installed before crews spread an even layer of ballast along the ground where the tracks will be set.
Prefabricated concrete ties are evenly set on top of the ballast. Once the ties are set, crews thread long sections of steel rail through clips on each end of the ties. The rail bed then sees additional ballast installed to bring it flush with the top of the ties before a tamper then rolls along the rails to perform final adjustments to ensure all components are ready for trains.
Sound Transit says that crews will install rail on the Homer M. Hadley floating bridge, including the innovative track bridges that will accommodate lake motion to allow light rail vehicles to travel safely and reliably across the floating section of I-90, in the coming year.
Construction on the project began in April 2016 and funding for the $3.7 billion project is provided in part by a $1.3 billion Transportation Infrastructure Finance and Innovation Act (TIFIA) loan from the U.S. Department of Transportation.
East Link will extend light rail 14 miles from downtown Seattle to downtown Bellevue and the Overlake area of Redmond via Interstate 90, with 10 stations. Construction of the East Link extension is more than 40-percent complete and the entire line will be operational in 2023.
