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Major Construction on Mercer West to Begin: Weekend closure of SR 99 and Mercer Street
The weekend of May 17-20, the Seattle Department of Transportation (SDOT) will begin major construction on Mercer West by preparing to demolish the eastern half of the SR 99 bridge over Mercer Street and widen Mercer Street between Fifth Avenue N and Dexter Avenue N.
When completed, the West Phase of the Mercer Corridor Project will provide a direct connection from I-5 and the new SR 99 Tunnel to Uptown, the Seattle Center, and neighborhoods to the west. In addition to widening … more
Program Spotlight
Launch pit complete, ready for Bertha
Last spring, a field of unturned dirt marked the spot where Bertha will begin digging the two-mile State Route 99 tunnel beneath downtown Seattle. One year and 86,000 cubic yards of soil later, it’s a pit fit for the world’s largest tunneling machine.
Crews finished building Bertha’s 80-foot-deep launch pit on Sunday after nearly a year spent building its underground walls, removing soil and building the infrastructure needed to support the nearly 7,000-ton machine. Its … more