The Highway 99 tunnel construction project moved into a new direction this week. Northbound.
The upper, southbound deck is almost finished, which clears enough room beneath for assembly to begin for the lower deck that will carry traffic north from Sodo to South Lake Union.
A total 1,152 concrete panels, each as heavy as a transit bus, will be trucked in from Tacoma and fastened atop internal ledges, 7 feet above the bottom of the tube that former tunnel boring machine Bertha left behind.

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