Digging Deeper: Tacoma’s I-5 Rebuild Reaches Last Stretch
Nearly 20 years into a $1.4-billion megaproject to widen and realign Interstate 5 through Tacoma, the state’s third-largest city, the Washington State Dept. of Transportation has reached one of the final stages—the $324-million I-5 Portland Avenue to Port of Tacoma Road Southbound HOV project. This phase includes 1.8 miles of interstate work and a nine-span replacement bridge on the southbound side. The bridge includes a 223-ft-long girder, the longest prestressed concrete girder in the U.S.
The project is part of WSDOT’s larger I-5 SR 16 Tacoma-Pierce County HOV program, started in 2001. It marks the last fully funded phase that completes Tacoma’s updated HOV system from I-5 to SR 16. The project is led by Guy F. Atkinson Construction, a subsidiary of Clark Construction, working with Jacobs. The design eliminates a bottleneck-inducing curve on the I-5 by replacing the existing southbound bridge over the Puyallup River with a new, wider version without a curve. That required going over both the river and an adjacent railyard used by BNSF Railway Co., the Union Pacific Railroad and Tacoma Rail. The design also removes piers from the river, which required the work to “stretch the girders out as far as possible,” says Jay Teskey, Atkinson’s senior construction manager.