When Does The Temporary Nalley Valley Viaduct Open?

Out with the old and in with the temporarily new – that’s what is in store for the more than 102,000 motorists who travel State Route 16 through the Nalley Valley in Tacoma. 

If crews have enough dry weather to complete preparatory work, including weather-dependent roadway striping, eastbound SR 16 traffic could be shifted onto a newly-built temporary eastbound bridge as soon as this Thursday night.

To prepare for the traffic shift, crews will close eastbound SR 16 at Union Avenue during night hours. If weather cooperates, those closures are scheduled as listed below. In the event of inclement weather, some of the night closures and the traffic shift may be delayed. 

• Wednesday and Thursday, Dec. 12 and 13: All eastbound SR 16 lanes will close from 11 p.m. until 4 a.m. the following morning. Eastbound SR 16 traffic will be diverted onto the Union Avenue exit. 

• Saturday, Dec. 15: All eastbound SR 16 lanes will close from 12:30 a.m. to 6 a.m., again using the Union Avenue exit. 

Once the traffic shift is completed, motorists will drive on a new 1,350-foot-long section of roadway that sits between the westbound SR 16 structure and the existing eastbound viaduct.

As planned, 650 feet of the new structure is temporary and will be demolished during a future stage of the project. The remaining 700 feet of the structure are permanent and will be used for the future HOV connector project scheduled to begin in 2020. 

“Shifting traffic onto the temporary structure is a huge milestone on this project,” said Neal Uhlmeyer, project engineer. “That shift will allow our contractor, Mowat Construction, to demolish the old eastbound structure, making way for the final eastbound bridge to be built.” 

The $115 million I-5/SR 16 Eastbound Nalley Valley is part of WSDOT’s Tacoma/Pierce County HOV program, ultimately adding 70 HOV lane miles on state highways in Pierce County. The project replaces the existing eastbound SR 16 structure that spans Nalley Valley and completes the SR 16/Sprague Avenue interchange. The first portion of the interchange overhaul, the westbound Nalley Valley viaduct, opened June 2011.

Press release by the Washington State Department of Transportation.