Project Title & Location
SR 16 / I-5 - Westbound Nalley Valley, Tacoma.

Project Description
This project is the first of three projects to rebuild the I-5/SR 16 Nalley Valley interchange in Tacoma. The existing bridges are too narrow to carry additional lanes and the unique structure-type prevents widening. This project improves safety and increases mobility by eliminating traffic weave, adding new lanes and building dedicated ramps to Sprague Avenue. Work includes building a new westbound viaduct, new ramps between SR 16 and Sprague Avenue and new ramps from I-5 to WB SR 16.

Contractor/Consultant
Project not yet advertised or awarded.

Recent Progress

Design: The project team will submit a 60% design review mid-September. 

Construction: The project is on track for construction bidding in March 2008.

Design Construction Impacts

Environmental Impacts / Compliance

NEPA re-evaluation - Assessing potential mitigations sites for 0.1 AC of wetland impact; Nalley Valley Viaduct has been identified as a possible candidate for the Register of Historic Bridges, may need to do a supplement to the Environmental Assessment; Air and Noise analysis is being re-analyzed for 2030 traffic numbers.  

Impacts to Traffic
Long-term closure of Sprague Avenue, short-term closures of southbound  I-5 to 38th Street off-ramp and 38th Street to westbound SR  16 on-ramp. There will also be night-time closures on I-5, Center Street and South Tacoma Way for girder placement and other construction work.

Planned vs. Actual Expenditures
(Total Project Cost)

Nickel funds included in above costs

2005 Transportation Partnership Account