I-5 – SR 526 to US 2 HOV Lanes
Improved traffic choke points and created safer roadways for I-5 drivers
Washington State Department of Transportation
Roadways & Bridges
The $221 million, design-build I-5 Everett HOV Project added over 10 miles of HOV lanes and merge lanes through the congested urban corridor. In addition, the scope of work included widening 18 bridges, constructing or replacing five bridges, a new Single Point Urban Interchange, improved freeway exits and on-ramps, and the construction of 4.25 miles of noise walls, as well as 11 water quality facilities to hold and filter stormwater. The project required complicated traffic control and staging plans, and subcontractor coordination for earthwork, drainage, paving, and electrical and intelligent transportation system implementation.
The SPUI was added post-contract. The interchange, where entrance and exit ramps converge at a single location is controlled by traffic signals in the center. The SPUI maximizes traffic flow while reducing the necessary right-of-way. This interchange was negotiated, designed, and constructed within one year, and stayed within the accelerated delivery schedule. The two-span bridge structure consisted of 50 pre-cast concrete girders.
The new 1,350-foot Broadway flyover bridge that eliminated a notorious I-5 choke point, was delivered just 13 months after notice to proceed. Work also included two, eight-span I-5 mainline bridge expansions over the BNSF Railroad.
Adjacent to 25 wetlands and the Snohomish River, the project required environmental compliance in stormwater management, archaeological resource management, wetland avoidance and mitigation, and regulatory agency coordination, being one of the few projects in state history that the contractor obtained the NPDES permitting. The team created a park-like 13-acre water quality treatment site with eleven water quality facilities, an aqueduct bridge that conveyed stormwater over the BNSF railway, and a waterfall that connects to the city of Everett’s riverfront trail system.
Atkinson was an excellent project partner using innovative construction methods to limit impacts to the public and deliver the work. Atkinson’s project managers deserve a great deal of credit for their planning, scheduling, and coordination of this work with their subcontractors, fabricators, suppliers, WSDOT, and the City of Bellevue to deliver this project.
Dave Becher, Engineering Manager, WSDOT