This $187 million bridge replacement was the largest and final project of the OTIA III State Bridge Delivery Program. Over 10 years, the program allocated $1.3 billion to repair and replace hundreds of aging highway bridges throughout Oregon. It is the largest bridge replacement project ODOT has ever taken on.
The original Willamette River Bridge, which carried an average daily traffic count of more than 70,000, developed shear cracks severe enough to shift from the truck traffic live load.
OBEC is the principal designer for demolition of the existing bridge, construction of two new parallel bridges, and reconstruction of the roadway approaches.
CM/GC Contracting: This was ODOT's first use of Construction Manager/General Contractor (CM/GC) contracting which allowed the costly, protracted construction issues to be eliminated by the immediate resolution of questions raised by field staff during the design phase of the project.
Staging and Mobility: The requirement to stay within the existing right-of-way resulted in the reconstruction of the I-5 freeway and connector ramps within their current footprints. This required complicated construction sequencing, resulting in nine traffic control stages which OBEC roadway engineers modeled in 3-D. These models accurately reflected the precise size, location, and elevation of each temporary and permanent construction feature to resolve all potential construction conflicts before they could lead to construction delays in the field. Construction has progressed with no conflicts or modeling busts.
Arts Collaboration: Heavily used walking and cycling trails and public spaces exist underneath both bridge ends. A design charrette involving local architects, artists, and landscape architects worked with members of OBEC's design team to brainstorm potential aesthetic enhancements.
A Design Enhancement Panel (DEP) comprised volunteer participants from the charrettes as well as members of a Citizen Advisory Group to oversee the development of the final aesthetic enhancements. The DEP worked with OBEC staff to develop a formal qualification-based Request for Services to select three local Art & Design Teams (ADTs) to design aesthetic enhancements for three distinct project zones.
Watch time-lapse photography of the bridge construction:
Additional videos from ODOT and Slayden Construction: