The Kansas City community wanted a landmark bridge to link downtown with the expansive northland. But the Missouri Department of Transportation only had $245 million in its budget for the project, which also included highway improvements. Faced with an unconventional problem, MoDOT took an unconventional approach to deliver the Christopher S. Bond Bridge, named after the state’s senior U.S. senator.
Rather than having contractors bid for the bridge, which spans the Missouri River, MoDOT had them fight for dollars under a fixed budget. And it made the unprecedented move of putting a significant portion of the process in the community’s hands.
Not surprisingly, the biggest challenge was balancing the fixed budget with the community’s desire for a signature bridge. Rather than relying on traditional methods, MoDOT cherry-picked best-value solutions from across the country.
“Who’s to say Missouri’s [solutions] are better than Texas’, or Colorado’s or California’s?” MoDOT project manager Brian Kidwell told Roads & Bridges. “What we wanted was the best of everybody’s packages and we gave them the freedom to do it.”
The deck itself uses precast panels made of high-performance concrete with low chloride permeability to provide extra protection against corrosion. The panels were then post-tensioned, and MoDOT added a 2-in. concrete wearing surface on top.
Builders also utilized 40 cable stays in a semifan arrangement, each with a varying number of strands. The shortest cables have about 39 seven-wire strands, while the longest have more than 100. The cables utilize a triple corrosion-protection system with fully exposed anchors for easy inspection and maintenance. All told, the bridge has roughly 22 million lb of post-tensioning force.
The dimensions added another challenge to the project. The top of the delta-shaped pylon soars 316 ft above the water, with eight drilled shafts extending another 100 ft down. Those shafts include 10.5-ft-diam. rock sockets that go about 25 ft into the bedrock. And the whole project was done under live traffic.
MoDOT figured that beauty is in the eye of the beholder, so the bridge’s aesthetics became the community’s responsibility. The department gave 20 of the possible 100 proposal points to a 12-member Community Advisory Group (CAG), made up of local leaders and stakeholders, which Kidwell said was risky.
“All the way until the award of the contract, we really didn’t know what we were going to get for our $245 million,” Kidwell said. Typically, the community has input, but the DOT has the final say.
But the risks paid off. The community is fully committed to the bridge, and Kidwell said the project should wrap up six months ahead of schedule. What initially seemed to be a huge risk turned out to be one of MoDOT’s smartest decisions. At the time of publication, all northbound—and nearly all southbound—traffic should be freely flowing across the bridge.
Kidwell said, “The risks we took actually made this project into a lot more than we ever thought possible.”