35W Minnesota River Bridge Design-Build
Burnsville and Bloomington, Minnesota
Award of Merit
OWNER: MnDOT
LEAD DESIGN FIRM: Parsons Engineering
CONTRACTOR: Ames Construction
CIVIL ENGINEER: Alliant Engineering
STRUCTURAL ENGINEER: Parsons Engineering
The 60-year-old bridge spanning the Minnesota River has been replaced with a twin-structure crossing that provides long-needed added traffic capacity while also eliminating flooding issues at the approaches. Crews worked through bitter winter weather in order to complete initial work in 2019, but significantly high spring and early summer floods complicated marine-based foundation work for the four river piers. Additional access roads and equipment pads were installed to keep work going during minor flood events.
Photos courtesy of Ames Construction
Standard infrastructure safety practices were augmented with special measures, such as scheduling work within cofferdams to avoid high-water season and conducting periodic maintenance-of-traffic meetings and onsite walkthroughs with local police and first responders to review access rescue procedures. Installation of wick drains and synchronized sitework on the north embankment prevented a repeat of a substantial slope failure that occurred during the original bridge’s construction. Approximately 300,000 staff hours were recorded during the 28-month project with no recordable incidents or lost-time injuries.