The I-35W underground stormwater storage facility (SSF), a first-of-its-kind underground solution to interstate flooding, has been selected as a national Public Works Project of the Year.
Awarded by the American Public Works Association (APWA), this honor for the top project in the $25 million to $75 million category is shared with the Minnesota Department of Transportation (MnDOT), which commissioned and facilitated the project, the Barr-led design team that included TKDA and Brierley Associates, and contractor joint venture Kraemer North America and Nicholson Construction (KNJV).
The massive underground SSF is designed to reduce the depth, duration, and frequency of flooding along I-35W at 42nd Street, a major interstate in Minneapolis. Over the past several decades, intense storm events have caused significant flooding, including stormwater geyser events, that posed public safety risks and disrupted traffic and commerce.
Barr led the design team to develop the innovative solution in the face of several critical challenges, including complex hydraulic conditions, deep excavation with a high groundwater table, and adjacent highway reconstruction—all in a restricted space wedged between the interstate and a residential area. The completed facility features six underground storage cells that are each 82–84 feet deep and together have the capacity to hold 4.5 million gallons of stormwater.
“Working collaboratively with MnDOT, Barr and all project partners (KNJV, TKDA, and Brierley Associates) successfully applied the construction manager/general contractor (CM/GC) delivery method for this extraordinary project,” said Mike Haggerty, vice president and senior geotechnical engineer at Barr. “This approach engaged a construction manager during the design process, fostering teamwork and innovation at every stage. We’re thrilled with the outcome we achieved together: positioning the community for improved safety and resiliency in the face of extreme weather events.”
APWA’s Public Works Project of the Year recognizes excellence in the management, administration, and implementation of public works projects, focusing on the alliance among the managing agency, the consultant/architect/engineer, and the contractor as they work together to complete public works projects.