Cass Sobek, Project Manager at Kiewit Infrastructure, won the 2026 Bowen Prize for Great Builders from the Associated General Contractors of America (AGC) in recognition of his leadership overseeing Arkansas’ 30 Crossing project.
“The Bowen Prize recognizes the field leaders who keep complex projects moving, solve problems in real time, and help deliver projects safely and successfully,” said Rick Andritsch, AGC National President and Partner and Vice President of Business Development at VJS Construction Services. “Cass Sobek’s leadership on the 30 Crossing project reflects the kind of innovation, professionalism, and commitment to excellence this award was created to honor.”
According to AGC, the Bowen Prize recognizes the most-accomplished project executives — some of the hardest working but least heralded members of the construction industry.
The Bowen Prize — as well as a Baldwin Group Build America Award for the 30 Crossing project in the Highway and Transportation New ($100 million and more) category — was announced during AGC’s 2026 Annual Conference in Orlando, Florida.
Last year, Kiewit’s Michael Svoboda won the inaugural Bowen Prize for his field leadership during construction of the Broadway Bridge Replacement project in Nashville, Tennessee.
| Your local Trimble Construction Division dealer |
|---|
| SITECH Tri-Rivers |
| SITECH Tri-Rivers |
| SITECH Tri-Rivers |
The Arkansas Department of Transportation’s (ARDOT) $633 million 30 Crossing project in Little Rock improved mobility and safety along four miles of Interstate 30, one of the state’s busiest transportation corridors serving more than 120,000 daily commuters.
Under ARDOT’s first design-build contract, the Kiewit Massman Construction joint venture — comprised of Kiewit of Omaha, Nebraska, and Massman Construction Co. of Overland Park, Kansas — widened I-30, replaced aging bridges over the Arkansas River, and upgraded interchanges in a dense urban corridor.
Construction began in 2020. Under Sobek’s leadership, the project team completed more than 2.3 million work hours while maintaining a strong safety culture. The centerpiece of the project was the reconstruction of the Arkansas River Bridge.
“The demolition of the existing I‑30 bridge [over the river] was particularly challenging because of the structure’s non-redundant design and overall complexity,” Sobek said.
| Your local ASV dealer |
|---|
| CLM Equipment Co |
| CLM Equipment Co |
| CLM Equipment Co |
Originally built in 1958, “The bridge was supported by a two-girder system (10- to 18-foot range in girder depth), meaning the loss of a single primary member could lead to failure,” Sobek said. “That fundamentally changed how we approached demolition — we couldn’t rely on conventional, high-production methods and instead had to treat the structure as a system that needed to remain stable at every step of removal.”
With the new replacement bridge just 10 feet away, “Site constraints and risk exposure were high,” Sobek said. “Even after traffic was shifted to the new structure, we still had to carefully manage work over water, protecting the river from concrete debris with catch barges.”
Changing load paths during demolition also posed a major challenge.
“As we removed the deck and secondary steel, demand on the main girders increased in ways the original design was never intended to accommodate,” Sobek explained. “For example, during deck removal, negative moments increased in certain zones, requiring us to install supplemental bracing just to maintain stability through that phase.”
The team addressed the challenges through a highly engineered and sequenced approach.
“The demolition was broken into precise, step-by-step stages, each supported by detailed structural analysis to ensure the bridge remained stable throughout,” Sobek said. “We also incorporated significant temporary works — including custom designed and fabricated pier brackets, girder bracing, strongbacks, and falsework towers — to provide alternate load paths and maintain structural integrity as key elements were removed.”
In addition, “Rather than taking the structure down in large, uncontrolled sections, we used a combination of single- and double-girder lifts with heavy lift cranes weighing as much as 426,000 pounds, allowing us to remove the bridge in controlled segments,” Sobek said. “Custom lifting systems and engineered connection points were developed to safely handle the weights and geometry of each lift.”
Sobek noted that the complexity of the structure required the team to approach its removal more like deconstruction than traditional demolition.
| Your local Magni dealer |
|---|
| Kirby-Smith Machinery |
| Kirby-Smith Machinery |
| Kirby-Smith Machinery |
“Through detailed planning, temporary works, and disciplined field execution, we were able to safely remove a highly complex, non-redundant bridge while managing risk to workers, the public, and the surrounding environment,” he said.
Beyond the coordination and sequencing required for the bridge demolition, Sobek credited a critical period at the start of the project as key to its overall successful completion.
“The Optimization and Refinement period, developed by ARDOT, is essentially a dedicated phase at the start of the project where the owner and design-builder work together to refine the design to fit within ARDOT’s budget, reduce risk, and improve the overall plan before construction begins,” Sobek said. “For us, that nine-month window was critical — it gave us a nine-month head start on major schedule risks like utilities and right-of-way. We also used that time to build strong relationships and understand ARDOT’s expectations, which really helped carry us through the COVID challenges that followed.”
Sobek also cited leadership alignment between ARDOT and the joint venture team as another important piece in the project’s success.
| Your local Leica Geosystems Inc dealer |
|---|
| Laser Specialist inc |
| Laser Specialist inc |
| Laser Specialist inc |
“The leadership from both sides put the project first in their decision making,” he said. “Both sides were dedicated to delivering a quality product to the people of Arkansas on schedule. Both sides followed through on commitments made — always true to their word. [We] developed a trusting relationship which expedited conflict resolution and led to efficient decision making.”
To support the development of future project leaders like Sobek, the AGC Education and Research Foundation provides $50,000 to a construction education program chosen by the Bowen Prize winner. Sobek selected the Arkansas Construction Education Foundation (ACEF).
“The Arkansas Construction Education Foundation stood out because of its direct impact on the people of Arkansas,” he said. “Through its heavy/civil training facility in the Port of Little Rock, ACEF will support expanded training in welding, ironworking, millwright, concrete finishing, diesel mechanics, and heavy equipment operation. ACEF is providing real opportunities for people and building a stronger local workforce for our industry, which made it an easy pick for the prize.”
Bob Bowen, Founder of Bowen Engineering, who endowed the award, said, “Leaders like Cass Sobek represent the very best of our industry, and I hope their accomplishments inspire the next generation of construction professionals to pursue excellence in the field.”
