USU Utility Tunnel

Contract Amount: $22.5 Million                     Owner: Utah State University                 Completed in 2002 


One of the most unique and challenging projects ever tackled by Whitaker Construction was the $22.5 million USU Utility Tunnel Project.  The project scope included the construction of 6,200-ft of cast-in-place concrete utility tunnels, a new campus steam distribution system, and numerous relocations of existing utilities.  The tunnels typically had 5 to 7-ft of cover with excavation depths ranging from 17-19-ft.  Tunnel excavation and shoring was typically 16-ft wide with wider excavation up to 30-ft required at the tunnel intersections or ‘nodes’.  Inside the tunnel, a new 14” Steam distribution pipeline and 8” condensate return main were constructed with laterals serving each building along the route.  The tunnels have a complete lighting & ventilation system and even a communications system that allows university personnel to use their existing radio system inside the tunnel. There were two main challenges faced on the project. First, constructing this massive project throughout an active university campus with 15,000 students and second, dealing with the relocation or protection of all of the campus utilities that the tunnel crossed.  To deal with these challenges, Whitaker Construction developed an innovative plan to use steel trench boxes coupled together and installed end-to-end for hundreds of feet to protect the workers during tunnel construction.  By using trench boxes in this way, the excavation width was kept to a minimum and it reduced the disturbance to the existing utilities and the campus. Overall the project was a great success, with the university receiving a high quality project in a very short amount of time.