35th and O street Roundabout

The 35th and O Street 4-legged roundabout project consisted of several challenges during the building operations. Some of these challenges included diverting irrigation run-off water around the site, large utility relocates and a tight 45-day schedule to complete all of the PCCP & HMA paving. The timeline of the project was the largest challenge. Every step of the operation had multiple other operations needing to follow. Any delays would disrupt the entire project, so making sure all of the work was in place and ready for the 45-day closure was crucial to successfully meet the schedule. IHC Scott’s superintendent, Tyson Kincaid, and Pipe Foreman, Jaime Roehrich, put their years of experience and creative problem-solving abilities together and resulted in a solution to route the farmer’s run-off water under the job and around the job unitizing a temporary water line. In doing this, it allowed the project to continue moving and IHC Scott was able to complete the earthwork and begin the pipe installation operations. The pipe installation process drove a huge milestone in the project. Upon completion of the pipe, the intersection closure started. Once the closure began, the first order of business was to have the City of Greeley reroute a water line.

The original schedule was delayed by over a month while the water line was relocated through one of the largest legs of the roundabout. This put a strain on the original schedule so IHC Scott had to make adjustments in their earthwork, pipe, base and paving operations to adapt to the circumstances and still finish all work in the 45-day allotment. Upon starting paving, everyone was aware of the amount of handwork required in multiple locations of the project. However, IHC Scott’s Paving Foreman tried something not seen in the paving industry before. All 3 circles of the roundabout, with very sharp diameters, were paved with a slip form paver. This accomplishment would not have been possible without the hard work, team attitude, and, of course, quality concrete produced by every crew member involved. It is safe to say, IHC Scott ended this job with a very proud owner and proved that IHC Scott holds true to the saying “Our Word is Our Bond.” 

The most unique part of this project revolved around the project’s geometry. This being a heavily used intersection in the area, we were required to maintain traffic through the intersection for the majority of the project duration.  A 45-day full intersection closure was allowed for the completion of the intersection itself.  Because the roundabout geometry shifted the intersection to the North, we were able to complete approx. 65% of the required dirt and pipe work prior to the full intersection closure, but little of the paving.  Due to the limited time allowed to complete the intersection under closure, it was imperative that as much of the paving as possible be completed with a slipform paver.  Utility relocation delays outside of our control further compressed the schedule.  The project team worked together to develop a stringless model and modified our G&Z S600 paver to allow for slipform paving of the three inner circle lanes of the roundabout, something the manufacturer of the paver had previously told us was impossible with the paver that was utilized. This innovation on the part of the project team resulted in a 2-week pick-up in the project schedule that offset most of the previously mentioned utility relocation delay, allowing us to open the intersection ahead of the allotted closure duration.