50 Street is a key north/south arterial road in Edmonton that functions as both a major goods movement and commuter corridor. The existing at-grade Canadian Pacifi c Kansas City Limited (CPKC) railway crossing presented a major bottleneck to traffi c movements, with an average of 25 daily back-and-forth train movements resulting in an average delay of 4 minutes (with some delays as long as 15 minutes) for travelers.
The 50 Street widening and grade separation project is constructing two (2) new overpass structures to eliminate the at-grade crossing and widening 50 Street to three (3) travel lanes in each direction within the project limits. Due to the urban location, the project faced several unique challenges including space and land constraints, traffi c management, and numerous existing overhead and underground utilities.
Existing utilities presented a particularly signifi cant risk and challenge to the project, both in terms of schedule and cost. The existing utilities included gas, water, telecommunications, and electricity owned by ten (10) diff erent entities. There were also fi ve (5) oil and gas transmission pipelines and one (1) power transmission line to deal with. The confl icting utilities and two (2) of the transmission facilities needed to be abandoned, removed, and/or relocated while maintaining existing traffi c capacity with two lanes of traffi c in each direction to minimize disruptions.
Several strategies were implemented to mitigate these risks and keep the project on track, including the execution of an “Early Works” Contract where confl icting utilities were addressed prior to the start of main construction of the overpasses. A combination of diff erent construction methods including open trenching as well as trenchless installations (HDD) and targeted traffi c closures and restrictions were utilized to minimize disruptions to traffi c and nearby businesses.
Early and careful planning and utility coordination combined with the successful execution of the Early Works Contract resulted in most of the confl icting existing utilities and two (2) of the confl icting existing transmission facilities being relocated or removed prior to the start of construction of the overpasses, allowing the project to stay on schedule.