Design improves traffic flow and increases safety on Highway 779
April 5, 2023
Highway 779 through the Town of Stony Plain, located in the Edmonton Metropolitan Region, was a four-lane, undivided road without access control, which impacted traffic flow and posed safety concerns. Alberta Transportation and Economic Corridors (formerly known as Alberta Transportation) retained Associated Engineering as prime consultant to improve approximately three kilometres of Highway 779 through Stony Plain.
Associated Engineering's scope of work included preliminary and detailed design, tendering, construction supervision, contract administration, and post-construction services to remove uncontrolled accesses and widen the existing roadway to a four-lane, divided cross section with a raised concrete median that accommodates dedicated left-turn lanes at intersections.
In addition, the design included upgrades to the alignment and lane configurations on intersecting roadways to improve capacity, six new traffic signals, changes to residential and commercial accesses, replacement of existing roadway LED lighting, new storm sewers and catch basins (designed to accommodate expected future increase in storm intensity), a storm pond, burial of the existing overhead power lines, paving of back lanes parallel to the highway, and new pedestrian facilities on both sides of the highway.
Utility conflicts were a major challenge on the project, and many utility conflicts could only be identified during construction. These included extremely shallow storm sewers, gas lines, telecommunication lines, a railway crossing widening, and fibre optic lines. In addition, multiple unidentified and abandoned utilities were discovered during construction that were not on the utility locates.
Associated Engineering worked with the contractor to identify the potential conflicts and coordinated with utility companies to mitigate the issues.
βTo overcome the shallow utility lines, we redesigned the road structure to limit our excavation depth and made alignment changes to the storm sewer. The contractor, Wells Construction (a Division of Lafarge Canada), used different construction techniques and hand-located utilities in certain areas, which allowed the utility owners to reduce the required cover over or clearance to some utilities during construction.β - Project Manager, Warren McKay
Where minor utility relocations were required, the grading sub-contractor contracted directly with the utility company to relocate the facility, which helped keep construction on schedule. When required, Alberta Transportation and Economic Corridors assisted to coordinate scheduling with the utility companies to meet project milestones. This partnering approach helped to reduce potential delays and costs associated with utility conflicts and relocations.
As a result of our successful collaboration, the team, including the project owner, lead consultant, and contractor, were recognized with an Alberta Transportation Partnering Award in the major project category for the Highway 779 project in 2022.