BF76979 Double Barrell Culverts

About This Project

The culvert carrying Gros Ventre Creek along Highway 514, approximately 8 km northwest of Elkwater, Alberta, had reached the end of its service life. Originally constructed in 1969, the arch culvert had developed excessive roof sag, warranting a full replacement.

ISL served as prime consultant, delivering preliminary and detailed design, tender preparation, construction supervision, contract administration and post-construction services.

The replacement structure consists of two 1.4 m diameter corrugated steel pipe (CSP) culverts, each 27.0 m in invert length, installed on a two-degree left-hand forward skew to the highway alignment. 

Two key challenges shaped the project’s approach. Highway 514 required continuous public access throughout construction, leaving limited room for a conventional detour within the existing right-of-way. ISL’s solution was a staged open-cut installation method, keeping one lane open at all times under alternating-direction signalized control. ISL coordinated closely with the client throughout, ensuring the contractor’s traffic signalization operated efficiently and provisions in the tender documents supported the staged approach. Winter construction conditions added a further constraint — driven by permit deadline requirements — which ISL addressed by expediting the detailed design and tender closure, and requesting the contractor to account for cold weather construction in their submittals.