Yellowhead underpass closed after heavy rain fills roadway
City closes stretch of major highway due to water accumulation and risk of hydroplaning in Yellowhead underpass.
The City closed a section of Yellowhead Trail Monday after heavy rainfall filled the underpass below the railway crossing between 121 Street and 124 Street with water, creating a hazard for drivers.
Smaller vehicles risked stalling or hydroplaning in the accumulated water, said Matthew Mohr, parks and roads general supervisor. A road is considered hazardous and closed when water depths risk stalling vehicles or causing them to lose contact with the road—a phenomenon known as hydroplaning.
"Motorists are cautioned that even a few feet of water below road grade can submerge a vehicle and pose a significant drowning risk," Mohr said.
The downpour forced the city to pause multiple summer construction projects. Asphalt and concrete work stopped because water prevents materials from adhering or setting properly. Grading operations on the city's 303 kilometres of unpaved roads also halted, as heavy equipment can damage saturated surfaces.
Road crews instead focused on drainage—clearing debris from catch basins and following up on flooding complaints to check for hidden hazards like sinkholes or open manholes. The city is monitoring for heaving, which can develop if rainfall erodes soil beneath infrastructure.
City officials said the work stoppage was brief enough that no major project setbacks or financial impacts are expected. Contractors continue adjusting work schedules to account for weather conditions.