Background
Route 120 is a vital transportation corridor linking Edmundston with the northwestern region of the Province and providing access to Quebec. In late June 2023, Edmundston, NB experienced an extreme rainfall event that caused widespread flooding and infrastructure damage across the city. On Rue Saint-François (Route 120), the existing Arch Structure (Two Mile Brook - Asset T715) became obstructed by flood debris. The blockage and limited hydraulic capacity led to water levels to rise significantly causing embankment failure, and the downstream portion of the structure to collapse causing a complete washout of the downstream embankment.
Emergency measures were taken, including the installation of a temporary modular (Bailey) bridge to restore limited access and subsequent slope and existing Arch structure stabilization to restore unimpeded traffic. Phase 2 requires the existing Arch Structure (Two Mile Brook - Asset T715) replacement to extend the service life of the Route 120 corridor.
The project involves the construction of a temporary on-site detour to allow for an open cut excavation to replace the Arch Structure.
At the completion of the project, the Temporary Detour Road would be removed, and the organic material and landscaping reinstated.
Phases
- On-site detour construction – Summer/Fall 2026
- Traffic shift to detour – Spring 2027
- Excavation of Route 120 and replacement of arch culvert (includes municipal services works) – Summer 2027
- Route 120 reinstatement and traffic shift back to main alignment – Fall 2027
- Detour decommissioning, final cleanup and landscaping – Winter 2027 to Spring 2028