In Rouen, the Guillaume bridge was repaired while traffic was flowing after a barge collided with it.
Cerema revisits the methods used to diagnose and repair the Guillaume-le-Conquérant bridge in Rouen, following the collision with a barge crane in December 2023. Presented at the Engineering Structures Conference on June 9, 2026, this feedback is technical in nature: it does not represent a new decision or the announcement of any construction work. For users, the main change has already occurred with the complete reopening of the bridge in November 2025.
An accident, then a targeted diagnosis
On December 24, 2023, the crane arm of a barge struck a beam in the central span of the bridge, damaging its weld over several meters. The structure, which opened in 1967, spans the Seine in Rouen. It carries road traffic, accommodates a high-capacity bus service, and allows the passage of oversized loads.
The Cerema presentation details, in particular, the use of photogrammetry to estimate the length of the damaged area. This technique makes it possible to produce meaments from images. The diagnosis then guided the repair of the affected beam.
The construction site was organized to minimize disruption.
According to Cerema, the repairs were scheduled in phases to allow work to continue while traffic was flowing, with limited impact on bridge operations. The navigation clearance under the structure was also maintained throughout the work. Cerema describes the technical choices made here; it does not provide a cost estimate for the project in this presentation.
The Rouen Normandy Metropolitan Area led the rehabilitation project, which began in the summer of 2025. During this period, restrictions affected one traffic lane and pedestrian, cyclist, and disabled access routes. The City of Rouen announced the bridge’s full reopening on November 14, 2025, ten days ahead of schedule.
What this changes today
For motorists, bus passengers, and other people crossing the Seine, this feedback concerns an incident whose main traffic disruptions have been resolved. It also highlights a concrete infrastructure management challenge: accurately assessing the extent of damage before determining repairs, while maintaining road and river traffic as much as possible.
The presentation was given at the Structural Engineering Conference, jointly organized by Cerema and Gustave Eiffel University on June 9, 2026, in Champs-sur-Marne. The event is aimed at professionals working on civil engineering structures; no new interventions on the Guillaume-le-Conquérant bridge are announced in this feedback report.
Main source: Cerema – News (www.cerema.fr)
Original article: See the original source
Author: Cerema
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