Modernising the Rhône’s locks with no interruption to river traffic
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How can key infrastructure be modernised without interrupting service? Construction work began in 2026 on new upstream gates for two locks on the Rhône, both of which date from the 1950s. VINCI Energies is playing a key role in this colossal project from the Compagnie nationale du Rhône, which must not adversely affect the increasingly busy river traffic. VINCI’s involvement is an exercise in organisational and operational agility.
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This massive project to create two new upstream gates for the Bollène (Vaucluse department) and Châteauneuf-du-Rhône (Drôme) locks on the Rhône will take five years. These historical structures built in the 1950s complete more than 80,000 lockages a year and now require modernisation to ensure their availability 24 hours a day and accommodate traffic increases on this important river route. In 2025, 3.65 million tonnes of goods were transported along the Rhône, representing an 8.7% increase.
Straightforward gate replacements would have required a two or three-month interruption to traffic, contrary to the Compagnie nationale du Rhône’s (CNR) service continuity obligations under the concession contract it renewed for another 19 years (until 2041) back in 2022. The decision was therefore made to build two additional metal gates, each 20 metres high and weighing 200 tonnes. The project also includes the comprehensive renovation of all lockstation electrical and command-and-control installations and the creation of a new electrical room in Châteauneuf‑du‑Rhône.
“This requires preparation far in advance and close coordination between the civil, mechanical and electrical engineering companies.”
The contract to double up the gates was won by a consortium led by VINCI Construction and including VINCI Energies and Baudin Châteauneuf (for the mechanical engineering batch). In terms of electrical engineering and automation, local company Actemium Bourgoin (VINCI Energies), a longstanding partner to CNR, is responsible for integrating the new equipment with the lockstation command-and-control systems.
“This is the largest river construction project CNR has undertaken since the Rhône concession was extended,” says Franck Davoine, Business Unit Manager at Actemium Bourgoin. “From our perspective, this is a flagship project worth €13 million.”
Coordinating operations within extremely tight timeframes
The complexity of a project like this lies in orchestrating major operations without hampering river traffic. A significant proportion of the works will be undertaken with the locks in operation.
The switchovers, connections and reconfigurations requiring an interruption to traffic will be concentrated into planned navigation stoppages, at night or during the annual shutdown in March.
During these navigation stoppages, it will be necessary to coordinate daytime and nighttime operations involving a number of different civil, mechanical and electrical engineering providers. These phases, concentrated into extremely tight timeframes, will require significant human and material resources, with the added challenges of managing concurrent working and personnel safety.
The works will continue throughout the normal lock operating periods, stage by stage, until 2031. “Our challenge is to complete the maximum number of operations without interrupting traffic,” explains Franck Davoine, “from preparing the respective command-and-control architecture to fabrication, pre-assembly and workshop testing. Our stoppage windows are therefore reserved solely for switchovers, connections and testing that cannot be done while the locks are in operation. This requires preparation far in advance and close coordination between the civil, mechanical and electrical engineering companies.”
In summary:
- Modernising the Rhône without interrupting traffic: the Compagnie nationale du Rhône is modernising two historical locks to support the increase in river traffic while ensuring service continuity.
- A colossal industrial project: the project involves the construction of two new 20-metre, 200-tonne lock gates, plus the modernisation of mechanical, electrical and command-and-control systems.
- Actemium, the VINCI Energies industrial brand, in the front line: Actemium Bourgoin is managing the integration of new equipment and the renovation of electrical installations for this strategic project.
- Coordination prowess: intensive concurrent working between many different trades requires meticulous operational coordination, especially during navigation stoppages.
11/10/2026
