This isn’t the kind of news West Paris commuters were expecting. The Saint-Cloud tunnel, on the A13 motorway, will be closed in the Paris-to-province direction from November 16, 2026 until the end of August 2027, i.e. more than nine months, the Île-de-France regional prefecture announced on Tuesday, July 21, 2026. The closure stretches from the périphérique to the Vaucresson interchange, in the Hauts-de-Seine (92). The province-to-Paris direction, meanwhile, remains open.
The north tube of the structure dates from the 1930s and is showing its age. The latest inspections have uncovered weaknesses that, according to Georges-François Leclerc, the prefect of Île-de-France and Paris, pose no immediate danger but make reinforcement works inevitable within five to ten years.
The schedule has been brought forward for a precise reason: the passage of a tunnel boring machine from the Grand Paris Express under the highway, at tunnel level, for the Line 15 West project, expected in 2027. It would be impossible to carry the machine beneath a century-old structure without first strengthening it.
In concrete terms, the teams will pour a new reinforced concrete hull inside the existing tunnel. A heavy civil engineering operation, preceded by a preparation phase estimated at 35 million euros and funded equally by the Society of Major Projects and the State. It is this technical scale that justifies a continuous closure rather than a staggered, stop-and-go project.
With as many as 80,000 vehicles a day, the A13 ranks among the region's busiest corridors. The prefecture says westbound traffic will be heavily affected and has unveiled two detour routes from the beltway: one via the RD910 then the RN118, the other via the RN13 then the A14.
These routes are likely to fill up fast. The official guidance is to steer clear of the area, favor public transport or carpooling, and push car trips to off-peak hours. To track real-time traffic, Sytadin and Bison Futé remain the go-to resources, with Île-de-France Mobilités helping to plan trains or buses.
A public information campaign will be rolled out at the start of the school year to steer people toward public transport. The prefect has been clear on one point: he does not want the narrow streets of Saint-Cloud, Meudon or Boulogne-Billancourt turned into detour routes. Officials are coordinating with the municipalities and local bus networks to anticipate bottlenecks, and roadworks in the area will be scheduled so they don’t pile up on each other.
The sequence doesn’t end there. To keep the project on track, the A13 will also be closed in both directions in July and August 2027 to carry out maintenance on the Saint-Cloud viaduct. In other words, getaways to the Normandy coast will need to be planned in advance that summer.
The sector had already faced a painful episode in the spring of 2024, when it was suddenly closed for two months after a crack appeared tied to ground movement. This time, the shutdown is planned, giving several months to get ready. All practical information and the decrees will be published on the sites of the Île-de-France prefecture and of the préfecture des Hauts-de-Seine.
Dates and Opening Time
From November 16, 2026 to August 31, 2027
