A 4 closed for 5 days in Seine-et-Marne

TheA4 will undergo a new series of night-time closures in Seine-et-Marne from Monday August 18 to Friday August 22, 2025. After the interruptions in July, the freeway closes again between Bussy-Saint-Georges and Ferrières-en-Brie to allow work on the new Sycomore interchange to progress. This week of disruptions is part of the summer strategy adopted by freeway operators, who are taking advantage of the drop in traffic to carry out their major infrastructure projects, such as the many works that will affect the entire Paris region network this summer.

Since October 2024, work on the new Sycomore interchange has been transforming the motorway area between these two towns in the Seine-et-Marn region. This major infrastructure, managed by SANEF (Société des autoroutes du nord et de l'est de la France), will connect the Avenue Gutenberg with the future Rucherie development zone in Bussy-Saint-Georges. The summer of 2025 is a strategic period for the progress of this major project.

The closures mainly affect night-time traffic. From Monday August 18 to Friday August 22, the freeway will be closed to Reims-bound traffic from 10.30pm to 5am. Motorists will have to exit at theA4/A104 interchange. At the same time, the A104 and Ferrières-en-Brie entry ramps (exit n°12) will also be inaccessible from 9.30pm to 5am.

These restrictions are due to theinstallation of new temporary signage, essential for the smooth running of operations. SANEF's priority remains the safety of drivers and site crews, while keeping traffic flowing as smoothly as possible during rush hours. For several months now, users of the A4 have been using the yellow signs to guide traffic through the work zone, as confirmed by information issued by the Bussy-Saint-Georges town hall.

The Sycomore interchange project is much more than just a road development. This infrastructure is a prerequisite for the development of the new ZAC de la Rucherie in Bussy-Saint-Georges. The aim is to create direct access from the freeway to this future residential and commercial district, thus avoiding saturation of the existing interchange. The mayor of Bussy-Saint-Georges had set this condition with the French government before authorizing the urban development.

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The installation of this new interchange is accompanied by significantenvironmental improvements. The works will bring the road back up to modern drainage standards and include the creation of new lanes to improve traffic flow. These developments bear witness to the changing requirements of motorway infrastructure, now integrating environmental and sustainable mobility issues.

For motorists accustomed to using this route, several alternatives are available during these night-time closures. The main detour is via the A4/A104 interchange, enabling drivers to bypass the work zone. Drivers can also consider other routes within the Paris region, depending on their final destination, by consulting Sytadin 's recommendations for real-time traffic conditions. For journeys to the east of Paris, it is advisable to consult the latest traffic information, which lists all summertime disruptions.

This period of summer work is part of a wider drive to modernize the Paris region's infrastructure. As with public transport, summer is a window of opportunity to carry out large-scale works with minimal impact on daily traffic. The Direction des Routes d'Île-de-France (DiRIF) coordinates these operations to optimize maintenance and modernization of the regional road network.

Completion of theSycomore interchange is scheduled for 2025, marking a major milestone in the development of the Seine-et-Marne region. The project, costing a total of 30 million euros, is being financed by the ÉpaMarne public development body to the tune of 11.7 million euros. Once completed, this new access will considerably facilitate travel between the freeway and the new development districts.

To follow the progress of these works and anticipate future closures, motorists can consult the latest information on the official SANEF and DiRIF websites, as well as on the real-time traffic applications that list all disruptions on the Paris region network. We also advise you to follow the summer traffic news to anticipate your travels in the Paris region.