The redevelopment project for the RD 57, initiated in 2015, has begun between Moissy, Réau, and the A5-Sénart business park. The goal is to streamline traffic, enhance safety, and promote sustainable mobility through the creation of a greenway.
Starting October 5, 2026, interventions near the roundabout at the entrance of the business park will prepare for utility works, causing occasional traffic disruptions. Subsequently, from October 19 to November 1, the bypass of Réau via Ourdy will be closed for utility works, with a detour in place. These works will continue until December 2026 on the central roundabout.
In parallel, phase 1D of the project is underway on the closed section between the entrance of the village of Réau and the A5b motorway. The detour via interchange n°12 and the RD305 North remains in effect until February 2027.
Phases 1B, 1C, and 1D, which began on August 10, 2026, and are scheduled until February 2027, include connecting traffic from the old RD 57 to the new one, resuming the North access to Réau, and carrying out works on the RD 57 East between the new roundabout and the A5b.
Specific closures are planned: from August 10 to 17, 2026 (phase 1B), the RD 57 will be closed between the A5-Sénart park and the entrance to the village of Réau. From August 18 to September 8, 2026 (phase 1C), the RD 305 South will be closed at the entrance to the village of Réau, and the RD 57 East will be closed from August 18 to February 2027 (phases 1C/D).
A phase of utility works is also scheduled for October/November 2026 near the A5-Sénart park, with a closure of the South Link access during the Toussaint holidays and expected traffic disruptions entering and exiting the park.
The overall project, officially launched on September 26, 2025, includes transforming two intersections into roundabouts, widening the road, and developing a greenway. The road will be configured as 2x2 lanes at roundabout entrances and 2x1 lane on the main sections, with integrated landscaping.
