Why could the train not have been kept in service during construction work?

Planning has evolved and significant constraints have been identified despite our wish to minimize impacts.

Over the past few months, many meetings between the technical teams of REM, exo and NouvLR (joint venture responsible for engineering and construction) were held to examine issues arising out of maintaining traffic while construction was carried out. It became clear that at a certain point in the progress of the work, the nature of the operations would require complete closure of a section of track in order to guarantee the safety of both passengers and construction workers.