Suburban trains #1: the return of the magic wand?

It was an announcement that surprised and delighted and reopened a long-standing debate: on 22 November, the French president called for a “great national ambition” that should lead to the development of an RER-type service in 10 French cities based on the existing rail networks. A few days earlier, 15 regional presidents launched an appeal for a “new rail deal”, also seen as a response to the challenges of climate change.

But if the question of the development of these suburban trains is generating renewed media interest, it is far from being the first time it has been discussed. Indeed, the idea of maximizing the potential of these networks has been regularly raised for several decades in an attempt to respond to a range of issues, even if it means making it a quasi-miraculous solution.

What needs can these services really meet? What prospects do they open up for the territories? What are the obstacles to their development? Our experts take a look at the issue.

Suburban trains: a widely shared rationale

Decarbonizing mobility is a crucial issue for ecological transition, especially with the renewal of France’s climate commitments at the end of COP27 in Sharm el-Sheikh.

The ambition is not new; its latest concretization dates back just three years with the promulgation of the Mobility Orientation Law (LOM) and its multi-year budget of 17 billion euros, half of which was earmarked for rail. In the wake of this legislation, which gives legal existence to Metropolitan Express Services (SEM), an SNCF Réseau master plan identified some thirty eligible cities in 2020.

But why focus on railway networks and the development of suburban services?

The justification for developing these services is clear and generally shared:

  • On the one hand, to rely on the structuring effect of the train on regional planning to try to channel urban development around stations and stops;
  • On the other hand, to offer a credible alternative to the solo car to suburbanites in order to decarbonize daily mobility;
  • And finally, to provide a social solution in the face of rising fuel prices and traffic and parking restrictions in low emission zones for the most polluting vehicles (gradual implementation until 2025).

30 years of debate: suburban trains facing the complexity of rail arbitration

If everyone agrees, then why have commuter trains not been deployed more quickly in France?

There is no shortage of challenges in implementing them:

  • Firstly, it is often forgotten that the development of rail infrastructure and services, however structuring they may be, are also long-term projects and require significant investment;
  • Secondly, in the face of the complexity of the system, we sometimes forget certain initial trade-offs that have ended up shaping current service policies. Hence the importance of reopening the debate and building a new railway consensus.

To understand this point, it is necessary to go back to the question of the use of rail infrastructures in France. We must remember that the existing railway networks are currently used for many services and that the cohabitation between these different uses is complex: high speed, intercity, regional express trains, freight, work and maintenance periods, etc.

Competition between services according to political agendas and complicated alignment

Understanding the issues related to mixed traffic and its management constraints is a key issue in addressing the subject.

The capacity of the railway infrastructure is measured in train paths and depends on several factors, such as the number of tracks, the type of signals, the number of blocks, etc. In addition, the speed difference between trains is a key variable. In fact, the capacity of the infrastructure is optimal when all trains run at the same speed and make the same stops.

To explain this key yet complex point, it is necessary to understand that in the case of cohabitation of fast and slower trains, it is necessary to increase the spacing between trains for safety reasons, particularly in relation to the risk of trains catching up and colliding. In order to increase capacity, it is then possible to either slow down fast trains or increase the speed of slower trains (eliminating stops, etc.).

The challenge posed by the suburban trains is therefore considerable and reinforces past debates on the balance of train path allocation between fast services (TGV, Intercity), local services, freight services, night trains and the necessary maintenance operations and work on technical installations.

Taking a step back, it can be said that the current logic for allocating train paths prioritises services that allow the infrastructure to be used at its optimum capacity, i.e. the fastest services.

From then on, suburban trains will add a further layer of complexity to these architectures, reactivating the trade-offs at constant infrastructure level between fast services from one metropolis to another, fine services to regional areas and intra-metropolitan issues. The regions and metropolises have objectives that may be divergent: while the regions and metropolises agree on a fast service to the capital, the regions are concerned with regional territorial equity, while the metropolises are looking for a quarter-hourly service to their conurbation.

To get out of the rut, and to imagine fine metropolitan quarter-hourly services, the entire rail system must be reexamined and remodelled (at the level of hubs, stations – train capacity, bypasses), in the current section (partial track doubling, dynamic bypasses, etc.) and, at the same time, by facing other complex issues such as the availability of land in dense areas, or the budgetary constraints of local authorities…

The need for a new rail deal

Faced with the scale of the technical and organizational challenge and the level of investment required, procrastination has often been the order of the day.

But President Macron’s announcement rekindles hopes of support commensurate with the challenge and also makes it possible to set in motion organisational and technical adjustments based on a clarified long-term vision, gradually removing the obstacles.

Existing technical levers

For example, track plans and capacity can be optimized by allowing two trains to be parked on the same track. It is also possible to optimize and modernize systems and signalling, or to add switches to increase the capacity of lines.

On a metropolitan scale, the transport network can also benefit secondary stations to relieve the central station and connect the network to mass transit systems such as metro. Investment in high-speed lines also restores capacity on historic routes, allowing priority orders to be rearranged on the various lines.

Financial and governance schemes that need to be adapted

The first rough observation to be made is that a quarter-hourly metropolitan service represents an overall investment of one billion euros. Here again, adjustments are possible: for its new European Metropolitan Express Network, Strasbourg has chosen to stagger its ramp-up, with a quarter-hourly service at peak times provided by 800 additional trains in 13 stations from the launch in December 2022, and a target of 1,000 trains by the summer of 2023. At the helm: a joint metropolitan-regional syndicate to share the operating costs, notably through multi-year financing agreements.

The establishment of suburban trains services raises a crucial question of governance: the regions, which are responsible for rail, and the metropolises have often remained in their own way until now. The regions, by promoting regional territorial equity, and the metropolises, by pushing the need for metropolitan services without financial compensation, since they do not have rail competence.

This logical framework is in line with the distribution of competences foreseen by the legislator. But as we have understood, to go further, it is a new logic of cooperation that seems to have to be installed in the metropolis/regions couple, notably for the financing of the operation of suburban train services.

In addition, many financial avenues remain to be explored, such as the development of land around stations, or the interfacing of fare policies at the territorial level. However, there is no single solution; solutions must be found in each metropolis.

no “magic” answer

If the ambition is welcome but the concretization is still vague, the metropolitan trains have the merit of re-launching the debate around central questions for sustainable mobility, the ecological transition of the territories, and the future of our railway network.

The fact that suburban trains services have survived for decades while maintaining their relevance is proof of their adaptability to complex and evolving issues. But we must be careful not to make them a “magic” answer. The reflection on their appropriateness must, in cascade, lead to a wider work on intermodality, urban sprawl, preservation of natural spaces, quality of life, evolution of work and consumption patterns…

These are issues that reshuffle the deck and that cannot be resolved by a suburban train alone! In any case, an impetus from above will not be useless in clarifying priorities: regions and cities alike are now waiting for the financial commitments that the State must present at the beginning of 2023 in order to make the announcements made by Emmanuel Macron a reality.

Coming soon: an Expert’s Insight on suburban trains from India, the US and Asia.

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