Highlights 2023

KEy figures

In 2023, LISEA achieved major milestones in its development. A commercial milestone, with more than 100 million passengers since the line was opened, of which 21 million in 2023. Major milestones in the development of our Stabling and Maintenance Facility at Marcheprime, with the acquisition of the land and the submission of applications for administrative authorisations. An operational excellence milestone, with a regularity rate of 97.6% and contractual indicators in the green. Lastly, it was a year in which we reaffirmed our commitment to CSR, with €800,000 allocated by the SEA Fund for Territorial Transition to projects promoting local, sustainable agriculture. Our aim is to continue these efforts and to encourage the emergence of new rail transport services to meet the public’s growing demand for low-carbon mobility, while supporting the regions crossed by the SEA HSL in forwarding their environmental approach and boosting their attractiveness.

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Facilitating the opening up to competition to develop rail services

At a time when rail has been identified as one of the main levers in favour of the ecological transition, opening up to competition appears to be one of the essential conditions for increasing rail services and thus meeting the challenges of climate change, growing passenger demand and the social and economic development of the regions. In practice, however, competition remains very limited.

SMF: towards the completion of the project

A concrete solution to the opening up to competition, the Stabling and Maintenance Facility (SMF) for high-speed trains at Marcheprime (Gironde), supported by LISEA since 2018, made major progress in 2023. June saw the signing of the deed of sale for the land, the submission of the Planning Permission and Environmental Consent applications, and the launch of a major consultation campaign with local residents from September to November 2023.

Lifting one of the barriers to entry for new operators

Access to rolling stock maintenance and stabling facilities is one of the main barriers to entry for new operators, as the maintenance centres are located in the Ile-de-France region and in Lyon and are managed by SNCF Voyageurs. The creation of an independent SMF in the Bordeaux area is therefore one of the conditions for the successful arrival of new railway companies and the development of rail services in south-west France.


2023: Rail traffic on the rise


With 21 million travellers and the 100 million mark passed since the line entered service, the increase in traffic on the SEA is one of the highlights of 2023. The reason for this is the growing attractiveness of the SEA HSL and the areas it serves, the rising popularity of rail travel among passengers and the strengthening of the commercial offer, reflected in particular in the replacement of several single units by multiple units. That said, the service on the line is still insufficient to meet this demand and needs to be strengthened, thanks both to the sustained efforts made by the incumbent operator and to the prospect of the arrival of new operators on the line.


To safety and performance

Performance indicators in the green

The SEA HSL performance indicators (regularity, availability, reliability and comfort of the infrastructure) defined in the LISEA concession contract are essential tools for assessing, monitoring and improving the quality and efficiency of the line. In 2023, all these indicators were in the green, even surpassing contractual requirements.

Resilience of the SEA HSL – anticipating the impact of climatic hazards

In 2021-2022, LISEA carried out phase 1 of the resilience study for the SEA HSL, formalised by the Résalliance engineering office and CEREMA. This study consists of an exhaustive diagnosis of the SEA HSL’s vulnerability to climatic hazards likely to occur in the coming years: drought, heat, floods, winds/storms, earth movements.

In order to continue and expand on this study, the phase 2 project was initiated in 2023, with the launch of the study scheduled for 2024.

SEA HSL/TGV M: innovation meets performance

In the 4th half of 2023, the dynamic pre-validation tests for SNCF Voyageurs’ future TGV M (InOUI 2025) were run on the SEA HSL. These trials were used to test the rolling stock and safety equipment. With 20% more carrying capacity than the current double-decker TGV Duplex, 115 trainsets will gradually be added to the SNCF’s TGV fleet, with the first commercial service scheduled for 2025.






Inauguration of the Hôpital des Champs footbridge

On 4 October, LISEA, together with the President of Greater Poitiers, representatives of Poitiers Town Hall, the Vienne Prefecture, the Nouvelle-Aquitaine Region and the Regional Director of EDF (co-sponsor), inaugurated the Hôpital des Champs footbridge in Poitiers, which has been converted into a cycle path. This development is part of a wider mobility project to create a cycle path linking Poitiers city centre station to the Futuroscope station. A response to the challenges of decarbonising current forms of mobility, this project also provides a solution to the problem of “first and last kilometre” commuting (the journey to and from the station), which is still often made using modes of transport that emit high levels of CO2.


SEA Fund: €800,000 to support local and sustainable agriculture

The winners of the second edition of the SEA Fund’s call for projects “Supporting local and sustainable agriculture”, launched on 3 May 2023, were announced on 18 December. Of the thirty-six applications received, twenty-six projects were selected by the Board of Directors. These were submitted by farmers, local authorities, producer groups, research establishments, associations, cooperatives and chambers of agriculture. These structures will receive support totalling €800,000.

This second edition complements an initial call for projects dedicated to local and sustainable agriculture, launched in 2021, for an amount of €500,000, thereby bringing the SEA fund’s initiative in favour of agro-ecological transition to €1.3 million.

Recognition of the quality of environmental measures

On 5 October, the interdepartmental monitoring committee for compensatory measures, bringing together all the local partners and players involved in the programme (CEN, naturalist associations, scientists, fishing federations, government departments), saluted, in a statement by the Deputy Director of DREAL (France’s national environment agency), the quality of the measures implemented and managed by LISEA, as well as the importance of maintaining the level of quality achieved over the long term.

The Deputy Director also emphasised the relevance and quality of the innovations implemented by LISEA, in particular the CompenSEA management application and the contracts signed with farmers. Well-accepted today, these contracts were innovative at the time and enabled high-quality environmental measures to be taken without pre-empting the land.


On 19 December, in the presence of the Conservatoire d’Espaces Naturels (CEN) de Nouvelle-Aquitaine, a press visit was organised with the Nouvelle-République de la Vienne to two environmental compensation sites (the Fontaine-le-Comte site and the Cassette spawning ground). This report presented the overall approach to environmental measures and the actions put in place in the Vienne department, where 700 hectares of environmental measures are in place.





Environmental measures


of the 736 ha of sites under contract monitored in 2023 comply with ecological specifications.

“CompenSEA” application praised by the French Office for Biodiversity

At a presentation of the “CompenSEA” tool for managing environmental compensation measures to the Office Français de la Biodiversité (OFB), which is responsible for coordinating the French government’s departmental bodies in the organisation of administrative and field inspections of compensatory measures taken for the SEA HSL, the public body acknowledged the application’s value in organising these campaigns and commended CompenSEA’s transparent approach.

Designed by LISEA, CompenSEA is the first digital platform for managing compensatory measures. This is an innovative solution for collecting, centralising and pooling data (mapping, types of measures, surface areas, species, environments, etc.) on the 330 compensation measure sites spanning the SEA HSL, spread over 3,800 hectares, with all the stakeholders involved (including government departments and environmental associations).


AI and DATA for the maintenance of the SEA HSL

Continuation of the ISO[IA] project

2023 will see the completion of the ISO[IA] project to monitor insulation faults in signalling stations, which are vital for maintaining the line’s safety and performance. A dedicated application has been created, designed to help the MESEA maintainer on a daily basis with precise monitoring of insulation and maintenance optimisation (in particular with simulations of insulation for up to 20 weeks). The application also provides the LISEA concessionaire with reliable indicators for knowing and managing the system assets over the long term.

ISO[IA] is already advancing the state of the art, thanks in particular to the isolation modelling work, by providing valuable input and enabling a better understanding of the influencing factors (weather conditions and railway events, such as points movements and train passages) for each of the 35 signalling stations on the SEA HSL. In practical terms, ISO[IA] is already helping to prevent and locate faults, so as to avoid incidents with a major impact on traffic.

As with all so-called data projects, ISO[IA] is based on the joint “SEACloud” platform developed by LISEA and MESEA, which enables existing data from the SEA HSL to be stored and leveraged, in particular thanks to artificial intelligence tools, and to develop a whole ecosystem of use cases, supporting the performance and safety of the SEA.

Partnership with HI! Paris and Léonard

As further recognition of the company’s expertise, LISEA was selected in 2023 to supervise an artificial intelligence project in partnership with HI! Paris (an interdisciplinary centre for artificial intelligence and data analysis at Ecole Polytechnique and HEC Paris) and Léonard, the VINCI group’s platform for identifying and accelerating innovative projects. This project, which will kick off in the first quarter of 2024, will involve four students in the application of learning methods for modelling the degradation of the SEA HSL with a view to predictive maintenance.