Mobility · Urban planning · Greater Geneva · October 2026
The extension of tram 15 to Saint-Julien-en-Genevois will not go ahead as originally planned. On 16 July 2026, the Federal Administrative Court (TAF) annulled the approval of the plans for the Swiss section, between the ZIPLO and the French border. On 2 September, the Geneva Council of State announced that it would not appeal: a new project must be designed.
The question: how can this cross-border link be built without repeating the legal and environmental problems that blocked the project?
I. A strategic extension, blocked by the courts
A. The tram already serves the ZIPLO
The first stage has been in service since December 2023:
- Section: Les Palettes – ZIPLO (Plan-les-Ouates industrial zone).
- Length: 2.7 km.
- Four new stops: Curé-Baud, Le Rolliet, Cherpines and ZIPLO. The Cherpines stop is to be served as the new neighbourhood develops.
- Frequency: about one tram every 4 to 5 minutes at peak times.
The planned extension was then to cross Perly-Certoux and the border and reach Saint-Julien-en-Genevois station.
B. Why did the court block the project?
On 10 July 2023, the Federal Office of Transport (FOT) had approved the plans for the ZIPLO – border section. Opponents challenged this decision. After three years of proceedings, the TAF annulled it on 16 July 2026.
- Main reason: the access road planned alongside the tram, whose route encroaches on farmland.
- Legal reason: the FOT’s competence to rule on road works.
- Context: the project dates from a 2013 decision of the Grand Council; since then, mobility needs and environmental issues have changed considerably.
Key point: the court questions neither the principle of the tram, nor its route, nor its public interest. It challenges the measures that accompany it.
II. A new project to design
A. The bypass road abandoned
On 2 September 2026, the Council of State decided not to take the case to the Federal Supreme Court: continuing the proceedings would have delayed the project by several years, with no guarantee of success. The bypass road originally planned to make way for the tram is abandoned, in agreement with the French authorities and the appellants.
Next steps announced:
- Set up a new project governance structure by the end of 2026.
- Draw up a new tram project, then submit it to a new plan approval procedure.
- Continue coordination with Swiss and French local authorities.
B. Which stakeholders and what timeline?
| Stakeholder | Role |
|---|---|
| State of Geneva | Political leadership and new project governance |
| Federal Office of Transport (FOT) | Approval of the plans for the Swiss section |
| Geneva Public Transport (TPG) | Operation of the tram network |
| Municipality of Perly-Certoux | Local coordination, traffic |
| Communauté de communes du Genevois and Town of Saint-Julien-en-Genevois | Project owners on the French side |
On the French side, the preparatory works are already done: started in October 2022, the relocation of utility networks (notably on Avenue de Genève and around the station) was completed in 2024.
Timeline: no opening date can be announced at this stage. A new project and a new administrative procedure are needed.
In the meantime, the canton plans two measures:
- Increase the frequency of cross-border bus 80 between Saint-Julien and Geneva.
- Widen the Bardonnex customs platform, to shift traffic to the motorway and relieve the small border crossings of the southern municipalities.
III. What is being debated
- Farmland. The appellants, shopkeepers and residents of Perly, opposed the bypass road planned for the tram, considered to take up too much farmland. This is one of the main grounds of the ruling.
- Crossing Perly. Without a bypass road, the tram would run along Route de Saint-Julien, which is narrow through the village, sharing the road with cars. According to the CITraP association, this would mean cutting traffic from about 18,000 to 5,000 or 6,000 vehicles a day.
- Transit traffic. In Perly-Certoux, the VIVRE Perly-Certoux movement denounces the noise, pollution and bus delays caused by traffic heading to the ZIPLO, the motorway and the Bardonnex customs post. It sees the tram as an opportunity to shift people to public transport.
- Delays. The State gave up the appeal to avoid years of proceedings. CITraP supports this choice, but estimates that the extension will be delayed by at least five to six years.
- The French reaction. French local authorities refuse to wait five or six years without a solution. Pending the new project, they are calling for immediate measures to speed up bus 80 and reduce congestion in Saint-Julien (Tribune de Genève).
Key takeaways
- Tram 15: in service to the ZIPLO since December 2023.
- Extension to Saint-Julien: the project approved in 2023 has been annulled.
- Main cause: the access road and its impact on farmland.
- Next: new governance by the end of 2026, then a new project.
- Opening: date unknown.
Sources: Geneva Council of State, press release of 2 September 2026 ; Council of State, response to the TAF ruling (July 2026) ; Tramway du Genevois (CCG – Saint-Julien-en-Genevois) ; Municipality of Plan-les-Ouates ; CITraP Genève ; VIVRE Perly-Certoux ; Tribune de Genève ; 20 minutes, 2 September 2026.
