Grand Paris Express: Europe’s largest infrastructure project (2024)

A project of colossal proportions and incredible complexity.

The scale and the ambition of the Grand Paris Express is vast, and it is widely seen as the project of the century. The ambition was to improve connectivity across the city by building 200km of mainly underground rail and 68 new stations. Working on a project this large in a dense city introduced a wide variety of challenges:

Project coordination

The Grand Paris Express is the biggest infrastructure project in Europe. Turning the plans into reality means managing countless building trades and 1000s of subcontractors. We’re simultaneously managing 300 construction projects while controlling for hazards and collaborating with multiple stakeholders.

Difficult conditions

Tunnelling beneath a dense city and a geological terrain that humans have altered for millennia represented a serious engineering challenge.

Extremely strict schedule

This project has always had an ambitious schedule with major milestones planned between 2022 and 2035. Station Saint Denis Pleyel must be completed in time for the 2024 Paris Olympics.

Working closely with consortium partners.

Our ability to deliver a transport infrastructure project as vast as the Grand Paris Express relies on the multidisciplinary nature of Egis. Along with the extensive skills, experience and know-how of our experts.

We are conducting systems project management for Lines 15, 16 and 17 in a consortium with various partners. We are also acting as systems project managers, including overseeing the rolling stock on Line 18.

We’re also responsible for general scheduling, planning and coordination (GSPC) missions for Lines 15 South, 16 and 17, in partnership with Planitec BTP and Ingérop and for Line 14 North and South extensions in partnership with Planitec BTP. This involves the development of a system vision to anticipate interface problems.

Alongside our partners, we’re responsible for Line 16’s infrastructure, the Line 15 depot facility and were in charge of the project management of the infrastructure of Line 15 East until the contract changed into the design and build. We are also involved in the process of designing Line 15 East and West.

Through all of these missions, we have been a critical player in the Grand Paris Express. The work has required demanding coordination, organisation and communication processes.

• 2022 - 2025: Eastward extension of Line 11, from Rosny-Bois-Perrier to Noisy-Champs.
• 2024: Extension of Line 14 to Saint-Denis in the north and Orly airport in the south.
• 2024 - 2030: The Paris orbital Line 15 will connect with most metro and RER lines.
• 2025: Entry into service of the southern section of line 15 (Pont de Sèvres - Noisy-Champs).
• 2024 - 2030: Line 16 between Saint-Denis and Noisy-Champs, mainly serving the Seine-Saint-Denis region.
• 2026: The first sections of Lines 16 (Saint-Denis Pleyel - Clichy - Montfermeil) and 17 (Le Bourget RER - Le Bourget Aéroport), which will be brought into service in their entirety in autumn 2026.
• 2026: Completion of the central section of Line 18 between Massy - Palaiseau and Saclay.
• 2028: The last section of Line 16 (Clichy - Montfermeil - Noisy-Champs) and the second section of Line 17 (to the Villepinte Exhibition Centre).
• 2024 - 2035: Line 17 between Saint-Denis and Paris-CDG airport. Includes an elevated section running on a viaduct.
• 2027 - 2035: Line 18 between Orly airport and Nanterre, via the Saclay Plateau and Versailles. This includes a long, elevated section.
• Some sections are planned for later, such as the Versailles-Nanterre section of Line 18. The new network should be fully operational by 2035.

Highly technical design and project management.

We have been deeply involved in the Grand Paris Express since day one. Our teams have collaborated on all aspects of the design, planning and research studies. They are now working on its construction and project management, coordinating 1000’s of workers from multiple subcontracting companies to a tight schedule.

At the outset, our use of Building Information Management (BIM) technology helped optimise the design and construction phases of the project. 3D digital models helped facilitate decision-making, and having access to the as-built model will also support the lines’ maintenance for decades to come.

Our teams have also helped plan major civil engineering works. We are responsible for 9 of the 20 colossal tunnel boring machines digging up to 50m below the surface.

Over the course of the project, we have conducted over 3,000 geotechnical surveys to build up a detailed map of the region’s subsurface.

Trains are expected to run at speeds of between 60 km/h and 120 km/h with a frequency of at least one train every 4 minutes. We needed to design high-level automatic management for operations across this vast 200km railway network.

A project that shows what France can do.

This hugely ambitious undertaking addresses the limitations of the existing Paris Metro, boosts the city's prestige and supports the transition to low-energy mobility.

Connecting neighbourhoods

The new lines will provide multiple benefits to citizens. It will connect those living in isolated communities on the city’s outskirts to jobs closer to the centre and other suburbs. At the same time, it will allow people to quickly travel around the Paris region without crossing through the centre of the city.

Reducing emissions

By encouraging citizens to use public transport, the automated new rail line will reduce CO2 emissions by some 27.6 million tonnes by 2050.

Vibrant new neighbourhoods

The creation of 68 new metro stations will be a boost for local economies around the stations. New homes, businesses and community spaces are also planned.