At the end of the tunnel: collective success

Before being given the name Florence, the tunnel boring machine had already excavated another tunnel beneath the streets of Paris. 

Indeed, between 2018 and 2019, Implenia’s teams used this impressive machine to complete a section of line 15 as part of contract T2c. At the time, it was known as Steffie. Aydan Murphy was part of this adventure and was among the first to discover Steffie, on the day its cutterhead was delivered to the site. 

Aidan Murphy: A calling born underground 

A graduate in civil engineering from Canada, Aidan developed a passion for underground works during his final-year internship on the Paris Metro Line 14 project. The world of tunnel boring machines immediately captured his interest, and in 2017 he joined Implenia on Line 15. There, he was involved in every stage of the project — from the design and manufacturing of the TBM, to the excavation of the very first tunnel of the Grand Paris Express, and through to the handover of the structures to the client. Over the years, he has built up comprehensive, multidisciplinary, hands-on experience in the field. 

Aidan at the heart of the handover process 

As a methods and construction engineer, Aidan joined the Line 17-1 project in 2024 to oversee the handover of six ancillary structures (stations, shafts, emergency exits, etc.). On site every day, he coordinated the finalisation of the works and contractual follow-up, ensuring that all structures met the client’s expectations. 

“During the handover phase, an almost daily presence on site was essential, in close coordination with the project management team. This stage went far beyond simply monitoring the works. It required constant critical thinking. Some situations led us to question — and in some cases adjust — the client’s initial design,” explains Aidan. 

Precision, rigor, and coordination  

His role on Line 17-1 demanded strict rigor: contract management, site supervision, record-keeping, and proficient use of the DMS (Document Management System). Aidan carried out his responsibilities efficiently, within a framework of trust and autonomy granted by the consortium. 

At the height of the project, up to 300 workers were simultaneously on site, representing a wide range of trades: tunnel boring machine operators, masons, electricians, engineers, logisticians, and maintenance teams. This daily coordination required precise monitoring, detailed schedules, and constant communication between teams to ensure both safety and efficiency. 

All reservations cleared: the project is officially closed

Thanks to everyone’s commitment, the final OPRs (Pre-Acceptance Operations) were successfully completed, and all reservations have now been cleared. Line 17-1 can thus be considered fully handed over, marking the collective success of a major project led by Implenia. 

Until the very last day: the faces of project completion 

As the bulk of the work came to an end, the final team members remained on site, ensuring the project’s smooth closure right to the very end.