PRESS RELEASE
ELLINIKO METRO S.A. hereby makes the following announcement:
The construction of the tunnel of Metro Line 4 is being executed in full compliance with the most modern safety standards related to the execution of tunneling works in urban environment.
“Athina” Tunnel Boring Machine (TBM) has already successfully bored “Goudi-Evangelismos” tunnel section and works for its disassembly have commenced. Boring works are being executed by “Niki” TBM in “Alsos Veikou – Evangelismos” section, with the TBM heading to DIKASTIRIA Station having passed underneath Kypseli Square.
During tunnelling activities, a comprehensive monitoring and management plan is implemented. This plan consists of the following, namely:
- continuous instrumental monitoring on a 24h basis of the overlaying structures located within the influence zone of the TBM passage;
- predetermined action plan, which is activated on a preventive basis whenever the recorded movements approximate the predetermined alarm limits.
As of 08.05.2026, TBM activities have been suspended due to unforeseeable and undetectable conditions identified in the particular weak geological subsoil, which had already been studied during the design phase of the Project. The option to suspend tunnelling activities came as a result due to identified ground displacements that exceeded those predicted in the design. From the very beginning, ELLINIKO METRO S.A.’s and the Contractor’s executives have visited all buildings, have conducted on-site inspections and have informed the tenants on the actual extent of the subject matter.
It is stressed that, on basis of the data available to date further to the pertinent on-site inspections, no issues pertaining to the structural integrity or any impact on the bearing structure have been detected in any building, while the instrumental monitoring reveals no further progression of the phenomenon.
At the same time, the Contractor of the project, as required, has already initiated and is carrying out repairing works to the cracks, at its own care, expense and under its responsibility, in cooperation with the owners and tenants of the buildings.
Further to the relevant instruction given by ELLINIKO METRO S.A. to the Contractor of the project, and in an effort to resume TBM operations, a technical investigation is currently underway with the assistance of independent specialized technical consultants from Greece and abroad. It should also be noted that the project TBMs are state-of-the-art machines, designed to excavate tunnels in particular soil types, capable of continuously monitoring and adapting to the geotechnical conditions prevailing each time.
ELLINIKO METRO S.A. possesses over thirty years of experience in tunneling activities in urban environments, and as far as the Construction project of Line 4 is concerned, it has adopted the most advanced metro construction expertise. It is, therefore, able to assure that safety constitutes the highest and absolutely non-negotiable priority in its design and operational activities.
