Avax Ghella Alstom win Athens Metro tender
28 October 2020A consortium led by Avax and comprising Ghella and Alstom has won the tender for building the first phase (Section A) of Line 4 of the Athens Metro, hailed as one of Greece’s biggest public projects over the next decade. Construction is scheduled to begin in 2022.
The US$1.8bn Line 4, section A contract involves the 12.8km-line from Alsos Veikou to Goudi, involving 15 stations, primarily in the city centre.
Around 10.3km of the twin-track 9.5m OD tunnel will be excavated by TBM and segmentally lined in a 7+1 configuration. In some places, the tunnel will be triple tracked. Around 800m of NATM will be required, including around Akadimia and Evangelismos stations, but particularly beneath sensitive areas, such as historic buildings, and for connecting tunnels between neighbouring stations.
Planned over a decade ago, the project has seen a few recent changes, such as an additional station added at Ano Kypseli (Elikonos) due to pubic demand, and other minor relocations.
Athens is a very densely populated ancient city and tunnelling beneath historic sites will be fraught with problems. Experience from the city’s Line 3 metro – and from the Thessaloniki metro currently under construction – has shown that stumbling upon archaeological relics could result in severe delays, even alignment changes.
The geology along the alignment is expected to comprise Athens schist, sandstone, silts, shales, ophiolites and limestone. Much of the alignment will be below the water table, with overburdens ranging between 12-74m.
Avax managing director Konstantinos Mitzalis stated: “This is undoubtedly a landmark project, not only in terms of upgrading the quality of life and commuting for the capital city’s residents, but also for the key role that infrastructure projects can play in Greece’s course towards economic growth.”
Line 4 has been dubbed the ‘U-line’ due to its plan configuration on the Athens transport map. It comprises five phases (Sections A, B, C, D and E) totalling 38.2km and 35 stations.
In addition to Line 4A, the Avax-Ghella-Alstom consortium is currently constructing the 6.5km twin-track tunnel of the Line 3 extension from Haidari-Athens to Piraeus, expected to be completed in 2022. The stations of Aghia Varvara, Korydallos and Nikaia were opened recently.
