By Sandy Guthrie24 August 2010
Both tunnel boring machines have broken through at Keleti station on the Budapest, Hungary, Metro Line 4, completing the two running tunnels for the new line from Kelenfold to Keleti.
The 7,3 km long first phase of Line 4 will include ten stations, and will connect with the existing Metro Lines 2 and 3, as well as the mainline network at Kelenfold and Keleti.
The Mott MacDonald Group engineering and development consultancy provided specialist input on tunneling methods and designed the ventilation system. It also completed the detailed design for the sprayed concrete lined (SCL) tunnel at Bocskai Street Station, and provided advice on settlement, SCL and the underpassing of the river Danube.
It was also environment consultant for the project, responsible for noise and vibration impact assessments for interior construction work at all 10 stations along the new line. It provided detailed environmental services for three stations.
The Metro Line 4 project is costing € 1.2 billion.