Delays push up cost of Turkish rail project
Turkey's ambitious Marmaray subsea rail project is running $500 million over budget as a result of delays caused by archaeological digs and construction challenges.
The Turkish Ministry of Transport's Marmaray project will link Istanbul's Asian and European sides through a tunnel under the Bosphorus Straits. It is one of the world’s major transportation infrastructure projects, and is currently due for completion in October 2013, four-and-a-half years later than originally planned.
'Today's Zaman' newspaper quotes official documents showing the updated cost, based on the revised schedule and changing economic conditions. The $500m increase represents a rise of 50 per cent on the cost of tunnel and station construction.
The 76.3 km line will connect with Istanbul’s urban transport network. With a capacity of 75,000 passengers per hour in each direction, it will considerably reduce traffic congestion in the city.
The link includes an immersed tube tunnel of 1.4 km accessed by a 10 km bored tunnel. At 58m below sea level it will be the world's deepest immersed tube tunnel, constructed from the largest prefabricated tunnel sections ever built. Around 90 pumps are employed to remove water from the works, including 40 "puddle suckers" which supplier Tsurumi says have not generally been used in projects of this kind before.
In spite of the impact on construction, the archaeological excavations have proved extraordinarily fruitful, revealing thousands of artefacts including 34 ships from the ancient port of Theodosius and some human skeletons thought to date back to 6500 BC.
The AMD consortium, led by Alstom Transport, is carrying out Phase 2 of the Marmaray project, covering the construction of new lines and the refurbishment of existing ones. As consortium leader. Alstom recently awarded Nexans the contract to supply 1350km of specialised signalling and low-voltage power cable for the link.