TURKEY: Construction of the long-planned rail tunnel under the Bosporus is expected to start in June, following the signing of a turnkey construction contract in early April. This was due to be followed by ratification of the financing package before the end of the month.

Japan Bank for International Co-operation is providing the bulk of the funding for the Marmaray project in a deal with the Turkish government. The construction contract has been awarded to a Japanese-led consortium of Taisei, Kumagai, Fumi and Gama, at a cost of ´89·7bn.

Due to be completed by 2008, Marmaray will see the creation of a 76·3 km high-capacity rail link from Gebze to Halkali, including 13·3 km in tunnel running from Yenikapi on the European side to Sogutlucesme on the Asian side. The 1·8 km cross-Bosporus section will be built as an earthquake-proof immersed tube, assembled from 18 sections, whilst the approach tunnels under Istanbul and Haydarpasa will be bored.

The project includes reconstruction of 41 stations on the existing railways, where a third track will be laid to raise capacity. All platforms will be lengthened to 180m. Underground intermediate stations are to be built at Sirkeci and Uskudar on the tunnelled approaches, together with a new metro and light rail interchange at Yenikapi.

Signalling will be designed to allow 2min headways, giving a design capacity of 75000 passengers/h in each direction.