Marmaray project tunnel faced with a four-year delay

Once the line is finished, trains leaving Sirkeci Station and heading to Yenikapı will cover the 3.3-kilometer distance in 3.5 minutes. The tunnel will be between 60 and 83 meters deep at various points and will pass underneath some historic buildings and locations, including the Hocapaşa Mosque, Ebusuud Street, Mercan Mosque, Istanbul Boy’s High School, Beyazıt State Library, the Beyazıt Tramway Line, Laleli and the Russian Bazaar in Aksaray, before submerging below the waters of the Bosphorus.

The tunnel also passes 150 meters from the Grand Bazaar. Engineer Haluk Özmen, who is the Marmaray area director for the General Directorate of Railroad, Harbor and Airport Construction, or DLH, said the work is being done in accordance with standards set by the Cultural and Natural Heritage Preservation Board. "According to the information presented to us, the remnants of old civilizations lie 14 to 15 meters deep," he said. "Below that, there is bedrock, an untouched geological layer. We dig deep to avoid any archaeological damage or harm to the buildings." The entire Marmaray project, including the aboveground section, was supposed to be completed this year, but archaeological finds have slowed the process and pushed the new deadline out to 2013.

$500 million

Construction on the $3 billion project started in May 2004 with a ceremony attended by Prime Minister Recep Tayyip Erdoğan. To date, $500 million has been spent and the tunnel under the Bosphorus, which begins in Sarayburnu, has reached the opposite shore. Another tunnel will be dug from Sirkeci Station to open up a land exit.

The tunnel will eventually extend from Ayrılıkçeşme to Üsküdar Square; to date, it has reached the underground crossroad near the Business High School. The tunnel is expected to reach Üsküdar Station by June, and the existing underground train tunnel under the Maiden’s Tower in January 2010. The underwater connections for the tunnels have been completed, and their connection points cemented. The next step is the building of service roads.

According to information released by Özmen, the western ventilation shaft near the Hocatepe Tax Office, which will be transformed into the line’s Sirkeci station, has already been dug 50 meters deep. Work continues around the clock in the pilot tunnels, where the trains will travel in both directions.

Turkish and Japanese engineers have been working for four years on the western ventilation and exit shafts, where archaeological excavations were also conducted and completed. However, archaeological excavations are still in progress at the northern entrance of Sirkeci Station.