A major challenge for the metropolis of Istanbul is sewage treatment. One of the largest and most modern sewage plants in Europe was built adjacent to the district of Ambarli in the European part of the city. In the first phase, the plant was planned with a capacity of 400,000 cubic meters of sewage per day – sufficient capacity for two million people.

Tunnelling at depths of between seven and 140 meters, the M-1070M Earth Pressure Balance Shield, broke all Turkish tunnelling records, returning impressive weekly advance rates of 150 meters with simultaneous segment installation. The 4,800-meter-long tunnel is designed to carry the main sewer from the city area.