A 3,763.23-meter Ø1200 mm HDPE pipeline was installed along the seabed between Salacak and Sarayburnu by trench excavation. Additionally, an 859.60-meter Ø800 mm HDPE pipeline was submerged using the S-lowering technique in the Golden Horn between Eminönü and Karaköy. Various granulometric fillings were applied over the pipelines. To ensure stability and protection, 2,067.67 m³ of prefabricated reinforced concrete ring elements were manufactured, and sheet piles were driven for approach stabilization.