Middle Route South-to-North Water Diversion Scheme Phase I is an extremely large inter-basin water transfer project, which diverts water to Beijing and Tianjin cities from Danjiangkou Reservoir of the Hanjiang River, a tributary of the Yangtze River. The trunk canal has a total length of 1,432 km. The Yellow River Tunnel Project is the tunnel structure under the Yellow River channel. It is the largest scale key project with the most complicated technology and controlling the schedule.

The total length of the tunnel project is 19.3 km. The under-river tunnel is 3,450 m long, excavated by the tunneling shield machine, advancing from the north to the south bank of the Yellow River.