1. General

This is a comprehensive large-scale water resources and municipal infrastructure project for supplying water to Lanzhou City. YREC is the EPC contractor.

The Project includes five parts: water intake, conveyance, diversion, purification and distribution facilities. The water transfer line is 31.5 km long, the design flow is 26.3 m³/ s, and the annual transfer capacity is 830 million m³. Two new water treatment plants have a capacity of 1 million t/d and 0.5 million t/d respectively.

The TBM construction section of the water transfer tunnel is 24.78 km long, and the drill & blast section is 6.47 km long.

2. Challenges

Many construction areas and long construction routes. Temporary construction works include10 adits, 7 shafts and 24 electricity supply sites. Water tunnels extend for a long distance, the pipeline crosses a wide range of area, and the land acquisition problems and cultural environment are complex. The Project is located in remote mountains with a big number of work faces and high safety risks.

Many stakeholders involved, complex for coordination. More than 30 parties are involved, including 13 construction subcontractors, 9 supervision units, 3 quality inspection stations, 3 follow-up auditing units and several third-party testing units.

The Project crosses the railway line in multiple positions, involving railway-related construction procedures and special construction methods.

3. Achievements and Innovations

Research & development and operation of China’s first TBM. China’s first TBM was developed, and the New Technical Standard for Design and Construction of Double-shield TBM Pressure Tunnels was drafted, which fills the gap in this field in China. The single-layer segment lining scheme for pressure tunnel was applied for the first time in China.

Artistic design for infrastructure. YREC adopted an artistic design concept, and the two water treatment plants have attractive appearances and become local landmark buildings.

Digital management. The Digital Construction Site and the 4D Progress Monitoring System were established, and the Digital and Intelligent Project Management Platform was developed.

Brand publicity. Media platforms such as WeChat Official Account and mobile APP were created, more than 70 large-scale external visits received, 12 training exchanges organized, and more than 300 times reported by official media. The Project has become a demonstration EPC project of China.