Lake Mead intake hydraulic tunnel, Las Vegas

Name of Project:

Lake Mead intake hydraulic tunnel, Las Vegas


Southern Nevada Water Authority – SNWA, Las Vegas, Nevada U.S.A.

Total value:
€371 million

Lake Mead is one of the largest artificial lakes of the Unites States. It is formed by the Hoover dam, which dams the Colorado river at a few kilometres from Las Vegas.

The project involved the construction of a system for collecting and transporting the waters of Lake Mead, located approximately 30 kilometres south-east of the city of Las Vegas (Nevada), in order to increase the supply of water, approximately 4.5 million cubic metres per day, for drinking and domestic use in the urban area of Las Vegas.
The works involved the construction of an access shaft, excavated in the rock on the shore of the lake, approximately 200 m deep and with a diameter of 9 m. A tunnel was constructed at the bottom of the shaft under the lake bed approximately 4,600 m long and with an excavation diameter of 7.2 m. The intake work is located at the end of the tunnel, approximately 100 metres below the surface of the lake, made from a pipe-shaped tubular steel structure with a diameter of 6 m and a height of approximately 30 m.
The water, drawn in from the bottom of the lake through the intake work openings, is directed along the tunnel to the access shaft, from where it is pumped to the treatment plant on the surface.

Its functioning ensures 4,500,000 m3 of drinking water and water for domestic use to the urban area of Las Vegas. Water supply is guaranteed even in the case of severe drought.

Awards. In September 2016 Tunnel Business Magazine (TBM), one of the industry’s leading magazines, assigned to the project the “Tunneling Achievement award of the year”. In November 2015 the Lake Mead Tunnel was nominated “Project of the Year” by the International Tunnelling Association in Switzerland, and, in December 2015, was awarded the “Project of the Year” prize by the New Civil Engineer (NCE), a prestigious organization of the British Tunneling Society. The project also won the (Engineering Excellence Award) of the American Society of Civil Engineers (ASCE) for the State of Nevada.

Weight: 1,250 tonnes
Tunnel length  4.6 km
Excavation diameter: 7.22 m
Underground excavations: 30,000 m3
Internal diameter: 9.15 m
Maximum pressure: 15 bars

Last update: 02/10/2019