“Water level hit record low this year, fortunately they put in action the third straw”, a guide told summer tourists visiting Lake Mead. “People come here to see the volcanic rocks emerging from the lake, leaving the growing white belt caused by drought uncovered”, he added, referring to the artificial lake created by the Hoover Dam. This famous hydropower project is located on the Colorado River, which brings potable water to 40 million people, irrigates five million acres of farmland and contributed $1.4 trillion to the economy. From the Rocky Mountains to Mexico, the river runs 2,330 kilometres through seven U.S. stations and two countries. But the rise in temperatures and an obsolete way to manage this water resource have led to the river dwindling to historic lows.

The crisis besetting the Colorado River led the Southern Nevada Water Authority (SNWA) to have Webuild build the Third Intake, the latest installment to an existing pumping system at the lake. The project set industry records given its complexity. It included an access shaft 200 metres deep on the shore of the lake, and a tunnel that stretches for 4.6 kilometres under the lake from the base of the shaft.

Water from the lake is drawn by an intake pipe installed at its bottom. It is then sent down the tunnel to the shaft, where it is pumped out and treated before being sent to the distribution network responsible for 90% of potable water for the state of Nevada, which includes Las Vegas with its 2.6 million residents.