Last Wednesday, twelve lucky AIWC members had a guided tour of the Jet d’Eau facilities and one very lucky member had the privilege of turning the jet on for the day.

Photo courtesy of Fay R

Photo courtesy of Fay R

Our tour began lakeside at the information plaque facing the Jet. Our guide for the morning, Anna, explained the history of the Jet d’Eau and detailed facts and figures about its construction and operation. We learned:

  • Don't miss this viewfinder lakeside - it helps you estimate the height of the Jet d'Eau

    Don’t miss this viewfinder lakeside – it helps you estimate the height of the Jet d’Eau. Photo courtesy of Fay R.

    The first jet d’eau in Geneva was at the hydraulic plant at La Coulouvrenière on the Rhône river.  When the machines were turned off each night, workers had to try to control excess pressure on the system’s pumps. To solve the issue, a vertical release valve was built and its jet reached 30 meters high; a vertical valve was necessary because a horizontal release valve would have destroyed the river’s banks.

  • The La Coulouvrenière facility dates to 1886 and was in operation until 1990. The smaller jet became a popular attraction for locals and tourists alike, so in 1891, the city decided to erect a new, taller jet in the harbor.
  • A pumping station was built for the jet in 1951 using water from the lake to power the Jet d’Eau. The Jet d’Eau is the only SIG facility that has to be manually operated and it has a team of caretakers who switch it on and off each day.
  • The plume of water reaches an average height of 140 meters and water travels at a velocity of 200 km/h when exiting the Jet.
  • The Jet d’Eau has a specially-designed nozzle that gives the water its distinctive shape and color. Up close, you can see where air is sucked into the water stream at the base of the nozzle.
  • The Jet’s nozzle also has a protective casing to deter vandals during off hours.
  • The Jet costs approximately CHF 800,000 to operate annually.
The nozzle of the Jet d’Eau, with its protective casing retracted
A view of the Jet d’Eau nozzle and entrance to the pump room

After learning about the Jet, we followed our guide down the quai and descended into the pump room. The Jet d’Eau is powered by two groups of motor pumps that each pump at the rate of 250 liters per second. These pumps, labeled Jura and Salève, are serviced once each year and are removed from the pump room by crane. The pump room is mostly submerged into the lake, and it has an air conditioning unit to prevent the pumps from overheating during warmer months.

Entrance to the pump room
Two groups of pumps power the Jet d’Eau
Photo courtesy of Fay R

Finally, it was time to turn on the jet! We were granted access to the control switches by one of the jet’s caretakers, and Living in Geneva’s very own Alpenhorn had the honor of hitting the “on” button to start the jet for the day.

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Thanks to our tour organizer, Alpenhorn; our guide, Anna; and to SIG for allowing us a unique “insider’s” look at one of Geneva’s main attractions.

For more information about the Jet d’Eau, click here. To learn more about guided visits of the Jet d’Eau, click here (in French); SIG also offers guided tours of its other facilities – click here to learn more (in French).

We are a group of international women living in Geneva, Switzerland.  If you would like to join the AIWC, please visit our website at http://www.aiwcgeneva.org/