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The Mark Wilmer Pumping Plant, between Lake Havasu City and Parker, is the facility Central Arizona Project uses to draw water from the Colorado River.

From Lake Havasu, the CAP aqueduct system carries water 336 miles throughout central and southern Arizona, ending at the southern boundary of the San Xavier Indian Reservation southwest of Tucson.

Here are a few other facts you might not know:

  • The Mark Wilmer Pumping Plant was the first plant built in the CAP system, with construction beginning in 1973. Construction lasted until 1985, and cost $63.8 million.
  • Right at the outset, the first engineering challenge was pumping water from the river and then lifting it 800 feet up Buckskin Mountain where it is released into the seven-mile long Buckskin Mountain Tunnel.
  • Mark Wilmer Pumping Plant
  • The tunnel took five years to complete, from 1975 to 1980. This phenomenal construction feat was captured on video and is a fascinating look at the engineering marvel that is CAP.
  • The seven-mile tunnel is comprised of 28,500 concrete segments, each only five feet wide.
  • The Mark Wilmer Pumping Plant features six 66,000-horsepower pumps. Each pump requires 50 megawatts of power, more than is required for the entire city of Lake Havasu on the hottest day of the year.
  • When all are running, they could:
    - Fill an Olympic-sized swimming pool in less than three seconds
    - Use the amount of energy that would be used by 300,000 homes
    - Move more than 100 million gallons of water per hour
  • The Mark Wilmer Pumping Plant is named for Phoenix attorney Mark Wilmer whose most significant professional achievement was in 1952 when he successfully represented the State of Arizona before the U.S. Supreme Court, thus establishing Arizona’s right to its allotment of Colorado River Water.

And finally, on April 9 of this year, the Mark Wilmer Pumping Plant reached a milestone total of 40 million acre-feet pumped since 1985!

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