#2 -- Artificial heart
#3 -- Apache helicopter
#4 -- Pentium chips
#5 -- Rubberized asphalt
#6 -- Tasers
#7 -- Evaporative coolers
#8 -- Automotive air bags
#9 -- Charter schools
#10 -- Giant telescopic mirrors
Readers in an online survey judged water systems to be the most important innovation, ahead of more-modern developments like Apache helicopters, artificial hearts, evaporative coolers, charter schools and Intel's Pentium chips.
Water systems in the Phoenix metro area include canals that follow some ancient routes laid out more than 1,000 years ago: Roosevelt Dam, the Central Arizona Project, private and municipal water-treatment plants, and flood-control dikes and reservoirs.
Native Americans who lived in the Valley as far back as 1,000 years ago, if not earlier, figured out how to dig irrigation canals to distribute river water and irrigate crops. Anglo pioneers adopted the same principle beginning in the 1800s, helping launch agriculture and ranching as major industries. Canals continue to be a major source of domestic and agricultural water in the Phoenix area.
But in the early days, flooding was a major problem, as the Phoenix metro area lies in a valley with the Salt River at its base.
The completion of Roosevelt Dam in 1911, as well as other dams that were built later, helped control flooding and provided a place where water could be stored and distributed as needed.
The other major water project, the Central Arizona Project, is a diversion canal that sends Colorado River water for about 340 miles starting near Lake Havasu into central and southern Arizona. But it was a long time coming. The initial legislation was signed by President Lyndon Johnson in 1968, construction began in 1973 and the main canal was finished about 20 years later near Tucson.
-- Betty Beard
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