Peoria (/piɔːriə/) is a city in Maricopa and Yavapai counties in the U.S. state of Arizona. Located primarily in Maricopa County, it is a major suburb of Phoenix. According to 2010 Census Bureau releases, the population of the city is 154,065. Peoria is currently the sixth largest city in Arizona for land area, and the ninth largest for population. It was named after Peoria, Illinois. (The word peoria is a corruption of the Illini word for “prairie fire”.) Peoria is now larger in population than its namesake. It is the spring training home of the San Diego Padres and Seattle Mariners who share the Peoria Sports Complex. In July 2008, Money magazine listed Peoria in its "Top 100 Places to Live".
Peoria sits on flat gently sloping desert terrain in the Salt River Valley, and extends into the foothills of the mountains to the north. Like all desert towns, the key to Peoria’s settlement was water. Seasonal rainfall and runoff from mountain snowmelt filled the Salt River, at times flooding the valley and wiping out months of backbreaking labor. If the area was to become habitable and productive all year, the cycle of flood and drought had to be replaced with a reliable supply of water that could be controlled year-round. The pioneers turned to irrigation. In 1868 John W. “Jack” Swilling organized a group of men to dig the first modern irrigation ditch in the Salt River Valley. Their success enticed more people to settle in the area and reap the benefits of a revitalized irrigation system.
By 1872, there were eight thousand acres (32 km²) of land under cultivation in the valley and a thriving community had been built along the Salt River. Over the years irrigation companies sprung up and in the next three years three canal systems—the Maricopa, Grand, and Salt River Valley—were constructed, each allowing sustaining growth in the Valley. Visionary settlers began to imagine the potential income to be had by reclaiming the rich desert lying higher up the slope above the recently completed Grand Canal; in 1882, the Arizona Canal Company was organized to do just that. The proposed canal would be larger than its approximately 80,000 acres (320 km²)—including the site that would soon be Peoria—to a more consistent and regulated water system.