How did the Hohokam use canals along the Gila and Salt rivers?

The Hohokam people, who inhabited the semiarid regions of present-day Arizona, developed the most sophisticated irrigation canal networks in pre-Columbian North America to support their agriculture.1

Their use of these canals evolved significantly over time:

• Early Development: During the Pioneer Period, the Hohokam constructed their first irrigation channel—a 3-mile (5-km) canal in the Gila River valley—to direct river water to their fields of corn.1
• Engineering Improvements: As their culture expanded during the Colonial Period, they refined their techniques by making canals narrower and deeper. This design adjustment was intended to minimize water loss caused by ground absorption and evaporation.1
• Expansion and Complexity: By the Sedentary and Classic periods, the Hohokam had created extensive and complex irrigation systems to support the cultivation of corn, cotton, beans, and squash.1
• Legacy: At their peak, these networks spanned more than 150 miles (240 km) in the Salt River valley. The engineering was so effective that some of these ancient canals were renovated and returned to use during the 20th century.1