Central Arizona Project, Water management system in Arizona, United States.

The Central Arizona Project is a 336 mi (541 km) diversion canal that carries Colorado River water from Lake Havasu, near Parker, to a terminus 14 mi (23 km) southwest of Tucson. In the photograph it appears as a long, narrow strip of dark water between pale, straight earthen banks, winding through flat, dry terrain; a rectangular concrete structure spans the channel near the lower end.

Planning for this project started in the 1960s when Arizona fought for water rights from the Colorado River, and construction began in 1973. Completion of the main route in 1993 marked the end of this massive engineering effort.

The canal's name appears in the Colorado River Basin Project Act of 1968, the law signed by Lyndon B. Johnson that created it. A visitor can spot the Mark Wilmer Pumping Plant at the Lake Havasu intake, where six units of 49,216 kW each lift water 244 m. The project is often cited as the state's most celebrated bipartisan achievement of the 20th century.

The best time to visit is October through April when temperatures are more comfortable for exploring the canals and access points. Information about public areas and viewpoints is available through local visitor centers or the project website.

The system requires 14 pumping stations to lift water up to 900 meters uphill at certain points, making it one of the state's largest electricity users. This massive power requirement is what made settlement possible in Arizona's driest regions.