Central Arizona Project

waterway, Arizona, United States

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June 24, 2026

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The Central Arizona Project (CAP) is a 336-mile (541-kilometer) system of structures that conveys water from the Colorado River to south-central and southern Arizona. Authorized in 1968, it was completed in 1993 and is crucial for agricultural and municipal water supply in the Phoenix and Tucson areas. The project was born out of a long legal battle, culminating in a 1963 U.S. Supreme Court ruling that affirmed Arizona's right to a significant portion of the Colorado River's water. The CAP is a vital component of water management in the arid Southwest.123

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Colorado River
Economic development
…way for funding of the Central Arizona Project (completed in the 1980s), which transferred water to the cities of Phoenix and Tucson. The project consists of a mountain tunnel through which water from the southern end of Lake Havasu is pumped up and into an aqueduct that flows southward to…
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…way for funding of the Central Arizona Project (completed in the 1980s), which transferred water to the cities of Phoenix and Tucson. The project consists of a mountain tunnel through which water from the southern end of Lake Havasu is pumped up and into an aqueduct that flows southward to…
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Phoenix
City site
…the Colorado River via the Central Arizona Project (CAP), an artificial waterway 336 miles (541 km) long extending from Lake Havasu on the California border to Tucson. In addition, water from subterranean stores is piped into the valley from outlying areas. In the past, virtually all of the region’s water…
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…the Colorado River via the Central Arizona Project (CAP), an artificial waterway 336 miles (541 km) long extending from Lake Havasu on the California border to Tucson. In addition, water from subterranean stores is piped into the valley from outlying areas. In the past, virtually all of the region’s water…
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Arizona
Development of commercial agriculture
Congress authorized the Central Arizona Project, a massive system of pumps and canals to conduct water from the Colorado River to the Phoenix and Tucson areas; the project was completed in 1993.
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Congress authorized the Central Arizona Project, a massive system of pumps and canals to conduct water from the Colorado River to the Phoenix and Tucson areas; the project was completed in 1993.
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