Central Arizona Project

Central Arizona Project
Name	Central Arizona Project
Location	Arizona, United States
Length	336 miles
Begin	1968
Complete	1993
Owner	Arizona Department of Water Resources
Operator	Central Arizona Water Conservation District

Central Arizona Project is a large-scale water diversion and delivery system in Arizona designed to transport Colorado River water to central and southern parts of the state. Conceived in the mid-20th century amid disputes involving Colorado River Compact, Bureau of Reclamation, and western water law, the project links the Glen Canyon Dam region with urban centers such as Phoenix, Arizona, Tucson, Arizona, and tribal lands including the Gila River Indian Community. It functions within a complex network of federal, state, tribal, and municipal institutions, and has been central to debates over water rights in the United States, arid land agriculture, and southwestern urban growth.

History

Authorization for the project followed political negotiation among figures like Barry Goldwater, John McCain, and federal agencies such as the United States Bureau of Reclamation. Early planning connected to landmark measures including the Colorado River Compact and later litigation such as Arizona v. California (1963). Construction milestones paralleled large infrastructure programs overseen by presidents including Lyndon B. Johnson and administrations of the United States Department of the Interior. Opposition and support emerged from stakeholders like the Hoover Dam region interests, Salt River Project, and tribal nations represented by the Tohono O'odham Nation leadership. Water policy debates involved institutions such as the U.S. Congress and legal frameworks shaped by the Arizona v. California decree and treaties affecting Mexico–United States water relations.

Infrastructure and Components

The system comprises major features: the Colorado River intake near Lake Havasu City, the Parker Dam bypass, the Hi Line Canal connections, pumping plants like the Deer Valley Pumping Plant, and a 336-mile aqueduct terminating near Tucson, Arizona. Primary civil works reference engineering firms and contractors associated with projects like Glen Canyon Dam and linkage to reservoirs such as Lake Mead and Lake Powell. The CAP interacts with canals operated by entities including the Salt River Project and municipal utilities in Maricopa County, Pima County, and Pinal County. Major pumping stations and hydroelectric facilities follow standards set by organizations like the American Society of Civil Engineers and draw on construction precedents from works like Bureau of Reclamation dams.

Operation and Water Delivery

Operational control involves agencies such as the United States Bureau of Reclamation, Central Arizona Water Conservation District, and municipal water providers like Phoenix Water Services and Tucson Water. Delivery priorities follow allocations set under the Colorado River Compact framework and agreements with tribal nations including the Tohono O'odham Nation and the Gila River Indian Community. Water is apportioned among agricultural districts, municipal suppliers, and industrial users including Intel Corporation facilities and mining operations in the Arizona copper belt. Seasonal management coordinates with regional entities like the Water Users Association, interstate compacts with California and Nevada representatives, and emergency response plans used during droughts involving the Bureau of Indian Affairs and Federal Emergency Management Agency.

Environmental and Ecological Impacts

Environmental assessments invoked statutes such as the National Environmental Policy Act and consultations with agencies like the Environmental Protection Agency. Ecosystem effects have been documented in habitats associated with the Sonoran Desert, riparian corridors like the Salt River, and wetlands in the Colorado River Delta region affected by reduced flows and agreements with Comisión Internacional de Límites y Aguas. Conservation groups including The Nature Conservancy and Sierra Club have litigated or negotiated mitigation measures. Impacts on species listed under the Endangered Species Act prompted studies concerning populations of the Southwestern willow flycatcher and native fish such as the Gila topminnow. Restoration efforts involved partnerships with the Audubon Society and tribal environmental programs administered by the Bureau of Indian Affairs.

Governance and Funding

Governance relies on the Central Arizona Water Conservation District, state agencies like the Arizona Department of Water Resources, and federal statutes administered by the United States Congress and Bureau of Reclamation. Funding combined federal appropriations, bond issues overseen by entities similar to the Arizona Finance Authority, and revenue from water users in districts across Maricopa County, Pinal County, and Pima County. Political advocacy from leaders such as Barry Goldwater and lobbying by utilities like the Salt River Project influenced legislative outcomes. International coordination with Mexico occurred through the International Boundary and Water Commission. Financial pressures during prolonged droughts prompted involvement by agencies such as the U.S. Treasury and potential financing mechanisms used by municipal issuers like the City of Phoenix.

Economic and Social Effects

CAP reshaped economies across regions, enabling expansion of metropolitan areas including Phoenix, Arizona and Tucson, Arizona, supporting agriculture in the Gila River Valley and industrial investment by companies like Freeport-McMoRan and Intel Corporation. Water access altered demographic trends in counties including Maricopa County and Pima County, affecting planning by the Maricopa Association of Governments and social services provided by municipal governments. Tribal economies for nations such as the Gila River Indian Community and Tohono O'odham Nation were affected through settlements and water leasing administered with assistance from the Indian Health Service and tribal enterprises. Tourism and recreation industries linked to reservoirs like Lake Havasu and riverine parks contributed to local revenues tracked by state agencies such as the Arizona Office of Tourism.

Category:Water in Arizona