Law of the River and Related Legislation
The Colorado River is managed and operated under an international treaty, compacts, federal statutes, regulations, court decisions and decrees, contracts, and other legal documents and agreements that are commonly known as the "Law of the River." This complex body of legal agreements governs the allocation, appropriation, development, exportation and management of the Colorado River among the seven Colorado River Basin states and between the United States and Mexico.
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Law of the River Documents
- Colorado River Compact of 1922 - The foundational agreement governing the Colorado River. Apportions Colorado River water in "perpetuity" between the Upper and Lower Basins.
- Boulder Canyon Project Act of 1928 - This act provided for the necessary Congressional approval of the Colorado River Compact of 1922. Authorized the construction of Hoover Dam and other water storage and delivery facilities in the Lower Basin. Created a comprehensive apportionment among California (4.4 maf), Arizona (2.8 maf), and Nevada (0.3 maf) of the Lower Basin's share of the mainstream waters of the Colorado River.
- California Seven Party Agreement of 1931 - This agreement helped settle the long-standing conflict between California agricultural and municipal interests over Colorado River water priorities. The seven principal claimants reached consensus in the amounts of water to be allocated on an annual basis to each entity.
- Mexican Water Treaty of 1944 - Allots to Mexico, a guaranteed annual quantity of 1.5 million acre feet of the waters of the Colorado River. It also provides for additional or lesser deliveries in identified circumstances.
- Upper Colorado River Basin Compact of 1948 - Apportions the Upper Basin's allocation of Colorado River water among Colorado, New Mexico, Utah, Wyoming, and the portion of Arizona that lies within the Upper Colorado River Basin.
- Colorado River Storage Project Act of 1956 - Provides a comprehensive water resource development plan for the Upper Basin and authorized the construction of Glen Canyon, Flaming Gorge, Navajo and Curecanti dams as well as other participating projects, for multiple purposes.
- Arizona v. California 1964 - Supreme Court's original decree issued in Arizona v. California. This decree addresses allocation of Colorado River water and establishes limits on the United States operation of certain Colorado River reservoirs. The decree has been updated and amended on numerous occasions since 1964. The Supreme Court entered a Consolidated Decree in 2006 which incorporates all applicable provisions of the earlier issued decrees.
- Colorado River Basin Project Act of 1968 - This act authorized construction of a number of water development projects in both the upper and lower Colorado River basins, including the Central Arizona Project (CAP). It also made the priority of the CAP water supply subordinate to California's apportionment in times of shortage, and directed the Secretary to prepare, among other things, long-range operating criteria for the Colorado River reservoir system in consultation with the Colorado River Basin states.
- The Criteria for Coordinated Long-Range Operation of Colorado River Reservoirs of 1970 (amended March 21, 2005) - Addresses the coordinated long-range operation of Colorado River reservoirs in the upper and lower basins pursuant to the Colorado River Basin Project Act of 1968.
- Minute 242 of the U.S. - Mexico International Boundary and Water Commission of 1973 - Addresses actions to reduce the salinity of water being delivered to Mexico at Morelos Dam.
- Colorado River Basin Salinity Control Act of 1974 - Authorized desalting and salinity control projects, including the Yuma Desalting Plant, to improving Colorado River quality.
- Grand Canyon Protection Act of 1992 - Addresses the protection of resources in Grand Canyon National Park and in Glen Canyon National Recreation Area, consistent with and subject to applicable provisions of federal law.
- Endangered Species Act of 1973 - Provided for the conservation of ecosystems upon which threatened and endangered species of fish, wildlife, and plants depend.
- National Environmental Policy Act of 1969 - Established a national policy to promote the enhancement of the environment including the requirement that environmental impact statements be developed for major U.S. federal government actions. Also established the President's Council on Environmental Quality (CEQ).
- National Historic Preservation Act of 1966 - Intended to preserve historical and archaeological sites in the United States of America. The act created the National Register of Historic Places, the list of National Historic Landmarks, and the State Historic Preservation Offices.