Law and Policy

The Colorado River is one of the most legally complex river systems in the world, governed by multiple interstate and international compacts, legal decrees, prior appropriation allocations, and federally reserved water rights for Native Tribes. These pages contain key legal and policy documents, rulings, and articles relating to the Colorado River dating back to the 1920's. There are two sections, the first dedicated to water law and appropriation requirements on the Colorado River mainstem and its tributaries (the "Law of the River"). The other section is dedicated to other legal and policy resources including articles, presentations, and studies. For additional information, visit the main Colorado River Resources pages.

The "Law of the River"  The Legal Foundation of Water Allocation on the Colorado River
(chronological order)

Click here to search these sections on the Colorado River Compact

1922 Colorado River Compact (1922)
This historical document allocated the Colorado among the seven Colorado River Basin states.  Each basin is entitled to 7.5 million acre feet of consumptive use annually and the Lower Basin is given an additional 1 million acre feet in annual consumptive use. In addition, thee compact specifies how water would be allocated to Mexico should a treaty be signed.  Finally, the Upper Basin agreed not to cause the flow at Lee Ferry to drop below 75 million acre feet every 10 running  years.

Colorado River Compact Negotiations transcripts (1922)
These transcripts are from the 27 sessions of negotiations over the Colorado River Compact in 1922.

The Boulder Canyon Project Act of 1928
This act authorized the constuction of the Hoover Dam.  It also allocated the Lower Basin share of 7.5 maf among the Lower Basin states with Arizona entitled to 2.8 maf, California entitled to 4.4 maf, and Nevada entitled to 300,000 af.

1944 Water Treaty with Mexico (1945)
This treaty allocated 1.5 maf from the Colorado River to Mexico every year with the exception of low flow years when Mexico would be reduced proportionally to all other states.

Upper Colorado River Basin Compact of 1948
This compact created the Upper Colorado River Commission and apportioned the Upper Basin's 7.5 maf among the Upper basin states by annual flow percentage, giving Colorado: 51.75 percent, New Mexico: 11.25 percent, Utah 23 percent and Wyoming 14 percent.

The Upper Colorado River Basin Compact (1949)
Hearings before a subcommittee on irrigation and reclamation of the Committee on Public Lands in the House of Representatives

Colorado River Storage Project of 1956
This act authorized the construction of Glen Canyon, Flaming Gorge, Navajo and Curecanti dams

Arizona v. California case Special Master's Report (1960) Part1  Part 2  Part3
This is the report of the special master assigned to this case by the U.S.Supreme Court. 

The Arizona v. California U.S. Supreme Court Decision of 1964
In 1963, the Supreme Court decided a 25-year-old dispute between Arizona and California surrounding whether Colorado River tributary flows from the Gila River constituted Arizona's use of its 2.8 maf annual Colorado River allotment. The Supreme Court rejected California's arguments, ruling that lower basin states can legally appropriate and use tributary flows before the tributary co-mingles with the Colorado River.

The Colorado River Basin Project Act of 1968
This Act authorized construction of water development projects, including the Central Arizona Project (CAP). It also gave California priority over CAP water supply allotments in times of shortage and mandated the development of long-term operating strategies for Colorado River storage reservoirs.

The Colorado River Basin Salinity Control Act of 1974
Authorized desalting and salinity control projects, including the Yuma Desalting Plant, to improve Colorado River quality.

Law of the River page from the U.S. Bureau of Reclamation
This collection of documents apportions the water and regulates the use and management of the Colorado River among the seven basin states and Mexico.

Other Important Legal & Policy Documents & Resources
(reverse chronological order)

Water Resouces Archive at Colorado State University library
The Colorado State University Water Resources Archive is a joint effort of the University Libraries and the Colorado Water Resources Research Institute. Formally begun in 2001, the Archive consists of collections from individuals and organizations that have been instrumental in the development of water resources in Colorado and the West.

Pulwarty, R., Jacobs, K., Dole, R., 2005: The hardest working river: Drought and critical water problems on the Colorado.
In D. Wilhite (ed): Drought and Water Crises: Science, Technology and Management Taylor and Francis Press 249-285

Jacobs, K., and Pulwarty, R., 2004: Climate, science and decision making.
In Lawford, R., et al (eds): Water: Science, Policy and Management. AGU Monograph. AGU Press Washington DC 177-204

Pulwarty, R., 2003: Climate and water in the West: Science, information and decisionmaking.
Water Resources (Update) 124, 4-12

Hard Times on the Colorado River: Drought, Growth, and the Future of the Compact(2005)
Twenty-sixth annual conference at the Natural Resources Law Center in Boulder, Colorado from June 8-10, 2005

Facing Limits on the Colorado River (2005) Presentation by Larry MacDonnell

Correspondence between the Secretary of the Interior and Colorado River Basin states (2005).

Fifty-sixth Annual Report of the Upper Colorado River Commission (September 30, 2004)
This is a report covering the activities of the preceding water year and an estimated budget from that year.

Fifty-seventh Annual Report of the Upper Colorado River Commission (September 30, 2005)
This is a report covering the activities of the preceding water year and an estimated budget from that year.

The Colorado, River of Many Returns:  How conflict, goodwill, and resolution set the course (2004)
Speech by Justice Gregory Hobbs of the Colorado Supreme Court at the Colorado River Water Users Association on December 16, 2004.

Water 2025 plan from the U. S. Department of the Interior
This plan is on preventing crises and conflict in the west is an on-going effort that originated in 2004.

Quantification Settlement Agreement and Interim Surplus Guidelines from the U. S. Department of the Interior

Colorado River Basin Study, by Dale Pontius (1997)
A report for the Western Water Policy Review Advisory Commission.

American Indian Water Rights and the Use of the Colorado River Water (1982) by S.K. Smith
This paper shows that the development of Indian water rights, along with other competing water demands on the Colorado River, will require more compromise than has been exhibited in the past.