Colorado River Compact
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The Colorado River Compact is a 1922 agreement among seven U.S. states in the basin of the Colorado River in the American Southwest governing the allocation of the river's water among the parties of the interstate compact. The agreement was signed at a meeting at Bishop's Lodge, near Santa Fe, New Mexico by representatives of the seven states.
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[edit] Provisions
The compact divides the river basin into two areas, the Upper Basin (comprising Colorado, New Mexico, Utah and Wyoming) and the Lower Basin (Nevada, Arizona and California). The compact requires the Upper Basin states to deliver water at a rate of 7.5 million acre feet per year (293 m³/s), averaged over a moving ten-year average. Based on historical rainfall patterns, the amount specified in the compact was assumed to allow a roughly equal division of water between the two regions. The states within each basin were required to divide their 7.4 million acre foot per year (289 m³/s) share allotment among themselves. The compact enabled the widespread irrigation of the Southwest, as well as the subsequent development of state and federal water works projects under the United States Bureau of Reclamation. Such projects included the Hoover Dam and Lake Powell.
The current specific annual allotments in the Lower Basin were established in 1928 as part of the Boulder Canyon Project. They are:
| Upper Basin, 7.5 million acre·ft/year (293 m³/s) total | |||
| Colorado | 51.75% | 3.88 million acre·ft/year (152 m³/s) | |
| Utah | 23.00% | 1.73 million acre·ft/year (68 m³/s) | |
| Wyoming | 14.00% | 1.05 million acre·ft/year (41 m³/s) | |
| New Mexico | 11.25% | 0.84 million acre·ft/year (33 m³/s) | |
| Arizona | 0.70% | 0.05 million acre·ft/year (2.0 m³/s) | |
| Lower Basin, 7.5 million acre·ft/year (293 m³/s) total | |||
| California | 58.70% | 4.40 million acre·ft/year (172 m³/s) | |
| Arizona | 37.30% | 2.80 million acre·ft/year (109 m³/s) | |
| Nevada | 4.00% | 0.30 million acre·ft/year (12 m³/s) | |
[edit] History
The compact was the fruit of several years of negotiations among the states. The seven states had previously formed the League of the Southwest in 1919 to promote development along the river. Two years later in 1921, Congress authorized the states to enter into a compact for allocation of the river resources. The agreement was approved by Congress in 1922, the same year it was signed. As part of the compact, the name of the river was standardized along its length. Previously the portion of the river upstream from its confluence with Green River had been known locally as the "Grand River". The change was opposed by many local residents in Utah and Colorado, and the new name was enforced locally by acts of the state legislatures in both states in the early 1920s.
The agreement was controversial even at the time, however. Arizona, for example, was dissatisfied with its allotment and refused to ratify the agreement until 1944 [1]. The specific allotments were disputed by Arizona until the United States Supreme Court upheld the amount in the 1963 decision in Arizona v. California. The agreement ended many years of dispute, clearing the way for the Central Arizona Project, authorized by Congress in 1968.
[edit] Criticism and renegotiation
In recent years, the compact has become the focus of even sharper criticism, in the wake of a protracted decrease in rainfall in the region. Specifically, the amount of water allocated was based on an expectation that the river's average flow was 16.4 million acre feet per year (641 m³/s). Subsequent tree ring studies, however, have concluded that the long-term average water flow of the Colorado is approximately 13.5 million acre feet per year (528 m³/s). Many analysts have concluded that the compact was negotiated in a period of abnormally high rainfall, and that the recent drought in the region is in fact a return to historically typical patterns. The decrease in rainfall has led to widespread dropping of reservoir levels in the region, in particular at Lake Powell, created by the Glen Canyon Dam in 1963, where the exposure of long-inundated canyons has prompted calls for the deliberate permanent extinction of the reservoir.
As of 2005, the crisis has forced the seven states and the federal government to begin initial steps towards a possible renegotiation of the agreement.
[edit] References
- Lawrence J. MacDonnell et al. (October 1995). "The Law of the Colorado River: Coping with Severe Sustained Drought". Water Resources Bulletin 31: 825-836.
