Colorado River Compact - Criticism and Renegotiation

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 16,400,000 acre feet (20.2 km3) per year (641 m³/s). Subsequent tree ring studies, however, have concluded that the long-term average water flow of the Colorado is significantly less. Estimates have included 13,200,000 acre feet (16.3 km3) per year (516 m³/s), 13,500,000 acre feet (16.7 km3) per year (528 m3/s), and 14,300,000 acre feet (17.6 km3) per year (559 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.

In December, 2007, a set of interim guidelines on how to allocate Colorado River water in the event of shortages was signed by the Secretary of the Interior. The guidelines are described as interim because they extend through 2026, and are intended to allow the system operators to gain experience with low-reservoir conditions, while the effect of climate change on the Colorado River's flow undergoes further evaluation. The agreement specifies three levels of shortage conditions, depending on the level of Lake Mead:

• Light shortage. When the surface elevation at Lake Mead is below 1,075 feet (328 m) relative to mean sea level but above 1,050 feet (320 m), the Lower Basin states will receive 7,167,000 acre feet (8.840 km3) per year: 4,400,000 acre feet (5.4 km3) to California, 2,480,000 acre feet (3.06 km3) to Arizona, and 287,000 acre feet (0.354 km3) to Nevada.
• Heavy shortage. When the surface elevation of Lake Mead is below 1,050 feet (320 m) but above 1,025 feet (312 m), 7,083,000 acre feet (8.737 km3) per year will be delivered to the Lower Basin states: 4,400,000 acre feet (5.4 km3) to California, 2,400,000 acre feet (3.0 km3) to Arizona, and 283,000 acre feet (0.349 km3) to Nevada.
• Extreme shortage. The most severe shortage considered in the interim guidelines is when the level of Lake Mead drops below 1,025 feet (312 m), in which event 7,000,000 acre feet (8.6 km3) per year will be delivered to the Lower Basin states: 4,000,000 acre feet (4.9 km3) to California, 2,320,000 acre feet (2.86 km3) to Arizona, and 280,000 acre feet (0.35 km3) to Nevada.

On August 15, 2008, Arizona Senator John McCain called for the compact to be renegotiated. Due to the Senator's position as the Republican Party nominee in the 2008 U.S. Presidential Election and Colorado's swing state status, criticism of the compact may have gained national significance.