New report (5 pp) from the CRS: Responding to Drought in the Colorado River
Basin: Federal and State Efforts.
The Colorado River Basin (Figure 1) covers more than 246,000 square miles in seven U.S. states and Mexico. Basin waters are managed and governed by multiple laws, court decisions, and other documents known collectively as the Law of the River. The Colorado River Compact of 1922 established a framework to apportion water supplies between the river’s Upper and Lower Basins (divided at Lee Ferry, AZ). Each basin was allocated 7.5 million acre-feet (MAF) annually under the compact; an additional 1.5 MAF in annual flows was made available to Mexico under a 1944 treaty. Since the Upper Basin’s waters were developed after the Lower Basin, its apportionments are less than the full amount allowed under the compact and are framed in terms of percentages of available supplies. The Bureau of Reclamation (Reclamation) plays a prominent role in basin water management due to the many federally authorized projects in the basin.