Updated at: 11/20/2012 1:35 PM Timeline of key Colorado River water use events. _ Summer 1869: John Wesley Powell’s expedition navigates the Colorado River and Grand Canyon by boat. _ 1889: International Boundary and Water Commission created between U.S., Mexico. (Spanish: Comisión Internacional de LÃmites y Aguas). _ Nov. 24, 1922: Signing of the Colorado River Compact. "The Law of the River" outlines the rights of northern and southern basins to each use 7.5 million acre feet of water a year. An acre-foot is about enough to serve two homes annually. _ 1928: Boulder Canyon Project Act: Ratifies 1922 compact, authorizes construction of Hoover Dam and lower basin irrigation facilities. California apportioned 4.4 million acre-feet of water a year; Arizona, 2.8 million acre-feet; Nevada 300,000 acre-feet. _ Sept. 30, 1935: Boulder Dam dedication. Later renamed Hoover Dam _ Feb. 3, 1944: Treaty for the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande: U.S. commits 1.5 million acre-feet of Colorado River water annually to Mexico. _ 1948: Upper Colorado River Basin Compact: Apportions 7.5 million acre-feet of upper basin water a year. Colorado gets 51.75 percent; Utah, 23 percent; Wyoming, 14 percent; New Mexico, 11.25 percent. Arizona also gets 50,000 acre-feet of upper basin water annually. _ 1956: Colorado River Storage Project Act: Authorizes construction of Glen Canyon, Flaming Gorge, Navajo and Curecanti dams. _ 1973: Minute 242 of the U.S.-Mexico International Boundary and Water Commission: Requires U.S. to reduce salinity of water delivered to Mexico at Morelos Dam in Baja California near Yuma, Ariz. _ 1974: Colorado River Basin Salinity Control Act: Authorizes desalting and salinity control projects including the Yuma Desalting Plant. _ 2010: Magnitude-7.2 Easter Sunday earthquake damages Mexico irrigation systems, prompts temporary Lake Mead water storage agreement. _ Nov. 20, 2012: Minute 319 of the U.S.-Mexico International Boundary and Water Commission signing in Coronado, Calif. ___ Source: U.S. Bureau of Reclamation, AP research.
By The Associated Press
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