Colorado River too much of the lower basin allotment; in 1944 a compromise was reached in which Arizona would get a firm allocation of , but only if California's allocation was prioritized during drought years. These and nine other decisions, compacts, federal acts and agreements made between 1922 and 1973 form what is now known as the Law of the River. On September 30, 1935, the United States Bureau of Reclamation (USBR) completed Hoover Dam in the Black Canyon of the Colorado River. Behind the dam rose Lake Mead, the largest artificial lake in the U.S., capable of holding more than two
Course of the Colorado River Range – which includes Colorado's highest peak, Mount Elbert – and carves the Black Canyon of the Gunnison before joining the Colorado. In the Grand Valley the Colorado becomes a meandering river in contrast to the steep mountain canyons above Grand Junction. It ranges from wide and from in depth with occasional deeper areas. From there the Colorado turns northwest, past Fruita and entering Ruby Canyon as it approaches the Colorado Plateau. It turns southwest once again just before entering Utah. In Utah the Colorado enters the high desert canyon country of the Colorado Plateau, flowing swiftly southwest through Westwater