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
Steamboats of the Colorado River to make only two trips with forty tons in that time. Trips farther up river to the vicinity of Fort Mohave took at least twice as long. The same difficulty plagued the "Colorado" carrying cargo between the estuary and Arizona City. By the fall of 1863 there was a backlog of twelve hundred tons of freight at Arizona City or in ships anchored in the estuary waiting to be brought up river. Between ten and fifty tons of ore waiting to be brought down to the estuary at each of the landings up river above Arizona City. Some of this