Bill Williams River, or Fork
In T. 11 N., R. 12 E. Stream formed by the junction of Big Sandy and Santa Maria rivers. Flows west into Colorado river. Named after Bill Williams. Coues says: "It was first named Rio de San Andres by Onate because he was there on St. Andrews day, Nov. 30 1605." Whipple was the first person to explore it from top to bottom. The claim is made that the name Bill Williams was given it in 1840 by Joseph Walker. Sitgreaves called it that in 1851; it shows on his map of that date, as well as the mountain, marked "sometimes called Williams Fork, it is so called by the trappers." Coues says: "Garces is not to be credited with the actual discovery of this stream. It had been located and named long before." Hodge thinks Walker gave it this name in 1840.
Wheeler says: "Bill Williams Fork at the junction of the Big Colorado is 25 feet wide and 2 feet deep, a clear sparkling stream." On its upper reaches he found beavers, mountain sheep and all kinds of game. In another place Coues says: "it was called and mapped Rio Azul by Sidelmaier in 1744," a name which Coues thinks "was sadly misapplied."
Coues continues: "The precise date of the application of this name Bill Williams Fork has escaped me, but it scarcely antedated the Pacific R. R. survey. I am under the impression that it originated with Joseph R. Walker in about 1840. Sitgreaves mentions it in 1851."
Bancroft says: "Williams Fork, formerly the Santa Maria." Beale speaks of it in his diary October 18, 1857 as "Bill Williams Fork." "Williams," river decision U. S. G. B.