Integral to ascertaining the navigability of the Gila River at time of statehood is an understanding of the river's geomorphology. The Gila River has been the topic of several geomorphologic studies that focused on changes in channel position and form through time (e.g., Burkham, 1972; Graf, 1981; Huckleberry, 1993b; Stevens and others, 1975). Although detailed historical descriptions of the Gila River only extend approximately 120 years, within that short interval oftime the river has changed between narrow, meandering and wide, braided conditions (see Leopold and Wolman, 1957 for common channel patterns). Channel changes on the Gila River are driven primarily by changes in the frequency of large floods (Burkham, 1972, Huckleberry, 1993b), however, one cannot ignore the effects of human disturbances (Bahre, 1991). Irrigation diversions, dams, exotic vegetation, and channelization have also undoubtedly affected the hydraulics and hydrology of the channel.