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et al. 1987). To aid in the recovery ofthese fishes, the u.s. Fish and Wildlife Service (USFWS), in 1987, initiated the Upper Colorado Recovery Implementation Program (RIP). The program calls for the management of habitat using "...instream flows at certain times, locations, and in certain quantities..." (USFWS 1987) which promote the recovery of these species. As' a part of this program, the Utah Department of Wildlife Resources (UDWR) began work to assess flow requirements for the Colorado pikeminnow in the White River, and identify those existing conditions which may impede the recovery of the species (Lentsch et al. 2000). Much of the work conducted by UDWR focused on the impact of Taylor Draw Dam, which was completed in 1984. Lentsch et al. (2000) identified several probable changes in the annual hydrograph ofthe White River that occurred after the completion of Taylor Draw Dam. They divided the available period of gaging records for the White River near Watson, Utah (station 09306500), into three time periods representing various degrees of human usage ofthe White River. The divisions were the early development period (1923 -- 1945), the middle development period (1946 -- 1978), and the post-Taylor Draw Dam period (1985 -- 1993). However, due to the short record after the completion of the dam (9 years), and the failure to consider discharges between 1979 and'1984 when the Watson gage was not active, the results about the post-dam period were inconclusive. Previous studies on the White River have observed that higher discharges modify habitat more so than baseflow discharges (Chart 1987), and that habitat diversity differs by reach (Miller et al. 1982), but specific flows that maintain or improve habitat were not identified. Our objective in this paper is to augment previous studies of the White River by addressing the question of what discharges are necessary to maintain channel form and 5