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reported in this study result from a complex interplay of these variables and the results of our cross section analysis provide a basic understanding ofYampa River channel morphology. The inflection points identify threshold flows where there are breaks in the energy dynamics of flow. Rimes have the highest slope and therefore the highest inertial and gravitational forces. Fast currents flowing over large stable substrates creates turbulent or broken flow (Gordon 1992). As depths and velocities are reduced the characteristic turbulent flow of rimes transforms into more laminar flow. This can impact the rime community since these organisms are adapted to experiencing broken flow conditions. An underlining assumption of the inflection point approach is that there is a strong relationship between a stable and predictable environment and stability and integrity of the aquatic community, and this is well supported in the literature (Allen 1995). Since this study is interested in minimum flows during the base flow period, effort was placed on flows typically found between August and March. Inflection points identified in the results, represent maximum changes in slope that are related to the inner part of the channel, that part which typically contains flow in the base flow period. The Montana method for minimum flow identification uses an inflection point based on the entire channel, from grassline to grassline (Leathe and Nelson (1989). The Montana approach would have produced inflection points at much high flows than the inner channel method. For example, it was observed in strata 6 that the channel begins to fill at flows of around 1,200 cfs, and bankfull flow occurs at flows of near 8,000 cfs. Because we focused on the base flow period (flows ranging for 1 to 300 cfs) we feel we identified flows necessary to avoid severe habitat degradation as opposed to flows that maintain rime habitats in fair to good condition. 29