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3 \ In the analysis. we first compared. for the two photo dates. the channel pattern of a reach of stream extending approximately 5 miles upstream and 5 miles downstream of the study site. Changes in location and extent of sand and gravel bars. riffles and channel width due to a difference in discharge or photo scale on the two photo sets were noted. Additional changes in these features were studied along with the field derived information of channel cross-section shape, longitudinal profile and substrate. For each site, a determination of the stability of the channel within this reach was made. For study sites where the channel appears to have changed between photo dates, riparian land use and hydraulic conditions at th~ site were ;nspec~ed. Appendix B contains notes on channel conditions taken during photointer- pretation and a summary of the interpretation and information on flows for the different photo dates. Results The Ouray PHABSIM site on the White River was determined to be unstable between the photo sets. Significant channel changes have occurred in this reach, resulting in a less sinuous channel pattern. This straightening of the lower White River is inter- preted to have occurred as a result of the regulation of flow of the Green River. Reduction of the peak flows in Green River have apparently initiated downcutting and steepening of the bed slope of the White River. Extensive riparian land-use changes have occurred along the Colorado River in the Grand Junction, Colorado area. Gravel mining, bank revetments. road and' bridge relocation are apparent changes between photo sets. Minimal channel pattern changes are apparent for the Walter Walker and Clifton PHABSIM sites between 1954 and 1980. However. floodplain manipulation may have in- fluenced the channel changes noted for the Walter Walker and