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One Colorado-River staff gauge (TNC7) was-established approximately 300 m downstream from the Colorado. River bridge on `°`~ highway 191. River level was monitored regularly from early June through October 1993. Data collected was later translated into water surface elevation by date. ,This data is-used, with flow records from the same days recorded at the U.S.G.S. Colorado River gauge at Cisco to develop a stage-discharge relationship for the Moab-site. This relationship is used to create historical stage data from the .Cisco gauge record which dates to 1914. For example,- we know that when water level at 'our-staff gauge was at 3,963. feet elevation, a flow of 40,000 cfs was recorded at the Cisco gauge Thus, any time in the: past that flows of 40,000 cfs-were recorded at Cisco, we estimate that river stage-at Moab was-approximately -3,963 feet. We realize that channel bed morphology changes over time and that-the position and character of the river is not the same as in past years. However, the current river bed is representative of past conditions at least for our purposes. of determining how many years during the period of record (for the Cisco gauge) flows sufficient to create overbank flooding occurred, and of what duration each flood was compared to the -flood of 1993. Stage discharge graphs are shown in. Figures- 3 and 4. The regression for Figure 3 was developed using log transformed elevation-and flow data. The graph shown. in Figure 4 was ; creating-with untransformed data. These graphs can be used to estimate-how often during the period of record the. Colorado River had flows overbank in-the area of our staff gauge.: We have determined that-the. Colorado River goes overbank in this-area at approximately 3-,963 feet elevation,. which requires .today flows of aPProximately 40,000- cfs. 9