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VII. CONCLUSION The calibration and validation of the SSARR model for the Green River from Flaming Gorge Reservoir to Tia Juana Bottom has been accomplished in several phases. Randy Peterson of the Bureau was responsible for the calibration from Flaming Gorge to Jensen, Utah. The Service was responsible for the calibration from Jensen to Tia Juana Bottom. The work accomplished by the Bureau concentrated on aligning the peaks in terms of timing and magnitude. The theory being that peaks flows are more important to the fish and recreationalists than base flows. Using this criteria, the Bureau was able to calibrate the model so that peaks aligned within 1 hour at Mitten Park and Jensen. Regression statistics were calculated for both locations, the regression R value for Mitten Park was .919 and Jensen was .975. These high R values demonstrate that the timing of the flow routing was very accurate when the 3 hour goal established for calibration. Calculated flows matched observed flows within 7.5 percent at Mitten Park and 3.8 percent at-Jensen over a 48 hour period. Calibration at the Ouray Refuge and Tia Juana Bottom was complicated by intervening diversions and flows. The Bureau's Colorado River System Simulation models demand database estimates that 98,000 acre-feet of water is depleted from the Green River downstream of Jensen, Utah. This causes some problems with calibration at the Ouray Refuge site where calculated flows typically exceed recorded flows by an average of 100 cfs to 200 cfs over a 48 hour period. This discrepancy is partly overcome by Tia Juana Bottom, where additional water is added by the irrigation return flows and the White and Duchesne Rivers. Calibration at the Ouray Refuge was typically off by 9 percent average over a 48 hour period while calibration at Tia Juana Bottom was within 7.2 percent over a similar 48 hour period. The calculated R values for ouray Refuge and Tia Juana Bottom were .897 and .915 respectively. The calibration results were based upon a single flow event (release from Flaming Gorge Reservoir) which was observed and measured at each recorder location for a period of 48 hours. Table 6 displays the relationships described above. Table 6 Percent CFS Regression Location Difference Difference R Value Mitten Park 7.5 164 .919 Jensen 3.8 70 .975 Ouray 8.9 144 .897 Tia Juana Bottom 7.2 185 .915 Verification of the model has been accomplished with each new calibration attempt. Specific field tests of releases for endangered species research work on the Green River have provided further opportunity for validating model results. We now believe the model to be sufficiently accurate with respect to both timing and stage to allow the comparison of hypothetical flow regimes at each location. 20