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The higher discharge is related to the inflow of the White and Duchense Rivers, beginning on April <br />27 and continuing until May 20th. On the recessional limb of the hydrograph, the discharge at the <br />Desolation and Canyonlands level loggers exceed the discharge measured downstream of the White <br />River, revealing the gaining .nature of the river system and some return inflow from bank storage. <br />The Below W11ite River, Desolation Canyon, and Canyonlands level logger discharges are reported <br />' as being higher than the discharge recorded at the Green River from June 4 to June 28, indicating <br />that the Green River stage is probably not calibrated for the shifting stage-discharge relationship <br />' during this period. The Green River discharge should be greater than both the Below White River <br />and Desolation Canyon gages. <br />In Figure 3c, the Desolation level logger, USGS Green River gage and the Canyonlands level <br />logger discharges are plotted separately to show the relationship between the hydrographs <br />at these three sites. The tributary inflow to the Green River from the White River to the confluence <br />of the Colorado River is limited to the Price and San Rafael Rivers and several small tributaries. The <br />Canyonlands hydrograph lags the Below White River hydrograph and after June 10 the data is very <br />consistent. The Canyonlands data from approximately the peak discharge to about June 1 is <br />' somewhat inconsistent because of the shifting of the level logger pipe. In this figure, the Green <br />River gage discharge should be greater than the Desolation discharge but less than the Canyonlands <br />discharge after June 1. The USGS Green River hydrograph is consistently less than both level <br />' loggers. <br />The effects of the White and Duchesne tributary inflow can be seen in Figure 3b. The Below <br />White River level logger mimics the Jensen gage very well, but is approximately 1,000 cfs to 3,000 <br />cfs higher than the Jensen gage. The Below White River, Desolation Canyon and Canyonlands level <br />' logger hydrographs are shown in Figure 3d to illustrate the consistency of the level logger data. The <br />accuracy of this level logger data is result of the selection of stable channel cross sections and <br />consistent rating curves. These sites should be acceptable for fixture level logger installations unless <br />' a major flood event dramatically alters the channel geometry. <br />The level logger data will be applied to the calibration of the flood routing simulation <br />' proposed for the Green River using the FLO-2D model. The model data base is being prepared for <br />application to the Green River from Flaming Gorge to the confluence of the Colorado River. FLO- <br />2D is a two dimensional,. flood routing using a full dynamic wave approximation to the momentum <br />r equation for channel flows. Timing, duration and magnitude will be calibrated in the model using <br />the level logger data. <br />' In the future, the level logger data can be used to analyze the Flaming Gorge releases on the <br />timing, duration and magnitude of flows in the lower Green River system. This information will be <br />' vital to predict timing and duration of flows that open backwater fish habitat, flood larval fsh <br />bottomlands nursery habitat and maintain channel morphology. The level logger data collection <br />program is critical to Habitat Restoration and Channel Monitoring Programs of the Recovery <br />' Implementation Program. This discharge data will enhance our capability to understand and predict <br />water and sediment movement throughout the Green River system. <br />16 <br />