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11 becomes a more effective conveyor of discharge at higher stages which results in the nonlinear stage-discharge relationship shown in Figure 5. Discharge was measured from 600 cfs to 19,000 cfs to define the relationship. Velocity was measured with the Price current meter or the Price pygmy meter in all facets of the project. The average velocity for each ten foot cell was taken at the 0.6 depth below the water surface. Several vertical velocity distributions were plotted to check the reliability of 0.6 depth measurement. In several instances velocity measurements were taken at 0.2 and 0.8 depth interval to improve the accuracy of the measurements. Substrate analysis was accomplished with a probe. The composition was verified at low flow by observation of the exposed channel and by walking the cross section at shallow depths. Numerous photographic analyses were made with a calibrated square. These photographs were evaluated with collected surface and subsurface substrate samples at several cross sections on the spawning bar (Photo 1). Cross section profiles were made with a continuous sonar depth chart recorder. The profiles were calibrated by surveying the end points. All cross section profiles in the canyon and at the spawning bar sites were obtained in this manner. Water surface slopes and cross section references points were surveyed. The slopes were measured, where possible, several river widths upstream and downstream. It was impossible to measure water surface slope at several cross sections during peak flow. Twice, during the high discharges near the peak, equipment failures resulted in abandoning the data collection for that particular trip. Of the forty-three sets of sediment samples, forty-two Helley-Smith samples were collected and thirty-nine sets of suspended sediment were separated into fine sediment and sand splits. At river mile 16.5, eight cross sections were set up for hydraulic data collection. One set of data at each cross section was taken in April, three additional sets were taken in July and August. Five cross sections were established at a replicate site, river mile 18.5. These were monitored three times during the recessional limb, just one or two days prior to the measurements at river mile 16.5. Water surface slope, velocity, depth, and substrate data were collected at both sites. This data was reduced and prepared as input to the U.S. Fish and Wildlife Service physical habitat simulation computer model (PHABSIM). Laboratory Analysis The mesh size of Helley-Smith sampler bag is 0.25 mm. When determining the total unmeasured zone load and corresponding size distribution, the particle sizes less than 0.25 mm were first removed from the sample. All samples were dried, weighed and sieved at the CSU Engineering Research Center soils laboratory. The suspended sediment sand splits were similarly dried and weighed. A USGS standard visual accumulation tube was employed to obtain size distribution of each suspended sample.