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4 D. Sediment Transport Measurements. To determine the approximate sediment load during the peak discharge and estimate the sediment load transported by each channel around the spawning bar, two sediment load measurements were taken, at the E-4 and E-5 cross sections. The sediment load measurement consisted of a suspended load sample and a bed load or 'unmeasured zone' load collected with aHelley-Smith sampler. The sediment load samples were collected at the stations where the velocity measurements were collected. Since only two sets of sediment load measurements were collected, a sediment rating curve can not be determined. Suspended load is the sediment transported in suspension or saltation above the river bed. Suspended load samples were collected in June with D-48 sampler using a 3/8 inch nozzle and the applying the equal transit rate method (ETR). At each vertical, the suspended sample bottles were capped after collecting the sample for submittal to the laboratory for sediment concentration by weight and for sediment size distribution. The suspended samples were analyzed by Stewart Environmental Consultants, Inc., Fort Collins, CO. Unfortunately, the samples were not properly analyzed by the lab for either sediment concentration or particle size distribution and the results had to be discarded. The unmeasured zone sediment load consists of the bed load and the suspended sediment not sampled by the suspended sampler (the bottom 3 inches of the flow depth). The unmeasured zone was sampled using aHelley-Smith bed load sampler resting on the bed for 30 seconds. The bed load is the sediment moving either by rolling or creeping in contact with bed. The unmeasured load consists of sediment particles moving in saltation off the bed. The Helley-Smith samples were collected over a variety of bed material and bed forms including sand dunes, bedrock and cobbles. Often, the sampler may plunge through a dune when lifted off the bed or a dune bed form may move toward the sampler during the sampling interval resulting in severe oversampling of the sediment being transported in the unmeasured zone. Oversampling results in large variation in sediment quantities in the sampler bag at different intervals. As a result of the oversampling, the Helley-Smith samples were not a very good measurement of the sediment being transported in the unmeasured zone at these two cross sections. 9