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<br />A limited effort to determine sediment transport characteristics was conducted in the <br />field. This effort consisted of sampling the sediment load at two cross sections during the peak <br />discharge. The suspended sediment samples were incorrectly analyzed by the laboratory. <br />There was insufficient data to construct a sediment rating curve. The following conclusions <br />were drawn on the sediment transport characteristics: <br />• Much of the suspended load is wash load in this reach consisting almost entirely of <br />medium sand sized or smaller sediment. <br />• Most of the medium sand and larger sediment is tranported in waves and bed forms <br />in the unmeasured zone. <br />• The unmeasured zone load was collected with a Helley-Smith sampler in dune bed <br />forms and may be over-estimated by as much as 50%. <br />• The right channel of the spawning bar is transporting only 25 to 30% of the bed load <br />or unmeasured zone load in the river. Nevertheless, the cobble substrate in this <br />channel was buried by 1 to 2 ft of sand which had not been removed by mid-August. <br />B. Prediction of Escalante Wetland Overbank Flows. The Green River in the reach <br />from the E-7 to E-18 flows across a broad open valley of relatively mild slope. The wetlands <br />are located to the east of the river in the vicinity of cross sections E-16 to E-18 and consist of <br />a area of old meander bends that were abandoned as the river straighten. and may have slightly <br />incised. Flooding of the wetlands has been prevented by the creation of an artificial earthen <br />levee along the entire river bank from cross sections E-14.5 to E-18. Confinement of high <br />flows in the channel may have contributed to the potential channel incision in this reach. The <br />levee was breached in 1984 by flows in excess of 40,000 cfs. As was observed during the <br />1993 high flow season, this reach is subjected to large variation in sand storage and removal <br />through the creation of sand bars or thalweg scour. <br />The wetlands water surface area was observed to have decreased during the period from <br />April to June. On June 6 with a river discharge of about 17,000 cfs, the river water surface <br />elevation was surveyed near the wetlands. In addition, the wetlands water surface was <br />surveyed using the E-18 cross section left edge of water surface elevation as a reference. The <br />river water surface elevation at E-18 was 3.25 ft higher than the wetlands water surface <br />elevation. Upstream at E-14.5, the river water surface elevation was 6 ft higher than that in <br />the wetlands. This data shows that during the period from April to June the river water surface <br />32 <br />