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r rose to levels higher than the wetlands. Since the river did not experience overbank flows, the existing bank elevations were sufficiently high enough to preclude flooding of the wetlands. The levee system was not tested in 1993. Bank elevations may have increased over the years as sediment deposition occurred in the dense bank vegetation. Based on preliminary projections in April, bankfull discharge was estimated to range from 19,000 to 24,000 cfs in the wetlands reach of the Green River. Overbank flows did not occur in 1993 with a peak of about 20,200 cfs. An increase in channel conveyance capacity results from bed scour, change in bed form, and submergence of bed roughness which occur with increasingly higher flows. It is now estimated that a discharge of 25,000 to 30,000 cfs is required to exceed the existing river (natural) banks. To reach the wetlands under existing conditions, floodwaters would also have to exceed the additional 1 to 3 ft of levee height. It was observed that the levee had been breached in recent years in several locations, probably during the 1984 estimated flood peak of 40,000 cfs on May 18. The breach of the levee created large scour holes on the east side of the levee. C. Wetlands Restoration. Several facilities would be required to hydraulically connect the wetlands to the river to receive overbank flows. These would include a channel inlet at the river, diversion gate to control or shut off inflow, possible sediment exclusion area and sediment return flow channel, inflow channel from river to wetlands; return flow drainage way to the river, and return flow gate to control water surface elevation in wetlands. Without such facilities the wetland inflow would be uncontrolled and may result in potential long term degradation of the wetland resource values. Possible detrimental impacts of uncontrolled inflow to the wetlands include sediment deposition in the wetlands, sediment deposit in or near the inlet cutting off the inflow, excessive or undesired wetland flooding, inlet erosion and widening, and inability to drain the wetlands if necessary. The most critical aspect of controlling the inflow would be to limit sediment inflow to the wetlands. The Ouray, Utah, Green River wetlands now have a large delta where the inflow channel reaches the wetlands ponds. This delta has filled a significant portion of the original ponded wetlands area (estimated between 10% and 20%). The consequences of sediment deposition in the wetlands is the loss of water storage reducing ponded ~~vater surface area, loss of potential hydraulic head to insure sufficient flow to the area, a potential change in wetland substrate conditions and loss of wetland vegetation due to sediment burial. 33