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Below Shepard , This site is located on river right at RM 250.6. Below Shepard is a natural terrace that ' was only sampled in 1996. During high flows, water floods an area of thick willows on the outside of a large bend in the river. This site does not retain water after flows recede. Old Charlie Diked This wetland is located at RM 250 on river left, and was sampled in 1997 and 1998. A 100' wide, 5' deep breach was cut in the levee road prior to spring floods in 1997. This cut extends 90 feet into the wetland, creating one of the shortest channels between the river and the ' wetland. At 13,000 cfs, the site backfills to flood an area of 87.2 acres (130 acres when full). Another connection was formed at RM 252.0 by the high flows that occurred in 1997. During high flows, a substantial connection was made and fish were observed moving in and out of the , site. Old Charlie Diked is classified as a terrace and retains water for only a few weeks after river flows recede. Hardstem bulrush, cattails, and other aquatic vegetation become very thick as the water level drops. Several large cottonwood trees serve as rookeries. for cormorants and ' herons within the wetland. Old Charlie Wash , This is the only floodplain wetland site studied that has an inlet/outlet structure in place. ' A low spot in a natural levee upstream from the outlet structure also fills the wetland at flows above 15,000 cfs. Old Charlie Wash is located at RM 249.5 on river left and was sampled in 1997 and 1998 as part of levee removal sampling. During 1995 and 1996 the site was also sampled extensively in a separate study conducted by USFWS, Vernal Field Office (Modde 1997). The flood gate remained open in 1997 while flows were high and then was shut as flows receded in June. However, complete draining of the site did not occur until early August, , because beaver dammed the drainage ditch. In 1998, flood gates were shut immediately after the estimated date of peak flow to entrain fish for a nonnative removal effort. The water control structure at this 105 acre site allows for it to retain water and act as a depression or as a terrace if ' the flood gate is left open. Extensive wetland vegetation exists within the pond including cattail, hardstem bulrush and smartweed. Surrounding dikes are covered with tamarisk and cottonwoods. RIVER REACHES Following 1996, six river reaches were established to help monitor effects that floodplain restoration may have on the river fish community. The reaches are 7 miles long and run contiguously downstream from RM 290.0, just above Bonanza Bridge, to RM 248.0 at the Duchesne River confluence (Figure 2.1). Each reach contains one or more of the 12 floodplain, a ' wetlands. Table 2.1 lists which reach each floodplain is in and gives the beginning and ending river mile for each reach. } 15? 1