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<br />STUDY AREA <br />This study was conducted on the Green River at The Stirrup, Baeser Bend and <br />Above Brennan floodplain wetland depressions. These wetlands are located on the <br /> <br />Green River about 27.0 km south of Vernal, Utah between Rm 273.0 and 268.0 (Rkm <br />432.0 and 444.0)(Figure 1). This section of the Green River is characterized by low <br />gradient flow and extensive floodplain habitat. Tamarisk (Tamarix ramosissima) has <br />~ invaded large areas of shoreline and floodplain habitats throughout this reach. Native <br />vegetation types (willow, Salix spp.; Fremont cottonwood, Populus fremontii; and <br />skunkbush, Rhus trilobata) also occupy abundant areas along shoreline and floodplain <br />~ habitats. <br />Naturally occurring levees deposited along the river margin were breached at <br />each wetland site during the Levee Removal Study to increase the frequency of river- <br />floodplain connection (Birchell et al. 2002, FLO-Engineering 1997 and 1998). Breaches <br />were cut to allow flooding at river flows of 13,000 cfs. However, sedimentation and <br />~ down-cutting at breach locations altered the flows required for flooding at each site. <br />The Stirrup site is a located at Rm 273.0 (Rkm 444.0) and connected with the <br />river at flows near 15,000 cfs during the study (Figures 1 and 2). The breach cut is <br />~ located at the downstream end of the site and measures 146 m long by 6 m wide. For <br />this single downstream breach configuration water rapidly enters the site through the <br />~ breach during filling. After the site fills, water slowly pulses into and out of the site with <br />each river flow fluctuation. About 7.8 ha inundate at flows of 13,000 cfs (FLO- <br /> <br />Engineering 1997 and 1998). Slightly more area would be inundated at flows of 15,000 <br />4 <br /> <br />