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• area' on the northeast side of the river. The site is characterized by riparian vegetation, tamarisks, scrub oak, and cottonwoods. Large natural levees separate most of the site from the Green River. The levee gradually decreases in elevation in the downstream direction. The bottomlands partially fill before a surface connection is established due to seepage from the river. Photos 1 and 2 show the Bonanza Bridge Bottomland for 1996 pre-flooding and with the Green River at 18,500 cfs, respectively. Although this site holds water year round, fish cannot overwinter at this site (P. Nelson, pers. comm.). Horseshoe Bend Bottomland -Located along the left bank of the upstream end of Horseshoe Bend, are 30 acres of floodable bottomland. The Horseshoe Bend (HB) Bottomland is located at river mile 285, five miles downstream of the Bonanza Bridge site. This site is characterized by high natural levees with thick vegetation. A vegetated island exists in the river just below the bottomland location. The vegetation on the levees is comprised of thick scrub oak, tamarisks, and a few Russian olives and large cottonwoods. The bottomland itself has an area of mud flats in its center, surrounded by mostly tamarisks and receives most of its water through seepage as the Green River rises during spring runoff. Currently, the bottomland area completely dries up after runoff season. The Green River drops below a certain level and the seepage connection is lost. Photos 3 and 4 show the Horseshoe Bend Bottomland pre-flooding and with the Green River at 16,000 cfs, respectively. Approximately 1500' upstream of the bottomland, an inlet exists. Water flows into this inlet and travel towards the site and seeps into the ground before making a surface flow connection with the bottomland. Large debris piles from historic floods delineate this path. The Horseshoe Bend site is located approximately 2.5 miles off of Highway 45. However, the road to the site has some stretches which will provide difficulties in hauling large equipment to the site. Stirrup Bottomland -Downstream of the Horseshoe Bend oxbow, the Stirrup (ST) Bottomland provides approximately 34 acres of flooded bottomland. The site is located on river left at river mile 276. High voltage power lines cross the river at the downstream end of the bottomland and an island exists just . downstream of the power line location. The high natural levees are heavily vegetated with scrub oak, tamarisks and a few large cottonwoods. The bottomland currently receives its water through seepage as the Green River uses during runoff season and drains as flows recede. The bottomland has areas dominated by tamarisks on the outer extent with an inner perimeter of reeds and cattails, and some open areas in the deeper center areas of the bottomland. Photos 5 and 6 show the Stirrup Bottomland pre-flooding and with the Green River at 18,500 cfs, respectively. At the downstream end of the bottomland, a natural drainage Swale exists, and is lined by large debris from historic flows. The bottomland is accessed by fairly well maintained dirt roads approximately 15 miles from Bonanza Bridge (9.5 miles of which are dirt roads). Several of the roads in the area were built to access the Stirrup Allotment, oil drilling sites. Baeser Bend Bottomland - At river mile 273, along the left bank, the Baeser Bend (BA) Bottomland provides approximately 60 acres of floodable overbank areas. The bottomland is separated from the river by high, heavily vegetated natural levees. Upland vegetation and several large cottonwoods are located all along the levee, along with tamarisks and more riparian vegetation as the elevation drops towards the river. A large, partially vegetated sandbar extends along the upstream end of Baeser Bend. The bottomland has large open areas in the deeper center sections of the ponds, surrounded by vast areas of thick cattails and reeds, and dense young tamarisks on the outer, shallower sections of the bottomland. In addition, a thick grove of Russian Olives separates the bottomland from the high river levee. The bottomland currently receives its water through seepage as the Green River rises during runoff season and drains as flows recede. Baeser Bend Bottomland may retain enough water over winter to sustain a fish population. Photo 7 shows the Baeser Bend Bottomland, with Green River at 18,000 cfs. By road, the Baeser Bend Bottomland is located approximately 15 miles from the Bonanza Bridge, 9.1 miles of which are the same dirt roads used to access the Stirrup Bottomland. S 'Note that all floodable acreage quantities listed in the descriptions refer to inundation areas corresponding to 24,000 cfs, 5- to 10-year return period based on post-1963 hydrology, of flow in the Green River. The was the discharge proposed as the highest area of inundation of interest in the scope of work. 3