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1)[1 J8,13 DRAFT FINAL DRAIT - 12/19/91 In 1989 and 1991 the aquatic habitat of portions of the Piedra River was surveyed using the basinwide techniques developed by Hankins and Reeves (1988). See Table 1. The main stem of the river within the proposed wilderness is contined by steep slopes or bedrock. walls and has a relatively flat gradient (0.9 - 1.2%). The channel is comprised primarily of cobble-sized material with some boulders. coarse gravels. and finer materials. These reaches are dominated by riffles or by a combination of riffles and glides. There are few pools and they typically occur at the base of rock. outcrops (trench pools) or are formed by boulder and debris dams. In First Box Canyon, below First Fork:, and Second Box Canyon, below Sand Creek. the canyon walls are near-vertical rock outcrop and the stream channel occupies the entire valley bottom. These section bave steeper gradients and have deep pools, cascades. and debris dams. First Fork: and its tributaries lie in relatively confined. valleys and have moderate gradients (1.5 .3CJC.). They are riffle dominated streams with occasional pools and glides. Large woody debris forms many of the pools and provides channel stability and fish cover. The substrate is predominantly cobble with gravel and some boulders. Sand and Weminuche Creeks have both steep, narrow canyons and broad, lower gradient sections. Substrate is quite variable and there are several bedrock sections which have waterfalls and large pools. Sheep and Indian Creeb are steep gradient, intermittent tributaries to the lower reach of the Piedra River. Substrate is primarily boulder and cobble sized material. There are small pools which contain water in most years. LOCATION AQUATIC HABITAT RIPARIA1'l VEGET AnON Highway 160 to dominated by shallow riffles alder/willow First Box Canyon vinuallv no pools some cottonwood on low terraces steeper gradient red-osier in rubble along sides of First Box Canyon balanced sequence of canyon pools/riffies/2Iides above First Box dominated by glides and alder/willow Canyon to Second riffles cottonwood Box Canyon Second Box Canyon balanced sequence of habitat red-osier in rubble along sides of tVDes with some deeo oools canvon above Second Box dominated by riffles with alder/willow/red-osier Canyon to above some deep trench pools some cottonwood on low terraces Weminuche Creek at and above Sand Creek First Fork and riftle dominated alder/willow tributaries pools formed by woody streamside conifer debris Sand and variety of habitat types Weminuche Creeks bedrock sections with alder/willow waterfalls and laree oools Sheep and Indian interminent Creeles small pools hold water most alder/willow years Table I Page 8