Laserfiche WebLink
<br />IJ uJ <br /> <br />In 1989 and 1991 the aquatic habitat of ponions of the Piedra River was surveyed using <br />basinwide techniques; see Table 1. The 1991 survey was done by Forest Service personnel; <br />the 1989 survey was done by contractors under the direction of Forest Service personnel. The <br />main stem of the river within the proposed wilderness is confmed by steep slopes or bedrock <br />walls and has a relatively flat gradient (0.5 - 1.2 %). The channel is comprised primarily of <br />cobble-sized material with some boulders. coarse gravels, and tiner materials. These reaches <br />are dominated by riffles or by a combination of riffles and glides. There are few pools and <br />they typically occur at the base of rock outcrops or are formed by boulder and debris dams. In <br />First Box Canyon, below First Fork, and Second Box Canyon, below Sand Creek., the canyon <br />walls are near-venical rocle outcrop and the stream channel occupies the entire valley bottom. <br />These sections have steeper gradients and have deep pools, cascades, and debris dams. See <br />Figure E. <br /> <br />\lAINSTE:\1 <br /> <br />LOCATION AQUATIC HABITAT RIPARJA.'/ VEGETATION <br />Highway 160 to dominated by shallow riffles; alder/willow with scattered <br />First Box Canvon virtuallv no nools cottonwood on low terraces <br /> steeper gradient; red-osier in rubble along sides of <br />First Box Canyon balanced sequence of canyon <br /> oools/riffles/ll'lides <br />above First Box dominated by gl ides and alder/willow with scattered <br />Canyon to Second riffles cottonwood on low terraces <br />Box Canvon <br />Se1:ond Box Canyon balanced sequence of habitat red-osier in rubble along sides of <br /> types with some deeD oools canvon <br />above Second Box dominated by riffles with alder/willow/red-osier; <br />Canyon to above some deep trench pools cottonwood on floodplains and low <br />Weminuche Creek terraces at and above Sand Creek <br /> <br />Table 1 <br /> <br />Page 8 <br />