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Site 1.3: Site 13 was a deep downsucam chute channel located in the Ouray Wildlife Refuge (RM 255.8). This backwater had an area of 1650 m' and a lDUimam depth of 5.0 Ct. By February 4. an ice jam had <livened water into the dry, high water rh'.""1 wt formed this backwater. 'ThiS <livened water created a deep (06.0 !t). swift (> 2.0 Ct/SCC). side cllanDel ill place or this backwater. On February 25 the jam had deared leaving a backwater III tbe dry. hJ&JI water cI1aJutel, with little cJwige to the habitaL Due to the severely cballging coadltlolls in this habitat in February, is was not considered suitable habitat throughout the winter. Site 8: Sile 8 was a downstream oriented chute cliannellocated below the Jensen Biidge (RM 298.2). This backwater bad an area of 620 m' with a maximum depth of 3.6 ft. Average surlace ice thickness was 1.0!t on February I, decreasing to 0.7 ft by February 22 This backwater was suitable habitat though the entire winter. Site 9: Sile 9 was a long downsueam chule channel located against the shore below the Jensen Bridge (RM 297.2). This backwater had an area of 1220 m' and a maximum depth of 4.0 ft. By February 1. milch of the shallow regions (< 0.5 Ct) had frozen solid, reducing the area of suitable habitat to 610 m'. iOn February 22 similar ice conditions existed, however dissolved oxygen concentrations in the baCk third of tM-backwater were below 3.0 mg/l (range 1.4 to 2.9 mg/l). The combination of free waler loss due to ice formation and habitat exclusion from low D.O. levels reduced useable habitat to approximately SOO m'. Even with wintertime reduction in habitat of more than SO% this area was still sufficiently large to shelter fish during the winter. Site 10: Site 10 was a downsucam chute-channel located above the Bonanza Bridge ~ 295.5). This backwater had an area of 520 m' and a maximum depth of 4.0 ft. By February 1 ~lIabitat had been replaced by a deep. swift side cha.nneL No evidence of the origiaa1 backwater rcDii:ined. Site 11: Site 11 was a large, shallow scour-channel located above the BonallZll Bridge at (RM 292.5). .This backwater had iUl area of 3400 m' with a maximum depth of 1.8 fl. By February 1. this area had a thin ice am:r (llY'Crage 0.3 Ct) which did not significantly reduce babitaL On February 22 this habitat had changed to a shallow side channel, with current velocities of -1.0 fl/SCC. This area was considered unsuitable winter habitaL Site U: Site 12 was a narrow chute channellocatcd above the Bonanza Bridge at RM 293.0. This baclcwater had an area of 360 m' with a maximum depth of 2.2 ft. On February 1. surface Ice was an average . G.6 tt thkk with and average 1.7 Ct of free water. By February 22, warming temperatures had reduced average ice cover to 0.3 ft. This backwater was suitable habitat though the entire winter. 6.2.3 R....... 3 Reach 3 mended from the Bonanza Bridge (RM 290) to Our.lY, UT (RM 248). Two bai:kwatet5 were sampled in Reach 3. River ice conditions indudell large areas of broken surface and jam ice. Mats of jumbled, irrcguIar surface ice. composed of compacted fraziI and dislodged shoreline ice moved into Reach 3 from ReacI1 2. This ice began jamming in CODStricted portioDS of the channel the first week of February. Several jams dammed water, diverting flow inlo dry, high water channels. Two large ice jams, one near the Ouray Refuge Headquarters (RM 255.s to 254.0) &lk1 IDOther al Old Charlie Wash (RM 251.3 to 249.0), pet5isted throughout February breaking up by the !lrst week of March. 14 - - , - ~ j,~-- 1.