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. recommended for the Surmnit County Ski Areas through the Green Mountain EIS were absolute minimum or survival flows, He stated the CDOW "does not like to use the term survival flow in recommending in-stream flows for the CWCB except in extreme circumstances where the balance between preserving the natural environment to a reasonable degree and existing water uses is stressed to the point of survival." Since the Green Mountain EIS recommended flows were survival flows, then the 25% threshold was an absolute maximum impact beyond which the survival ofthe fishery was in question. Analysis ofthe Miller (1993) report (tables 6 to 10) reveals that reductions in flows from 10 cfs to 4 cfs create a loss of 50% of winter habitat types for all species (brown, brook and rainbow trout). For brown trout winter habitat, fry would lose 47%, juvenile would lose 42%, and adult losses would reach 36%. For rainbow trout, the loss of fry, juvenile and adult winter habitat would be 16%, 32%, and 43%, respectively. For brook trout, juvenile and fry habitat curves were not available so only adult winter habitat losses were calculable, and they were 15%. For riffle habitat the losses ranged from highs of 34% for rainbow adult habitat and 32% for brown juvenile habitat to a low of only 6% for rainbows juveniles, For brook trout there was an increase of23% of riffle habitat for adults. This analysis reveals that the 4 cfs flow creates adverse impacts to the fishery in excess oHhe maximum allowed significant threshold of25%. Even under the CDOW conditions for a survival flow, which they use only in "extreme circumstances", the 4 cfs flow would not be recommended as the impacts exceed the 25% threshold. . iii) Chadwick Ecological Consultmlts produced several reports using IFIMiPHABSIM on Snowmass Creek while working for the Aspen Skiing Company during the CWCB hearings and the 404 pennit process in the mid 1990's and now for the SWSD. Chadwick reports from 1992 and 1996 provide some IFIM analysis but he does not provide the data as in the Miller report. These Chadwick reports justify 7 cfs as a valid minimum flow and the basis for the justification is the "habitat bottlenecks" that occur in every Rocky Mountain stream. According to Chadwick, the trout populations in Snowmass Creek are limited by a "bottleneck" that occurs during spring high flows, Using the IFIM data, he shows that there is more Weighted Useab1e Area (WUA) at a 7cfs flow than at the 243 cfs average peak flows. Chadwick cites the work ofMr, Barry Nehring of the Colorado Division ofWildJife to support his theory, This comparison may not be valid within the confines ofthe IFIM model, as the data was not collected within the range of flows near high water. More importantly, the logic appears to be flawed, Chadwick ignores the presence of abundant wetlands that are fed by side channels and support beaver ponds in the upper segment of Snowmass Creek. The lower segment contains the same habitat features although not as abundant. High water does reduce trout habitat, temporarily, but the fish seek refuge in flooded wetlands and side channels, These features are termed refuge habitat. A Corps biologist walked through these wetlands and observed many juvenile trout in the flooded willows along beaver ponds, and also observed adults in the side channels. Refuge habitat is a very common feature in Rocky Mountain streams that experience extreme snowmelt runoff events that reduce habitat. Others document the presence of off-channel or refuge habitat in the Snowmass Creek (Chapman 1996, Walsh and Walsh 1995). Walsh and Walsh (1995) reported the presence of trout fry in the side-channels in August and September of 1995, and 1995 high flow was an extremely high flow event. The presence ofthe fry in 1995 in the side channels not . 7