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Instream Flow Recommendation(s) I BLM's flow recommendation is for 5.1 cfs (April I - June 30). 1.7 cfs (July 1 to July 31) & 1.0 cfs (August 1 ~ March 3)) (see BLM Letter in Appendix A). Land Status Review Total Length Land Ownership Upper Terminus Lower Terminus (miles) % Private % Public Raspberry Creek Trapper Creck 2.7 0% 100% This segment is located on 100% public land managed by the BU\-'1 (See attached Figure I). Biological Data The BLM has conducted field surveys of the fishery resources on this stream and have found a natural environment that can be presefwd. As reported for this reach of stream in their September 24. 1999. letter to the CWeB and enclosed fishery surveys (see Fish Sun'cy in Appendix (3). nFishery Surveys indicate that the stream environment is in stable condition and supports a self-sustaining Colorado Rivcr cutthroat trout fishery. Spawning substrate and food availability are good for salmonids. Howcver. cO\'er and pools are limited. underscoring the importancc of adequate nows to maintain sufficiently cool stream temperatures during the summer and fall high temperature period." Field Survey Data BLM and e\VCB staff used the R2CROSS methodology to quantify the amount of water required to preserve the natural em'ironment to a reasonable degree. The R2CROSS method requires that stream discharge and channel profile data be collected in a riffle stream habitat- type. Rimes are most easily visualized. as the stream habitat type Ihat ;.\"Quld dry up first should the streamtlow cease. This type of hydraulic data collection consists of setting up a transect. survcying Ihe stream channel geometry and measuring the stream discharge. Appendix 11 contains copies of the field data collected in regards to this proposed segment. Biological Flow Recommendations The C\VCB staffrclied upon the biological expertise of the cooperating agencies to interpret the output from the R2CROSS data collected to develop the initial. biologic instream now recommendation. This initial recommendation is designed to address the unique biologic requirements of each stream without regard to water availability. Three instream tlow hydraulic parameters. average depth. percent wetted perimeter and average velocity are used to develop biologic instream now recommendations. The CDOW has detemlined that by maintaining these three hydraulic paramelers at adequate levels across rime habitat-types. aquatic habitat in pools and runs will also be maintained for most life stages of fish and aquatic invertebrates (Nehring 1979: Espegren 1996), For this segment of stream. one data set was collected with the results shO\\TI in Table 1 below. Table I shows who collected the data (Party). the date the data was collected (Date). the measured discharge at the time ofthc survey (0). the accuracy range of predicted nows based on \1anning's Equation (240% and 40% of Q). the summer now recommendation based upon meeting 3 of 3 hydraulic criteria and the winter now recommendation based upon 2 of 3 hvdraulic criteria.