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e e section #2 and the lower terminus was adjusted up from the confluence with West Muddy Creek to the Bell Ranch diversion headgate location. land Status Review Upper Terminus Unnamed Lake Total Length Lower Terminus (miles) Bell Ranch #1 5.2 Land Ownership % Private % Public o % 100 % 100% of the reach is located on federal lands managed by the USFS. Biological Data The USFS has conducted field surveys of the fishery resources on this stream and have found a natural environment that can be preserved. As reported in the letter from USFS to the CWCB "Fishery surveys indicate that the stream environment is presently in stable condition, and supports a self-sustaining native cutthroat and brook trout fishery. Colorado River cutthroat trout in Dyke Creek meet Conservation Population definitions as defined in the Conservation Agreement and Strategy for Colorado River Cutthroat Trout in the States of Colorado, Utah, and Wyoming (April 2001). Conservation Populations are defined as a population of fish with less than 10% introgression (greater than 90% genetically pure). Fish habitat parameters are good for salmonids providing adequate cover and good summer and winter rearing habitat. The stream has an overall stream gradient of approx. 4%. The upper most reach and the segment above the confluence with West Muddy Creek are the steeper segments. The middle several miles of stream are a low gradient alluvial stream set in a wide valley bottom with extensive wetlands and beaver dams. Accordingly, it is important to provide stream flows that protect the limited amount of available habitat if the continued existence of the fishery is to be assured" (See USFS Fish Survey in Appendix B). Flows in Dyke Creek sustain a rich and diverse riparian ecosystem made up of sedge/willow plant communities and the wildlife species that depend upon that habitat type. Field Survey Data USFS staff used the R2Cross methodology to quantify the amount of water required to preserve the natural environment to a reasonable degree. The R2Cross method requires that stream discharge and channel profile data be collected in a riffle stream habitat type. Riffles are most easily visualized, as the stream habitat types that would dry up first should streamflow cease. This type of hydraulic data collection consists of setting up a transect, surveying the stream channel geometry, and measuring the stream discharge. Appendix B contains copies of field data collected for this proposed segment. Biological Flow Recommendation The CWCB staff relied upon the biological expertise of the cooperating agencies to interpret output from the R2Cross data collected to develop the initial, biologic instream flow recommendation. This initial recommendation is designed to address the unique biologic requirements of each stream without regard to water availability. Three instream flow hydraulic - 3 -