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. . . Miguel County. The total drainage area of the creek is approximately 5.3 square miles. Mill Creek generally flows in a southerly direction. There are no significant tributaries to Mill Creek within this reach. The subject of this report is a 2.0 mile segment of Mill Creek beginning at its headwaters and extending to the Town of Telluride's Diversion Point (see Figures 1). This segment is located near the Town of Telluride. To date, the staff has received only one recommendation for the segment listed above. That recommendation is discussed below. Instream Flow Recommendation(s) The CD OW has recommended 6.7 cfs for the summer time period and 2.4 cfs for the winter time period. Land Status Review Land Ownershi % Private % Public 10% 90% Upper Terminus Headwaters Total Length (miles) 2.0 Lower Terminus Diversion Point This segment is approximately 90% public land and 10% private land. 100% of the public land is managed by the USFS (See attached Figure 1). Biological Data The CD OW has conducted field surveys of the fishery resources on this stream and have found a natural environment that can be preserved. As reported for this reach of stream in CDOW'S recommendation letter to the CWCB, no fish were collected; this is not to be interpreted in such a manner to say that Mill Creek is incapable of supporting fish. Mill Creek supports a wide variety of aquatic macroinvetebrates indicative of high quality water and it supports a healthy riparian community. The geology of the Telluride area is unique in that the water of many the San Miguel's tributary streams have extremely low conductivity; in other words, the water quality of nearly all of the San Miguel's tributary streams is extremely pure - pure to the point that electro fishing is not possible with standard electro fishing equipment. Fish may exist in these streams but they are not readily sampled with standard electro fishing gear. The CDOW believes that the lower reaches of these streams are used by fish that are residents of the mainstem San Miguel River and are important to the San Miguel's fish community during some periods of the year (i.e. spawning, rearing, and refugia from high flow events). Fish were observed but not captured in lower Mill Creek in 1996. CDOW also believes that the high quality water that is produced by the tributary streams is extremely important to the impaired water quality of the San Miguel River. Mine drainage into the San Miguel River and mill-tailing piles adjacent to the river are currently being cleaned up as a result of comprehensive reclamation effort above the Town of Telluride. Dissolved levels of heavy metals in the San Miguel River continue to be a problem for the river's fishery but conditions are improving; the high quality water from tributary streams such as Mill Creek are vital to the continued improvement of water quality and the San Miguel's fish population. Field Survey Data CDOW and CWCB 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.