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. , . . IN REPLY REFER TO: United States Department of the Interior BUREAU OF LAND MANAGEMENT Colorado State Office 2850 Youngfield Street Lakewood, Colorado 80215,7093 www.co_blm.gov CO-932 7200 DEe 1 7 2003 ML Dan MelTiman Colorado Water Conservation Board 1313 Sherman Street, Room 721 Denver, Colorado 80203 Dear ML Merriman: The Bureau of Land Management (BLM) is writing this letter to formally communicate its instream flow recommendation for Birdseye Gulch, located in Water Division 2. Location and Land Status. The Birdseye Gulch watershed is located approximately four miles northeast of Leadville. The stream reach that was surveyed begins at the headwaters and runs 3.2 miles downstream to the confluence with the East Fork Arkansas RiveL Approximately 71 % of the reach is owned and managed by BLM, while the remaining 29% is in private ownership. Biological Summary. Fishery surveys indicate that the stream environment is presently in stable condition, and supports a self-sustaining brock trout and cutthroat trout fishery. Water quality, bank stability, cover, food supplies and substrate are good for salmonids. This type of stream environment has steep gradients that typically limit the available pool habitat, and winter icing further limits the amount of available habitat. Accordingly, it i.s important to provide stream flows that protect the limited amount of available habitat if the continued existence of the fishery is to be assured. R2Cross Analysis. BLM's data analysis, coordinated with the Division of Wildlife, indicates that the following flows are required to protect the fi,.hery and natural environment to a reasonable degree: 1_60 cubic feet per second (cfs) is recommended for the May 1 to October 15 high temperature period. This recommendation is driven by the average depth criteria. Meeting the depth criteria is important for insuring that the fish population has access to spawning gravels in a stream that has steep gradients and narrow widths. 0_80 cubic feet per second is recomml:nded for the October 16 to April 30 low temperature period_ BLM staff visited the stream several times during the ice-free season in an attempt to perform R2Cross surveys at flows near 1.0 cfs. However, flows were always significantly above this amount, and BLM was not able to obtain a modeling run in which the winter flow recommendation was inside the confidence interval. Accordingly, BLM recommends