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%4 s �golT OF Ty U.S.DEPAUTMENrOF THE INTERIOR P``/1' �( BUREAU OF LAND MANAGEMENT �=� 'A United States Department of the Interior d VJ ' ' BUREAU OF LAND MANAGEMENT 9 Colorado State Office �gRCH 3, I' 2850 Youngfield Street IN REPLY REFER TO Lakewood, Colorado 80215-7093 www.co.blm.gov CO-932 7200 DEC 1 6 2003 Mr.Dan Merriman Colorado Water Conservation Board 1313 Sherman Street,Room 721 Denver,Colorado 80203 Dear Mr.Merriman: The Bureau of Land Management(BLM)is writing this letter to formally communicate its instream flow recommendation for the Little Dolores River,located in Water Division 4. Location and Land Status. The Little Dolores River watershed is located approximately 20 miles southwest of Grand Junction. The stream reach that was surveyed begins at the confluence of Beiser Creek and the Little Dolores River and runs 2.5 miles downstream to the border between BLM lands and private lands. Approximately 70 percent of the reach is owned and managed by BLM,while the remaining 30 percent is in private ownership. Biological Summary. Fishery surveys indicate that the stream environment is presently in stable condition, and supports a self-sustaining brook trout fishery. Channel stability,bank stability,and water quality are good for salmonids. However,limiting factors in this reach include a limited supply of spawning substrates and pools,along with occasional low flows and high stream temperatures. 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. R2Cross Analysis. BLM's data analysis,coordinated with the Division of Wildlife,indicates that the following flows are required to protect the fishery and natural environment to a reasonable degree: • 2.40 cubic feet per second is recommended for the April 1 to October 31 high temperature period. This recommendation is driven by the average depth criteria. Meeting the depth criteria is important for insuring that stream temperatures do not become excessively high during late summer and early fall. • 1.00 cubic feet per second is recommended for the November 1 to March 31 low temperature period. Given the paucity of pools in the lower reaches,maintaining depth during the winter to insure adequate physical habitat is especially important.