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<br />e <br /> <br />e <br /> <br />e <br /> <br />stream peak discharges are essential for three reasons: <br />1) they provide the erosive energy required to maintain stream <br />channel dynamics; 2) they erode the grass mat creating mineral <br />soil seed beds and deposit fresh mineral sediment necessary for <br />cottonwood regeneration; and 3) they cause large groundwater <br />table rises under riparian vegetation which recharges soils and <br />provides important summer water for growth. <br />Baseflows in Little Dry creek can be determined by comparing <br />the stage hydrographs for Transect 1 shown in Figure 2, with the <br />stage-discharge table produced by Jay Skinner of the state of <br />Colorado Division of Wildlife. Water levels at sgl from 1 May <br />through September range from 5,414.9 to 5415.2 on all but a few <br />days of record. The mean of 48 records (minus the two days of <br />high flows) is 5,415.07 feet elevation. This translates into a <br />mean baseflow of approximately 4.57 cubic feet per second. <br />I have determined that at least approximately 40 to 60% of <br />this flow, approximately 2.25 cfs, should remain in the stream <br />for riparian vegetation maintenance. In addition, the peak flows <br />must pass untouched, except that the removal of 2.25 cfs of the <br />baseflow would be allowable. <br /> <br />RECOMMENDATIONS <br />1. Peak flows in Little Dry Creek must continue. <br />2. Base flows can be reduced by approximately 40-60 percent <br />without causing appreciable harm to the riparian vegetation. I <br />would suggest a minimum stream flow of approximately 2.25 cfs. <br />3. I suggest that a maximum of 2.25 cfs of water be removed <br />from Little Dry Creek at any time. <br />4. The stream must never go dry, unless it is a natural <br />phenomenon. <br /> <br />17 <br />