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<br />. <br /> <br />. <br /> <br />. <br /> <br />f <br /> <br />Cooper observed flows from 13-40 cfs in March and April, 2000, during his <br />study of the impacts of the District's diversions on Snowmass Creek. Thus, he was <br />unable to observe the direct effect on the wetlands of dewatering the stream to the 4 <br />cfs "survival flow" level. Dr. Cooper concluded: <br /> <br />Based on the relationship between stage and discharge at this range of <br />flows, a decrease in the flow-of Snowmass Creek from 16 to 4 cfs would <br />result in a drop in stage of only 1-2 inches, if groundwater recharge rates <br />are linearly related to streamflow. In wetland areas connected to the <br />stream, a stage change of this magnitude would most likely result in a <br />similar decrease in the water table level and beaver pond waterlevels. <br />However, our conclusion is based on the assumption that the <br />relationship between river stage and wetland water levels at flows above <br />16 cfs is als 0 valid for flows as low as 4 cfs. If groundwater recharge <br />rates are non-linearly related to streamflow then floodplain water table <br />declines of 2 feet are possible. At some flow between 16 cfs and 0 cfs <br />the rate of groundwater recharge will drop to a rate insufficient to <br />maintain the current groundwater flow systems through the wetlands. <br />At this flow the rate of recharge will drop substantially and our data set <br />and the rating curves and groundwater level correlations that we have <br />developed cannot predict the resultant wetland water tables. A <br />groundwater level decline of more than 1- 2 feet under wetlands during <br />the winter could allow wetland soils to drain, frost to penetrate, wetland <br />plants that have survived in the unfrozen soils of the Snowmass Creek <br />floodplain and young plants could be damaged or killed. In addition, <br />beaver ponds would dry up depriving any resident beavers of access to <br />food caches. <br /> <br />Ex. 19 at ii-iii. <br /> <br />Thus, diversions at the District's structure directly affect downstream wetlands <br />and beaver ponds. Depletions to the 0-4 cfs level could cause a decline in the water <br />table by as much as two feet. <br /> <br />D. Legal Effect of New Information <br /> <br />As is illustrated by section B above, the District failed to establish a <br />biologically-based survival flow as promised in the 1978 agreements. The District <br />had no discernible basis for its statement that the diversion would not significantly <br />affect the fishery. The failure to do so effectively invalidates the Caucus's withdrawal <br />of its opposition to issuance of the original pennit, and provides one of the bases <br />upon which the COIl'S now should reevaluate the pennit conditions. <br /> <br />17 <br />