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<br />V. A. Sperling, Esq. <br />February 2, 2007 <br />Page 2 <br /> <br />2. The cwes staff memorandum indicates that streamflows used in the <br />calculations are based on "current uses and conditions backcast across historic <br />hydrology." No information is included in the staff memorandum to describe the <br />procedure used in this analysis. It appears that the cwes staff calculations are <br />not strictly based on gage records. <br /> <br />Over-Appropriated - In their reports, both the ewcs and Harris Engineering <br />claim the proposed RICO water right will cause the Animas River to become over- <br />appropriated or water critical with respect to water rights administration. This <br />conclusion, however, does not consider potential calls from the Animas-La Plata Project <br />(ALP). Assuming the ALP can place a call as necessary, the existing 760 ds direct flow <br />water rights for the ALP are capable of placing calls on the Animas River that would <br />cause the river to become water critical. Calls can also occur as a result of the 280 ds <br />capacity of the ALP diversion that is currently under construction. As a result, the <br />Animas River Basin will become over-appropriated and water critical upon completion of <br />the ALP features presently under construction. <br /> <br />HARRIS ENGINEERING REPORT <br /> <br />Hydrologic Calculations - The January 5. 2007 Harris Engineering (Harris) <br />report. Expert Report for Opposers to City of Durango Recreation In-Channel Diversion <br />Water Right Application, Water Division 7, Water Court Case No. 06CW9, notes the <br />Boating Park water rights would be unsatisfied an average of approximately 37 percent <br />of the days and would be unsatisfied 330 days in 2002. It is our opinion Harris has <br />overestimated the frequency in which the proposed RICO flows would not be satisfied. <br />Harris did not base its calculations strictly on the historic Animas River streamflow. but <br />instead relied upon CWCB hydrology that reduces historically available flows. As <br />indicated in our report, City of Durango Boating Park Hydrology Study, Case No. <br />06CW09 (revised September 2006), the RICO water right would not be satisfied an <br />average of 27% of the days and during 277 days in 2002. Our calculations are based on <br />the historic Animas River streamflow at the Boating Park location. <br />