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<br />rMAYNES-~RADFORD~SHPS <br /> <br />ID:303-247-SS27 <br /> <br />FEB 16'96 <br /> <br />9:10 No.003 P.D5 <br /> <br />Keith Rose and Patty Schrader <br />February 15. 1996 <br />Page 4 <br /> <br />6. Top of Page 4: <br /> <br />. . . . to provide the gradual ascending and descending limbs oCthe spring peaks. <br />DuriTIS' thc rcsearch period the water from Navajo Reservoir storage ;~ ~tiH .....:I..hl,;. <br />96 ...",'""L vf II... ...d... 1.....~ tv 1YiIl provide the same shape, timing, and frequency, <br />assuming a low winter flow of approximately 300 cfs. <br /> <br />...... ... <br /> <br />The winter low flow test as required in Element 2 above would require <br />releases from Navajo Dam to be ramped down from 500 cfs to about 300 cfs <br />in more than 6 hours, but less than 24 hours. Flows would not be allowed to <br />fall below 500 cfs in endangered fish habitat, as measured at the Shiprock <br />gage. The 4 month test would allow some lII1 assessment of biological <br />response gUa .,J,,,,...14 b", ..""."l;""o.t""d ;11 G ~ybb"'''tLn,.lIl,-", Lv h... "Gl~d. <br /> <br />Cnmment: It is unclear on what basis the Service is asking for a replication of the four month <br />low flow test. Completion of one low flow tcst is all that is required. If the Coordination <br />Committee of the SJRRIP, based on the recommendations of the Biology Committee, <br />concludes that certain low flows should be part of the Navajo Dam release requirements, in <br />order to produce sufficient storage to allow a high spring release, a low flow regime will then <br />be replicated. <br /> <br />In 1991, it was detennined that the minimum study period necessary <br />to conduct the required studies was approximately 7 years. AllY <br />inability to deliver the f1 ows under the third element of the reasonable <br />and prudent alternative would likely prolong the research period. To <br />date, all flows required to complete the research have not been <br />provided, IIVI IlCL~ ex~ low flows aTld the timing ofthe flows hla <br />been synchronous with the natural peaks of the Animas River _ as <br />requested. <br /> <br />Comment: The Animas River may have as many as three peaks during runoff. Several of the <br />test flow years have spanned these peak flow periods. It is impossible to exactly "match" the <br />Animas River "peak." The Biology Committee, in specifying release patterns seeks to match <br />the Animas River peak as closely as possible. To that extent, the flows have matched the <br />Animas River peak in several years. <br /> <br />7. Page 5: <br /> <br />During the research study period, it was anticipated that Navajo Dam would <br />