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Comments on draft preliminary San Juan River Flow Recommendation July 8, 1998 Page 4 of5 to be most affected and inflows from the Animas will provide a great variability anyway. 10. How are the flow recommendations justified when lower flows at 4-Corners appear to indicate better and more habitat? II. The operating rules state that the minimum baseflow is to be 500 cfs at the Farmington, Shiprock, Four Comers and Bluff gages -- the average minimum to be determined by taking an average of the flows at any two gages, with a minimum release from Navajo of250 cfs. Does the Biology Committee interpret this as a mean daily average allowing for lag times, or only the instantaneous flow at any gage at any time? 12. It needs to be clearly stated that satisfaction of the peak flow criteria will be determined based on the gaged flows at Shiprock. If the peaks at Four Corners and Bluff are also a concern, and subject to the same criteria, this should be clearly stated in the recommendations. If the criteria are applicable to the other gages, what criteria will determine whether the recommendations have been satisfied? 13. The flow durations suggested in the recommendations do not appear consistent with durations suggested by test flow operations at other reservoirs. For example, test flows at Glen Canyon found that a duration of three to four days was more than adequate to move fine sediments. Furthermore, the test flows showed that fine sediments were deposited along channel banks, not simply washed farther down the riverbed. 14. What happens if there is a shortage to the flow recommendations? While the latest thinking is to address this issue project-by-project during individual consultations rather than as part of the flow recommendations, the program still must address this Issue. 15. How can flow recommendations begin to move forward before the technical reports supporting the recommendations are complete? Some of the technical reports will not even be available until June 1998. 16. Colorado is still in the process of exchanging irrigated acreage and hydrologic information with Reclamation. Reclamation is still revising some of its irrigated acreage information based on Colorado's data. Once these revisions have been completed, Colorado would like the opportunity to run that data, along with New Mexico data, through our Colorado River Decision Support System to make sure that Colorado fully understands all the assumptions. Until this is accomplished, Colorado is not prepared to offer support for any flow recommendations. Given the added time needed for the Biologists to complete their supporting studies, there is clearly time for this further refinement and hydrology comparison. Colorado would like it to be clear that we need adequate time to conduct our analysis once Reclamation has provided its revisions, even if that may further delay the final recommendations. 17. The Biology Committee indicated that they would have a draft report available by May I, 1998 for discussion. As of July 8, 1998 no draft report was available and the Coordination Committee meeting has been delayed until mid August. Therefore, public discussion should be rescheduled.