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'" ~ not imply that Interim Flows have produced large numbers of young chub when no such relationship has been established. i;1 !~.I ,. * Cold water conditions in backwaters of the river are not ameliorated sufficiently by more stable flows to enhance survival of larval Humpback chub. * The change from normal fluctuating flows to test flow conditions was believed to be the factor which caused a massive die-off of trout in the Lee's Ferry fishery with a resulting impact on anglers and commercial guides. * The Interim Operating Criteria reduction in maximum permissible water release has caused significant loss in hydropower capacity and resulting economic losses. The reduced maximum permissible release also prevented the rebuilding of beaches up to the previous high water line. ~ , \~ * Backwater, low velocity habitats have silted in during Interim Flows due to the lack of return flows to scour them clean. ~, ~ i;. t- ,,,, <; '" (- ,~ :"J. r' FUTURE UNDER THE PREFERRED ALTERNATIVE ,'. " ) Under the Preferred Alternative, the USBR proposes a course of action without a defined goal. The USBR proposes to further change downstream conditions by altering releases from the dam from those used in Interim Flows. Although not all prefer the new environment created by the dam, the increase in riparian habitat, wildlife, recreation, and reduction in nonnative warm water fish which has occurred after dam construction and under fluctuating flows is generally viewed with support. Although the USBR proposal is merely attempting to make these conditions better, they actually risk making things worse. No defined goals are presented (e.g., 2,000 more acres of riparian habitat, 10,000 more humpback chub, increase of one pound in the average weight of creeled trout, etc.). Without defined goals, scientists will have no way of measuring whether new strategies are succeeding or failing. We have no idea whether the system is capable of supporting new, changed conditions. Thus, we risk making changes merely for change itself and not because of some perceived benefit tied to a defined goal. ....; ';j ". .-.~ ~r; " .Ii~ " .~ !.... , '. ,1 ~ ,. ! "J. " " The USBR proposes to continue the same flow scenario used under Interim Flows but has added a few new elements. The problems created by the use of Interim Flows would continue as earlier described but the additional elements (Common Elements) are likely to cause additional problems downstream. Also, Endangered Fish Research Flows consisting of steady summer flows has recently been J " , 6