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EIS Update - DBO (Continued from Page 4) '. I Specifically, Reclamation has proposed a 3-year study (1995-1997) within the Adaptive Management Program to develop a research design for the experimental flows. During this time, researchers will formulate research objectives, hypotheses, and protocols; develop success criteria; perform a literature search; conduct laboratory and short-term field studies; and collect data. Concurrent with research design development, Reclamation has committed to immediately supporting a peer-reviewed assessment on the risks to the native fish of implementing steady flows. - Representatives of FWS have tentatively accepted this proposal, with a possible reduction in the timetable to 2 years (1995-1996). The two agencies have agreed to let science govern the final decision in an agreement that looks something like the following: Experimental flows will be approved under two conditions: 1) If the risk assessment and scientific data are supportive and adequate research protocols are in place or 2) if, for some reason, the study is not completed on schedule or proves to be inconclusive. The flows will not be approved if the assessment and data indicate that the experiment would be harmful. Reclamation and FWS appear to have come to terms on the question of endangered fish research flows; however, another issue remains to be resolved. The FWS, in the RP A, requires Reclamation to take responsibility for a Little Colorado River (LCR) management plan in order to protect the Grand Canyon's humpback chub population. Reclamation asserts that management of the LCR is not within their jurisdiction. Therefore, a management plan of this sort does not meet the definition of a reasonable and prudent alternative. Reclamation does not intend to include the management plan in the fmal EIS preferred alternative. The issue is still being negotiated, however, and resolution may result in a third modification to the preferred alternative. Selective Withdrawal Operations By: Margaret Matter, Member EIS Team Bureau of Reclamation The presence and operation of Glen Canyon Dam has changed the character of the Colorado River below the dam. Prior to completion of the dam, the river was seasonally warm and sediment-laden. Now, Lake Powell traps heat and sediment. Releases from the dam are cold and clear and the overall downstream flow regime and subsequent ecological responses fluctuate around the water release patterns. Increasing mainstem temperatures is believed to be a key element in the promotion of native fisheries. This article discusses selective withdrawal capabilities at Glen Canyon Dam to enhance downstream temperatures. Humpback Chub and Other Native Fishes Pre-dam records portray the humpback chub as wide ranging in the mainstem of the Colorado River through Glen and Grand Canyons, including stretches of tributaries such as tbe Little Colorado River (LCR). Since construction of the dam, the perpetually cold water drawn from the depths of Lake Powell is released downstream. These releases have caused humpback chub and other native fishes to retreat to warmer river habitat and have inhibited spawning, reduced survival rate of young fish, and reduced the ability for the young native fish to recruit into the adult fishery. One of the remaining population aggregations of humpback chub occurs below the dam in the LCR confluence. Other aggregations have been found in the Grand Canyon in the Middle Granite Gorge and at the mouths of other tributaries such 'as Havasu Creek. The LCR population moves upstream into the LCR to spawn and is the only known recruiting population remaining (Continued on Page 6) 5