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.. \. } would Ulinimi7.e, consistent with tbe Law of tbe River, adverse impacts on downstream environmental and other resources in Glen and Grand Canyons. Under all alternatives considered, tbe annual release volumes are apparently based on the Long Range Operating Criteria and the need to maintain the maximum level of storage in Lake Powell to protect Upper Basin consumptive uses. Monthly volume releasee rates must continue to be based on existing sto.rage levels, monthly target dates, annual release requirements and forecasted inflows. Colorado would be opposed to any changes in the operation of Lake Powell which would release more than 8.23 MAF objective in a minimum release year. (In fact, Colorado continues to object to any implication that 8.23 MAF is the minimum that can be released). Annual releases greater than the minimum can be made only to avoid anticipated spilIs or to equalize storage between Lake Powell and Lake Mead. PREFERRED ALTERNATIVE Reclamation's preferred alternative is the Modified Low Fluctuating Flow Alternative. This alternative seeks to maintain the annual and monthly release volume, based on the Long Range Operating Criteria. Flood frequency reduction would be accomplished by providing additional flood storage space by raising the height of the gates. While these measures appear to adequately protect the Upper Basin's water resources, there are significant negative impacts to power operations and marketing. Some of these negative impacts can be reduced by including modifications to the mllldmum release rates and ramping rates in the operating criteria of the Preferred Alternative. The scientific data suggest mllYirnum release rates can be increased to 25,000 cis and upramp rates increased to 4,000 cis/hI without adversely affecting beaches, fish, riparian habitats and other resources. These measures should be included in the Preferred Alternative of the final EIS. The Preferred Alternative includes further study and research on the impact of reservoir operations on the endangered fish and their habitat. The length of the study period is not specified, but "it is likely that research flows could be completed within 10 years: This research program introduces a great deal of uncertainty into the operation of Glen Canyon Dam. It is imperative that these studies and research flows be conducted under the oversight of the AMWG with full participation by the Basin States. The endangered fish research flows may result in an operation of Lake Powell similar to the Seasonally Adjusted Steady Flow Alternative. While this operation will maintain the annual release volumes of the Preferred Alternative, monthly release volumes and flow rates would change significantly and would have a drastic impact on power operational flexibility and power marketing over the Preferred Alternative. Annual economic and financial costs would increase drastically over the Preferred Alternative. Wholesale power rates would increase by 50.8 % over the No Action Alternative and 24.8 _ %. oyer the Preferred 7