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I I. I I I I I I , Ie , I I I I I I ,. I approximately 160 MCM (,130 MAP) would be made from Navajo Reservoir during the winter months in order to conserve storage. Additionally, specific releases will be made from the reservoir in order to study habitat requirements of the endangered fish. Lake PoweD The previous 6 lowest consecutive years of inflow on record (1987-1992) reduced the storage in Lake Powell by 12,089 MCM (9,800 MAF). However, due to a 25 percent exceedance inflow in 1993, it is expected that over 8,688MCM (7,043 MAP) of storage will be gained in the entire Colorado River storage system and that Lake Powell will gain approximately 6,047 MCM (4,902 MAP) of storage. Lake Powell is expected to finish water year 1993 at an elevation of 1116,8 m (3664 feet) and storage of 23,422 MCM (18.987 MAF), about 78 percent of capacity, The reservoir storage is projected to continue to decline through the fall and winter, reaching a seasonal low in April, 1994, at an elevation of 1114.7 m (3657 feet) and 22,394 MCM (18,153 MAP) of storage, During water year 1994, releases greater than the minimum release objective of 10,150 MCM (8,230 MAF) will be made in order to equalize the storage between Lakes Powell and Mead except under the minimum probable inflow scenario. Under the most probable inflow conditions, approximately 10,567 MCM (8.566 MAF) will be released from the reservoir and approximately 2,687 MCM (2.178 MAF) of storage will be gained. Under the probable maximum inflow scenario, approximately 14,538 MCM (11.785 MAP) will be released during the water year. This will include releases of 708.0 m3/s (25,000 cfs) for an extended period of time, With the large gain in storage in 1993, it is estimated that it will take 2 years of average inflow to fill the reservoir. The interim flow restrictions on the daily and hourly releases from Glen Canyon implemented in August, 1991, (shown in Table 3) will continue during water year 1994. These interim flow restrictions are designed to minimize any damage to downstream resources until a Record of Decision is made on the GCDEIS. Specific modifications to the flow restrictions have been proposed for water year 1994 and are the subject of consultation under the Grand Canyon Protection Act of 1992, Suggested modifications include increasing the allowable ascending ramp rate from 70.8 m3/s (2500 cfs) to 113.3 m3/s (4000 cfs) per hour and the allowable maximum flow from 566.4 m3/s (20,000 cfs) to 708.0 m3/s (25,000 cfs), A monitoring program has been implemented to measure the effect of interim flow restrictions on downstream resources. Based on a recommendation from the cooperating agencies of the GCDEIS, a high steady release for research purposes may be scheduled from Glen Canyon Dam for one to two weeks during water year 1994, possibly in early April. The product of the discharge and duration of this research release will not exceed 617 MCM (.500 MAP) in addition to the releases otherwise scheduled for the same one to two weeks period. Total releases dUring this period would exceed powerplant capacity (940,2 m3/s or 33,200 cfs) only if determined implementable from legal and scientific perspectives. If thiS determination is made, consultation will occur. This research release will be designed to facilitate the study of the 11 --'"