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TABLE 5 EFFECTS OF FUTURE DEPLETIONS ON RESERVOIR POOL LEVELS Project Normal Elevation Fluctuation (Ft. m.s.l.) Percent of Time Pool is Within Normal Elevation Range 1975 2020 (-5.26 MAFA) Fort Peck, MT Garrison, ND Oahe, SD Big Bend, Fort Randall, and Gavins Point, SD 2226-2246 1830-1850 1596-1616 67 77 70 Relatively 69 67 50 Unaffected Reduced pool elevations are most pronounced for Lake Oahe in South Dakota and Lake Sakakawea in North Dakota, while increases in reservoir fluctuations would be exhibited at these projects as well as at Fort Peck, Montana, and Fort Randall in South Dakota. Big Bend and Gavins Point in South Dakota are primarily flow-through projects with little storage so they would not experience significant operational changes. A combination of summer drawdown and vegetation establishment followed by spring submergence creates good spawning conditions for northern pike. Diversion for this project or other uses would generally improve spawning for northern pike at Fort Peck, Garrison, and Oahe. While northern pike would benefit from the operational changes, other game species would not fare as well. Steady or rising pools during the spring, which are favorable to spawning success, currently occur 3 out of 4 years at Fort Peck and Garrison but would decrease to lout of 5 years by the year 2020 with full High Plains withdrawal. Oahe spawning would be relatively unaffected. Effects on Lake Francis Case Withdrawals at Lake Francis Case are not expected to have any serious effects on terrestrial ecological resources at the reservoir project. Aquatic resources, fisheries in particular, can be adversely A23