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basis due to operating emergencies beyond the control of the project operator. A target flow <br />as defined by the Districts, on the other hand, represents a goal which the operator would <br />make best efforts to achieve, but which would not be guaranteed (letter from Gary D. <br />Bachman, Counsel for Central, Washington, D.C., March 20, 1991). According to the <br />Districts, contingencies that might prevent achievement of the established flow level would <br />include water right priorities; evaporation loss, mechanical problems, and irrigation <br />diversions by senior appropriators. <br />Table 2 -1. Winter flows for the Districts' Proposal (source: the staff). <br />Lake McConaughy Predicted May 1 Storage <br />>1.4 MAF >1.2 MAF >1.0 MAF >0.5 MAF <0.5 MAF <br />Overton Flow (cfs) 1,100 N.S. N.S. N.S. N.S. <br />Canal Maintenance Flow (cfs) 1,0001/ 1,000 800 600 N.S. <br />Bypass Flow (cfs) 50 5021 N.S. N.S. N.S. <br />N.S. = none supplied. <br />1/ Minimum diversion at this reservoir level would be 1,600 cfs, exceeding canal maintenance requirements. <br />2/ Except during November when bypass flows would be provided at levels above 1.35 MAF, and during December <br />at levels above 1.3 MAF. <br />Winter Flows (November 1 to March 22). During the winter, Central would operate <br />according to the following priorities: (1) maximizing reservoir fill; (2) maintaining canals; <br />(3) providing flows for bald eagle habitat at Overton and J -2 Return; and (4) producing <br />hydroelectric power. Overton target flows, Central Supply Canal maintenance flows, and <br />Tri- County Diversion Dam bypass flows would be based on predicted May 1 reservoir <br />volumes (Table 2 -1). Hydropower diversions in the Central Supply Canal up to 1,600 cfs <br />would be allowed from November through March when the predicted May 1 reservoir level <br />is between 1.4 and 1.6 million acre feet (MAF). Hydropower diversions up to 2,170 cfs <br />would be allowed December through March when predicted lake levels exceed 1.6 NMR <br />Spring Flows (March 23 to May 10). During the spring, Overton target flows, canal <br />maintenance flows, and Tri - County Diversion Dam bypass flows would be based on actual <br />March 15 reservoir volumes (Table 2 -2). Additionally, to protect walleye spawning and <br />incubation, Central would limit wildlife releases from Lake McConaughy to achieve a <br />1 -foot maximum drawdown during April and May. <br />Summer Flows (May 11 to September 30). Central would provide target flows of 350 cfs at <br />Overton and 50 cfs below the Tri- County Diversion Dam from May 11 to September 30, if <br />reservoir volume is greater than a specified trigger level. The trigger levels would decrease <br />as the irrigation season progresses, and reservoir volume would be calculated on the basis of <br />a 7 -day running average of actual reservoir volume. <br />2 -10 <br />