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<br />- 2- <br /> <br />the existing outlet works with a new outlet 1 spillway pipe and stilling basin, installation of a new <br />release valve and hand wheel, installation of a new Parshall flume and installation of a siphon. The . <br />rehabilitation of the Reservoir will make operation and administration of the District's plan for <br />augmentation more efficient and reliable. <br /> <br />Due to the high elevation of the Reservoir site, the District commenced the rehabilitation work a few <br />days after closing on the purchase. On August 20, the District opened the outlet valve to empty the <br />Reservoir, releasing water at a rate ranging between 2 and 12 cfs. It has become evident that there <br />are springs in the Reservoir contributing water, which has made the dewatering slower and more <br />difficult. The contractor has installed two siphons to assist with the dewatering, which have been <br />draining water at a rate of 2-4 cfs from the Reservoir. The District has asked the Board to accept the <br />release ofthe entire active storage content of the Reservoir (approximately 400 acre-feet) in lieu of a <br />winter mitigation release later in the year. It is not certain whether the springs will continue to flow <br />into the Reservoir throughout the rehabilitation process, scheduled to be completed by October 15, <br />2005. If these spring flows persist, they could help maintain flows in the Slate River, and also could <br />enable the District to refill Meridian Lake Reservoir more quickly than anticipated. Karen Shirley, <br />manager ofthe District, will be available to update the Board and answer questions at the Board <br />meeting. <br /> <br />The District's Request <br /> <br />Because water released from Meridian Lake Reservoir is the only source of replacement water in the <br />District's plan for augmentation, the District will be unable to replace out-of-priority depletions <br />under the plan during the time the Reservoir is empty for the rehabilitation work. The District . <br />attempted to obtain an alternative source of replacement water for the rehabilitation period, but was <br />unable to do so. <br /> <br />The District has quantified the depletions that it will not be able to replace during rehabilitation of <br />the Reservoir, concluding that the total potential depletions from the wells that would have been <br />augmented by releases from Meridian Lake Reservoir amount to approximately 0.1255 acre-feet per <br />day, which equates to a reduction in stream flow of 0.0633 cfs. As of the date of completion of this <br />merno, flows in the affected Slate River ISF reach were 23 cfs, the decreed amount ofthe ISF. <br /> <br />The Division of Wildlife is in the process ofreviewing this request and will be available at the Board <br />meeting to conunent on and answer questions about the biological aspects of potential reduced flows <br />in the Slate River. <br /> <br />Staff Recommendation <br /> <br />In light of the short time period during which the District will be unable to release replacement water <br />from the Reservoir and the benefits that will be derived from rehabilitating the Reservoir, Staff <br />reconunends that the Board grant the District's request and agree to (1) accept the release of the <br />active storage content of the Reservoir in lieu of a winter mitigation release later in the year and (2) <br />to not place a call for its Slate River instream flow water right during the period when the Reservoir <br />is undergoing rehabilitation. <br /> <br />I <br /> <br />Attachments <br /> <br />Flood Protection. Water Project Planning and Finance. Stream and Lake Protection <br />Water Supply Protection. Conservation Planning <br />