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r - ODU77:) sonic depth information to create a contour map of the lake with which the City's engineering consultants will calculate the current volume and safe yield of the reservoir, and confirm the validity of the storage capacity between elevations 451 and 415. 5. Thursday, June 5, 2008 HDR Engineering gave an initial presentation to the committee. HDR is currently working on population and water use estimates for the next 50 years for Paris and its.wholesale customers, and we anticipate that this information will be discussed at our meeting on July 24th. In addition, HDR is analyzing the current safe yield of Lake Crook and other resources that may be available. We asked HDR to work in conjunction with consultants for Irving so that the committee receives independent information or an independent confirmation of information provided by Irving's consultants, but at the same time avoids duplication of studies where possible. An interesting fact offered by the consultants is that in a typical year with average rainfall, 107 mgd flows into Pat Mayse. 60% of that water flows out over the spillway. Of the remaining 40 %, one -third is used by the City and its wholesale customers, and two- thirds evaporates. Within the projected 100 -year life span of the lake, HDR estimates that a two - year drought will occur five or six times, a three -year drought will occur two to three times, and a five -year drought will occur once. The consultants do not visualize ground water as being a viable source for our needs. 6. On July l Ot' the committee met with representatives of the US Army Corps of Engineers. A number of topics were discussed, including recreational uses of the reservoir, reallocation of water uses in the reservoir, and the manner in which the water level in Pat Mayse is controlled. The Corps advised that the recreational facilities at the lake, in particular the boat ramps, are limited to a minimum lake elevation of 448 msl, and maximum level between 457 to 460. Above the upper elevation access roads, ramps, and camping areas may be under water. Below these elevations the boat ramps are out of the water. Slopes in the area of the boat ramps are gradual, so simply extending the ramps would not be very productive in their opinion. The ramps can be made operational at a lower level but the expense may be significant. The water level in Pat Mayse is "uncontrolled." There is a modified "morning glory" spillway with a crest elevation of 451. When the water level in the reservoir rises above 451 the water flows over the spillway and into Sanders Creek. Below 451 no water is released. The crest of the spillway can possibly be raised. This would require construction of some nature and likely would require congressional authorization. The water level between 451 and 415 is reserved for water supply. Above 451 the storage capacity is for flood control. It is possible, under some circumstances, to reallocate the uses of the storage in the reservoir or to perhaps raise the morning glory spillway to hold additional water in the reservoir. These types of changes would require engineering and 3