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I I II I I I I I I I I I I I I I I I I I These results clearly indicate that the present side channei spillway, and the emergency spillway at the right end of the dam, have a combined capacity to discharge the PMF. The two spillways require minor Improvements to present potential excessive rebuilding costs in the event that they do function. 5.4.3 OUTLET WORKS The exposed upstream outlet gate surfaces were inspected by Lyman Flook on October 26, 1990. The reservoir was at its minimum level. The outlet works appeared to be in good condition. Also present were James Scott of WCC and Sam Boone of the City of Greeley. "7 win/, ' It is concluded that the 33-inch concrete pipe ~.uld.~ended 70 feet to accommodate additional earth fill at the downstream toe of the dam. Since the present outlet works can discharge 165 cubic feet per second of water surface elevation 9,372 (40 gage), the present outlet works can discharge the upper five feet of reservoir capacity of 400 acre-feet in about 30 hours. This compares favorably to the State Engineer's requirement that the upper five feet of storage must be discharged at not less than one foot per day. Extending the present conduit will not reduce the discharge capacity of the present outlet works. The present outlet conduit slopes down steeply 5.67 feet in 320 feet, or 0.0177 feet per foot. The pipe can carry more than 165 cubic feet per second, so the outlet capacity is limited by the size of the outlet works. The present outlet gates appear to be in good condition and will not be replaced. The present outlet works have sufficient capacity to meet downstream water demands. These demands are met even at the restricted reservoir storage levels. The outlet works are more than adequate to maintain restricted storage levels, because of the small size and the drainage area, except in extreme flood conditions.h 5-15