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002JJ5 Initial Information Package Williams Fork Hydroelectric Project FERC Project No. 2204 SPILLWAY The spillway is a gated, three-bay, overflow section that allows regulation of Williams Fork Reservoir between elevations 7,803 and 7,811 feet. The spillway section located near the left end of the dam consists of three bays each tenninating in a dentated bucket. Row is contained by exterior training walls projected from the face of the dam and by interior walls between the bucket curves. Three radial gates located at the left, center, and right positions are driven by an electrified hoist. Each gate is 8 feet, 3-inches high by approximately 24-feet long. Each of the spillway gates can be operated at the crest either manually or electrically, as well as by remote control from the powerhouse. A gasoline-powered engine generator provides back-up power to the gate hoists. The spillway gates are protected from possible debris by trashracks installed in front of the gates. The spillway capacity was reviewed pursuant to Part 12 of the FERC regulations. The periodic safety inspection report submitted to the FERC in 1999 found the spillway to have adequate capacity to pass a probable maximum flood (PMF) based on site-specific meteorology and has a flood peak of 16,855 cfs and a 50-hour volume of 14,097 acre-feet. When passing the PMF, the concrete dam has 2.6 feet of freeboard, while the west dike has 4.6 feet of freeboard. INTAKES Two separate intakes, one for the powerhouse penstock and one for the river outlet works, are used at the Williams Fork Dam. A reinforced concrete penstock intake for the powerhouse is located on the face of the dam, 115-feet (35 meters) below the maximum water surface elevation (7,811 MSL), and protected by steel, vertical-bar, multi-panel trashracks. A 7-foot by 5-foot fixed wheel penstock gate releases water into a 66-inch diameter steel penstock that extends from the intake down to the powerhouse. A 66-inch butterfly valve is scheduled for installation in 2003 on the penstock just upstream of the powerhouse. The fixed wheel gate is hydraulically operated from the crest of the dam. The butterfly valve is electrically actuated and locally operated. The river outlet works intake, also on the face of the dam, is protected by a steel vertical-bar trashrack and is provided with a vertically positioned slide gate. The gate is located at the bottom of the reservoir at elevation 7,635 MSL or approximately 175-feet (53 meters) in depth. This intake is normally open but can be manually closed from a gate lift platform on the face of the dam only when the reservoir elevation is below 7,705 feet. A 54-inch diameter steel embedded pipe conveys water to the outlet works 12 .. I I I