Laserfiche WebLink
<br />The principal storage features are Lake Granby, Grand Lake, and Shadow Mountain Reservoir <br />located on the Colorado River near Granby, and Willow Creek Reservoir located on Willow Creek, <br />a tributary to the Colorado River below Lake Granby. Willow Creek Pumping Plant lifts the water <br />175 feet, which then flows by gravity via the Willow Creek Feeder Canal to Lake Granby. Granby <br />Pumping Plant lifts the water from 86 feet to 185 feet from Lake Granby to Granby Pump Canal. <br />The canal conveys the water 1.8 miles to Shadow Mountain Lake, which also intercepts North Fork <br />flows of the Colorado River. Shadow Mountain Lake connects with Grand Lake to make a single <br />body of water from which diversions flow to Adams Tunnel to begin the journey to the eastern <br />slope. <br /> <br />Emerging from Adams Tunnel into the East Portal Reservoir, the water flows across Aspen Creek <br />Valley in a siphon and then under Rams Horn Mountain through a tunnel. At this point, it enters a <br />steel penstock and falls 205 feet to Marys Lake Power Plant. This power plant is located on the <br />west shore of Marys Lake, which provides afterbay and forebay capacity for re-regulating the flow. <br />Prospect Mountain Conduit and Prospect Mountain Tunnel convey the water between Marys Lake <br />and Estes Power Plant, on the shore of Lake Estes. <br /> <br />Lake Estes, formed by Olympus Dam, is located below Estes Power Plant, along the Big Thompson <br />River. The afterbay storage in Lake Estes and the forebay storage in Marys Lake enable the Estes <br />Power Plant to meet daily variations in energy demand. <br /> <br />Water from Lake Estes and the Big Thompson River is conveyed by Olympus Siphon and Tunnel, <br />and Pole Hill Tunnel and Canal, to a penstock through which the water drops 815 feet to Pole Hill <br />Power Plant. The flow is then routed through Pole Hill Power Plant afterbay, Rattlesnake Tunnel, <br />Pinewood Lake, and Bald Mountain Pressure Tunnel, and eventually dropped 1,055 feet through <br />two penstocks to Flatiron Power Plant. This power plant discharges into Flatiron Reservoir, which <br />regulates the water for release to the foothills storage and distribution system. The afterbay storage <br />in Flatiron Reservoir and the forebay storage in Pinewood Lake enable Flatiron Power Plant to <br />meet daily power loads. <br /> <br />Southward, the Flatiron reversible pump/turbine lifts water from Flatiron Reservoir, a maximum of <br />297 feet, and delivers it through Carter Lake Pressure Conduit and Tunnel to Carter Lake. When <br />the flow is reversed, the unit acts as a turbine-generator and produces electrical energy. <br /> <br />The St.Vrain Supply Canal delivers water from Carter Lake to the Little Thompson River, St. Vrain <br />Creek, and Boulder Creek Supply Canal. The latter delivers water to Boulder Creek and Boulder <br />Reservoir. The South Platte Supply Canal, diverting from Boulder Creek, delivers water to the <br />South Platte River. Northward, the Charles Hansen Feeder Canal transports water from Flatiron <br />Reservoir to the Big Thompson River and Horsetooth Reservoir. The canal crosses the Big <br />Thompson River in a siphon above the river and highway. Water from the Big Thompson River <br />can be diverted into the canal by Dille Diversion Dam and utilized for power generation at Big <br />Thompson Power Plant. <br /> <br />Project water deliveries and Big Thompson River water to be returned to the river are dropped <br />through a chute from the feeder canal ahead of the siphon crossing, or are passed through the Big <br />Thompson Power Plant to convert the available head to electrical energy. <br /> <br />5 <br />