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PROJECT LOCATION AND DESCRIPTION <br />Allen Lake Reservoir is an off channel reservoir owned and operated by the Left Hand Ditch <br />Company for the purpose of storing irrigation water. The dam is located in Section 13, Township <br />2 North, Range 71 West of the 6th Principle Meridian. The dam is located in Boulder County, <br />Colorado, approximately a tenth of a mile west of Colorado Highway 7. Allen Lake Reservoir <br />receives water from the Lake Ditch and has a storage capacity of 704 acre -feet with a surface area <br />of 35 acres. The dam has a maximum vertical height of 24.4 feet, a crest length of 1525 feet, and <br />a crest width of approximately 8 feet. The upstream face of the dam is sloped at approximately <br />2H: 1V and steeper in some locations due to erosion. The upstream face of the dam has hand <br />placed riprap that is displaced in places due to erosion behind the riprap. The downstream slope <br />of the dam is approximately 2H: 1V. The downstream face contains extensive landscaping <br />associated with the adjacent residential properties. The landscaping includes irrigation systems, <br />terraces, shrubs, and trees. <br />Lake Isabelle is the highest elevation reservoir in the Left Hand Ditch system, and is located in <br />the Indian Peaks Wilderness Area at an elevation of about 11,000 feet. A hard rock tunnel is <br />used to divert water through the mountainside to an outlet work. Lake Isabelle is a glacial lake <br />that was partly enlarged to create a reservoir. At full storage Lake Isabelle stores 550 acre -feet <br />of water. <br />A vicinity map showing the locations of Allen Lake and Lake Isabelle is shown in Figure 1. <br />PROJECT SERVICE AREA <br />The Company service area is roughly located along Left Hand Creek from the foothills of the Front <br />Range east to Niwot, Colorado, Figure 2. A schematic diagram of the Company's ditches and <br />reservoirs is shown in Figure 3. <br />The service area of for the Company includes between 12,000 and 15,000 acres of irrigated farm <br />land in Boulder County, Colorado. The approximate service area boundaries are shown on the <br />map in, Figure 2, which was provided by the Company. <br />Allen Lake and Lake Isabelle — 12.012 <br />Left Hand Ditch Company Page 2 <br />