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Trinchera Irrigation Company Agenda Item 26b January 19, 2010 (UPDATED February 4, 2010) Page 2 of 5 Smith Reservoir is a 5,000 acre-foot (AF) irrigation water storage reservoir. The reservoir is located about 2 miles south of the Town of Blanca, or approximately 20 miles east of Alamosa. The dam, constructed in 1914, is an earth and rockfill dam. The original dam construction included a concrete core wall with an impervious zone on the upstream side and an upstream slope of 1.5:1. In Apri12009, an intense snow storm accompanied by high easterly winds occurred in the area. This storm caused considerable damage on the upstream slope of the dam due to wave erosion. The erosion resulted in six foot high vertical scarps and large voids between the rockfill. The outlet has existing upstream and downstream gate valves; however, due to operational difficulties with the upstream gate, the Company has controlled the flow with only the downstream valve. This is considered an undesirable mode of operation by the SEO. In addition, the upstream gate leaks because it cannot be completely closed. Due to these concerns, the SEO restricted the dam to a level two feet below the emergency spillway crest (gage height 26.5') on Apri122, 2009. This restriction results in a loss of water storage of approximately 1,100 AF. The Company intends to make the necessary repairs to address the safety concerns in order to restore the reservoir to full capacity rather than risk losing storage. Loan Feasibility Study Jane Devine, Company Office Manager, prepared the Loan Feasibility Study titled "Feasibility of Smith Dam Repairs, November 30, 2009." Technical assistance was provided by Allen Davey, P.E., of Davis Engineering Service, Inc. The study was prepared in accordance with the CWCB guidelines. Trinchera Irrigation Company The Company is a non-profit mutual ditch company incorporated on February 4, 1944, and is managed by a five-member board of directors. There are 43 shareholders and 12,500 shares of stock. A total of 12,396 shares are currently issued. The board has the power to enter into contracts, to cut off water deliveries to shareholders who fail to pay their assessments, and the power to offer stock for sale to pay back assessments. Shareholders must approve the annual assessment at the annual meetings held on the second Tuesday of March. Water Rights Smith Reservoir takes its supply of water from Trinchera Creek, Sangre de Cristo Creek and Spring Creek and their tributaries. The Company's Smith Reservoir decree for 5,000 AF of irrigation water was adjudicated January 4, 1915. In addition, the Company has a 1906 decree for 19,150 AF of irrigation water in Mountain Home Reservoir. On average the Company diverts approximately 26,700 AF annually. Project Description The Company considered three alternatives to restore Smith Reservoir to its full capacity.