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ALTERNATIVES EV ALVA TED . Components of the proposed pumping 'station consist of an inlet structure, inlet pipeline, a well structure, pumps. a power source, outlet pipeline, and an outlet structure. In general, the size of the pipe, pumps and the power source is directly proportional to the volume and rate of pumping. However, at the proposed pumping site, labor costs to install the well structure and inlet and outlet pipelines in the soft lake bed form a large percentage of the total project cost, regardless of pipe or structure size. Evaluation of alternatives was I imited to two inlet pipe sizes and pumps were matched to these pipe sizes for maximum volume and efficiency. A single concrete well structure cost estimate was used for all of the alternatives evaluated because of the high proportional cost of excavation to construction. Ultimately, four alternatives were considered with all four alternatives using the same basic concrete well strucrure, two of the alternatives use a 48-inch diameter concrete inlet pipeline, and the other two alternatives use a 60-inch diameter concrete inlet pipeline. The two 48-inch alternatives differ only in their power source. Likewise with the two 60-inch diameter alternatives. Capital construction costs comprise less than half of the annual cost of pumping water from Big Windsor Reservoir back into the Larimer Weld Canal. The remaining costs are energy related and are a major consideration when evaluating alternatives. Electrical power is the most desirable source of energy because of the reliability and low maintenance. To meet the power demands of the large electrical motors, Poudre Valley REA would need to rebuild a section of line and extend new lines from the north to the proposed site. The cost of these lines is approximately $26,000 and would be paid for by WRCC. An additional charge of approximately $12.600 for setting a standard voltage transformer station and meter at the site would be assessed. The cost of the transformer and meter would be nearly offset by a rebate sponsored by Poudre Valley REA and Tri-State G&T. Power lines to the site, the transformer station, and metering are one-time costs. In addition to these costs . Poudre Valley REA will assess a minimum monthly charge. The minimum monthly charge is the greater of: 1. A charge of $1.50 per KV A ofrequired transformer capacity. Two 600 horsepower motors would require a 1500 KV A transformer (a minimum monthly charge of $2,250), and two 300 horsepower motors would require a 750 KV A transfotmer ( a minimum monthly charge of $1.125).- 2. A demand charge of $11.99 per kW of billing demand plus an energy charge of $0.0386 per kWh. The above rates apply to a standard voltage service. If high voltage motors are used Poudre Valley REA would only provide primary metering whereby WRCC would be responsible for purchasing. installing, and maintaining me transformer station. Other billing procedures would be similar except that the demand charge is reduced to $11.44 per kW of billing demand and the energy charge is reduced to $0.0364 per kWh. (Both procedures offer a further reduction for monthly kWh usage in excess of 400,000 kWh). Annual electrical usage rates will vary depending on the amount of water pumped, the number of days per calendar month pumping occurs, and the number of months in which water is pumped. To make a meaningful comparison between two pumping scenarios some assumptions will need to be made to project electrical costs. The following table compares costs for operating a 1200 horsepower pumping system and a 600 horsepower operating system. Assumptions are that motor efficiencies are 90%, pumps will be operated in three calendar months for 19 or 20 days each month, pumps are Floway vertical turbine pumps with electrical demand as specified by the manufacturer. 3 . ,