Minimum payment shall not be less than $1.80 per month per kilowatt of the contractor's agreed maximum demand. All rates subject to 10 per cent discount if energy is
delivered and metered at approximately 2,200 volts or more, or 8 per centi f delivered at 2,200 or more volts and metered at a lower voltage.
2 Boise power plant leased to Idaho Power Co., formerly Electric Investment Co.

UNDEVELOPED POWER.

In the following table are listed the power sites more or less completely investigated by the Reclamation Service but which have not been developed. The data given are necessarily, in most cases, only roughly approximate.

ELECTRICAL AND MECHANICAL ENGINEERING.

The electrical and mechanical engineering work of the service is handled by the electrical division of the Denver office. In addition to routine duties, the following work was accomplished by this division during the fiscal year ending June 30, 1918.

Arizona, Salt River project.-Equipment and material was purchased for the Chandler power plant and the Goldfield-Superior transmission line to supply power to the Magma Copper Co. Designs for the needle valve installation at the north tunnel of the Roosevelt Dam were completed and the construction of these valves in the factory of the El Paso Foundry & Machine Co. was followed. The completion of this work was assumed by the water-users' association, to whom the operation and maintenance of the project was turned over on November 1, 1917.

Arizona-California, Yuma project. The designs of the Yuma Valley drainage pumping plant were completed and the project forces completed the construction of the plant to the extent necessary for the starting of the first two units. Preliminary studies and estimates were completed for the construction of the power and pumping plants for the irrigation of the Yuma Mesa.

Colorado, Grand Valley project.-Preliminary studies and estimates were made for the construction of the Price-Stub direct pumping plant to supply a portion of the lands now under the Stub canal of the Mesa County irrigation district.

Idaho, Boise project. Further study was given to the possibility of developing power at the Arrowrock Dam and estimates for several small pumping plants at various points on the project were revised and brought up to date.

Idaho, Minidoka project. Specifications and designs were prepared for the construction of a line and substation for supplying power to the Melcher Mining & Milling Co., 9 miles south of Albion, Idaho. Material and equipment were purchased for the Unity, Riverside, East End, and Central substations. These are small outdoor substations each consisting of a steel tower with line switch, transformers, and metering equipment and are used for supplying power to the distributing circuits of rural electric companies. Preliminary studies were made of an extension of the Minidoka power plant to accommodate two additional generating units, four additional transmission lines, and the necessary auxiliary equipment.

Montana, Huntley project. The Ballantine auxiliary pumping plant, consisting of two 200-horsepower oil engines belted to centrif ugal pumps was designed and all necessary equipment and material purchased. Project forces completed the construction work to the extent necessary for starting both units.

Nebraska-Wyoming, North Platte project. Preliminary designs were completed and detailed designing begun of a needle valve outlet to be connected with the 4 by 6 foot culvert through the Pathfinder Dam. This installation is to consist of a sliding gate mounted below the dam and a needle valve with positive hydraulic control connected immediately below the gate valve.

Preliminary estimates were made for the construction of a hydroelectric plant and necessary transmission lines for supplying power to electric dragline excavators for the canals of the Fort Laramie unit. The plan finally adopted includes the development of power near Lingle, Wyo., under a head of 110 feet, between the Fort Laramie Canal and the North Platte River. The plant will contain two 375-kilowatt generators direct connected to spiral flume turbines. Power at 33,000 volts will be transmitted to points near the excavation work, where outdoor substations will be installed, stepping the

current down to 4,000 volts for transmission to dragline excavators. All materials were purchased and designs for this development were completed. Construction work is in progress by Government forces. Specifications were prepared for the construction by contract of 45 miles of telephone line, but as no satisfactory bids were received the work was undertaken by Government forces.

Nevada, Truckee-Carson project. The operation of the cylinder outlet gates for the Lahontan Dam was considered at a board meeting October 10, 1917, and in cooperation with the civil engineering division designs were worked out for necessary repairs. The required material was purchased and installation nearly completed.

North Dakota, North Dakota pumping project. The matter of operating the project power and pumping system for irrigation during the season of 1919 was under consideration, as was also the extension of the commercial power system. Assistance was given in the appraisal and sale of the equipment from the Buford-Trenton pumping plant, which was definitely abandoned during the year.

New Mexico-Texas, Rio Grande project.-Assistance was given in the purchase, design, and operation of the gasoline engine driven dragline excavators on drainage work on the Rio Grande project. The operation of the Elephant Butte outlet valves was considered at a board meeting June 10, 1918, and plans developed for the improvement of the operation of these valves. A report was prepared on the development of power at the Elephant Butte Dam. The question of power development and construction of pumping plants for the irrigation of lands in the Palomas Valley was also under consideration. Washington, Okanogan project.-Assistance was given in the purchase and installation of an auxiliary plant to relieve the water shortage on the Okanogan project.

Washington, Yakima project, storage unit. The construction of Tieton power plant No. 1 was completed early in the fiscal year. Material and equipment were purchased and designs completed for Tieton power plant No. 2, consisting of two 500-kilowatt units, direct connected to spiral flume turbines. Assistance was given the construction engineer in the arrangement of electrical circuits for the construction plant and in the purchase of numerous items of construction equipment. Preliminary designs were prepared for the outlet works of the Tieton Dam and submitted to a board of engineers December 21, 1917. The plan tentatively adopted includes sliding emergency gates in a chamber in the diversion tunnel above the core wall of the dam and a steel pipe in the tunnel below this point, branching at the lower end to connect with the positive control needle valves discharging into the open canyon below the outlet of the tunnel.

Washington, Yakima project, Sunnyside unit.-The Grandview pumping plant was completed, placed in operation, and tested. Supplemental contract was made with the Platt Iron Works Co. for the correction of the defects in the Outlook pumping units. These units were placed in satisfactory operation at the beginning of the irrigation season and tested shortly thereafter. Supplemental contract was made with the Pelton Water Wheel Co. for improvements to the small pumping unit at the Snipes Mountain plant. Equipment was purchased and designs completed for the Prosser and Spring Creek pumping plants of the Prosser irrigation district.

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