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Show PROBLEMS OF IMPERIAL VALLEY AND VICINITY. 11 essary to develop the entire foundation of the proposed dam, and this will probably modify its location. Similar information is also necessary for the cofferdam which must precede the main construction, and must be, for temporary work, of a rather substantial character. Results of the borings are shown in the accompanying diagrams and indicate the maximum depth to bedrock of about i35 feet below low-water level. This is regarded as feasible, although the foundation work will of course be difficult and expensive in view of the great volume of the river when in freshet. Various studies have been made on the basis of the information available, and these studies indicate the cost of a dam with flow line at 1,230 feet to be about $45,000,000. This would have a storage capacity of about 21,000,000 acre-feefc. Increased height of dam to provide greater storage can be provided at an additional cost of about $1 per acre-foot for the next 10,000,000 acre-feet. A capacity of 31,000,000 acre-feet would require a flow line at about 1,296 feet above sea level. These figures include preliminary work and the completion of the dam in shape to serve for storage purposes and upon which to install power plants, but do not include any other cost of power development or transmission. A reconnaissance has been made for two possible railroad lines- one approaching from the west and joining the Salt Lake & Los Angeles Railroad near Las Vegas, the other approaching from the north, being a continuation of the branch which runs from Moapa to St. Thomas. A reconnaissance should be made also of a possible connection with the Santa Fe system to the south, with a comparison of the cost and results. THE HIGH LINE CANAL. The construction of a high-line canal connecting Laguna Dam with Imperial Valley was investigated and reported upon by a board representing the State of California, the Imperial irrigation district, and the United States under date of July 22, 1919, and a report was published under the title " Report of the All-American Canal Board. A canal located entirely within the United States from the Colorado River at Laguna Dam into the Imperial Valley, California." Reference is made to that report for the details of such a plan, and its unit estimates of cost are accepted for the purposes of this report. It is necessary, however, to modify acreages and other details in view of the information recently collected. The agricultural lands that it would serve in addition to Imperial irrigation district are given in the following table: Table No. 9.-Irrigable acreages, Imperial Valley. Irrigable lands. Doubtful lands. Total. East Mesa...... .................................................. Acres. 160,000 5,000 72,000 33,000 Acres. 10,000 2,000 63,000 87,000 Acres. 170,000 7,000 Dos Palmas tract ............................................... Coachella Valley ........................................... 135,000 West Mesa ............... 120,000 270,000 162,000 432,000 |
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Original book: [State of Arizona, complainant v. State of California, Palo Verde Irrigation District, Coachella Valley County Water District, Metropolitan Water District of Southern California, City of Los Angeles, California, City of San Diego, California, and County of San Diego, California, defendants, United States of America, State of Nevada, State of New Mexico, State of Utah, interveners] : |