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Show PROBLEMS OF IMPIptfAL VALUSY AND VICINITY. un the west side, above the B line and below the ancient beach line, there is a strip of land about 1^ miles wide extending from the Mexir can boundary north to Superstition Mountain, which, appears from the Strahorn soil survey to be arable land. This tract contains about 14,000 acres net^ and it could be reached with a comparatively low lift (about 50 feet). This area is not included in this estimate as it was nofcincluded in the Gault surveys; however, it should be investigated before the final conclusions are reached as to the area under the All-American Canal. Data for estimates.-The estimate of the cost of the All-Ameriean Canal as outlined in the board report of July 22, 1919, is adopted in this report with appropriate revisions occasioned by the change in canal capacity, due to the revision of theitrrigable area as determined by the Gault and Strahorn surveys. For the extension canal estimates th,e data, including unit costs, prepared by Mr. Gault and appearing in his preliminary reports of November 9 and 16 and also in his field computation books, are generally adopted, with appropriate changes for the revision of acreage as determined by the recently completed soil survey. These data are as follows: Canal capacities.-For long canals a capacity of 1 second-foot to 100 acres, net, is figured at the lower end or at the heads of laterals and an allowance for loss is made at the rate Of 0.5 foot in depth per day over the wetted area. Short canals are figured at a capacity of 1 second-foot to 85 acres, net, at the head of the canal. Velocities.--A nonsilting velocity is planned, ranging from 2.5 to 3 feet per second. Canal side slopes.-For canal construction, side slopes are planned at 2- horizontal to 1 vertical. For canal capacity, on account of the tendency of the silty water to build a berm again'st the constructed slope, one-half horizontal to 1 vertical is figured. Coefficient of friction.-h = 0.0225. . Canal sections. Capacity. Base Depth Tree- width. water. board. Feet. Feet. Feet.. 12- 30 3-5 2.0 30- 45 ' 5- 7 2.5 45- 80 7-8 3.0 80-100 8-10 4.0 Top width banks. 100 to 500 second-feet... 500 to 1,000 second-feet. 1,000 to 2,000 second-feet 2,000 to 3,000 second-feet Feet. 12 12 15 20 Siphons.-The- principal canal structures are reinforced concrete siphons crossing the many large washes. A 9.6-foot diameter barrel is planned, with a capacity of 434 second-feet, and one or more barrels are used, as required. An entrance head of 0.25 foot is al-lowed-in the csnal profile for each siphon, with a fall of 0.1 foot per 100 feet through the structure. Districts.-The project^s divided mto several districts or divisions, as indicated on the accompanying map, Plate XXI, as follows: (a) Imperial irrigation district, comprising the old water-right lands. (b) East mesa gravity, extending from the Mexican boundary on the east side north to the Southern Pacific Railroad. 93715-S. Doc. 142, 67-2------8 |
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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] : |