To the mesa and other outside lands: Total____ $760,000 1,501, 606 9, 568, 827 Total estimated cost chargeable to Imperial Valley of an all- Canal construction chargeable to power: One-third of cost to Araz, one-third of $4,097,401 (page 19, Gross construction cost chargeable to power: Estimated cost of power plants (page 27, engineer's report) __ Total Yuma project will be charged for an interest in power: Total_. All-American canal, 6,000 second-feet capacity: Estimated total cost of canal construction, including the cost of the right to connect with Laguna Dam, but not including the cost of power development (page 24, engineer's report) $11, 830, 433 29, 576, 082 1, 365, 800 4, 508, 690 1, 365, 800 5,874, 490 910, 534 754, 676 1, 665, 210 24, 304, 048 Charge Yuma project with one-third of $3,549,626 (page 25, engineer's report). 1, 183, 209 Charge Imperial irrigation district with 2, 120, 839 Net canal construction, cost Estimated cost of power plants (page 27, engineer's report). Charge Yuma project with 40 per cent of $1,886,690 (page 28, engineer's report). Charge to Imperial irrigation district_____ 1, 600, 000 21, 520, 839 4, 508, 690 754, 676 3,754, 014 Total estimated cost chargeable to Imperial irrigation district of an allAmerican canal with a capacity of 6,000 second-feet, including power plants and including cost of the right to connect with the Laguna Dam, but not including $1,937,885 to be charged to the Yuma project as follows: Right to connect with Laguna Dam. Part cost of power plants_. Part net canal construction cost Total_. Canal construction cost chargeable to power: One-half of cost to Araz, one-half of $3,549,626 (page 25, en Gross construction cost chargeable to power: $1,600,000 3,754, 014 21, 520, 839 26, 874, 853 gineer's report)... 1, 774, 813 Estimated cost of power plants (page 27, engineer's report) – 4, 508, 690 1, 774, 813 Total_ 6, 283, 503 Yuma project will be charged for an interest in power (6,000 second-foot canal): Part of canal construction cost to Araz, as above_. Total. 1, 183, 209 754, 676 1,937, 885 Connection of Imperial canal with the Laguna Dam (considered Estimated cost of canal construction (page 29, engineer's re- Charge Yuma project with one-third of $3,549,626 (page 25, Charge Imperial district with. Right to connect with Laguna Dam_. Net canal construction cost to be charged to Imperial irriga- Estimated cost of power plant (page 28, engineer's report). Charge Imperial irrigation district with 60 per cent thereof___ $7,039, 041 1, 183, 209 5,855, 832 1, 600, 000 4, 255, 832 1,886, 690 754, 676 1, 132, 014 The estimated cost chargeable to Imperial irrigation district for the construction of a connection with the Laguna Dam, at a capacity of 6,000 secondfeet, including a power plant at Pilot Knob, but not including $1,937,885 chargeable to the Yuma project, nor $1,600,000 for the right to connect with Laguna Dam is therefore: Part net estimated cost of canal construction, as above_- Total Canal construction cost chargeable to power: $4, 255, 832 1, 132, 014 5, 387,846 Gross construction cost chargeable to power: One-half cost to Araz, one-half of $3,549,626 (page 25, engineer's report). 1,774, 813 Estimated cost of power plant at Pilot Knob (page 28, engineer's report) 1,886, 690 Part of canal construction cost, as above_. 1,774, 813 Total_ 3,661, 503 Yuma project will be charged for an interest in power: 1, 183, 209 754, 676 Part canal construction cost to Araz, as above--- Total_ 1,937, 885 Power should be held available for the requirements of the Yuma project and the Imperial irrigation district and any organization for the irrigation of mesa and other lands. Power thus required should be paid for at cost plus 10 per cent. Any power in excess of such requirements should be treated as commercial power and sold. The interest of the Yuma project should be protected in the amount of power for which a construction charge is placed against the project, and if this power be not generated at or near Araz it should be transmitted back to that point without transmission cost to the Yuma project. The participation in profits from power sales should be made proportional to the relative investments in the Imperial Valley. For a high-line canal project to the Imperial Valley some water from storage should be made available. This can best be accomplished if the United States will undertake the construction of storage reservoirs on the Colorado River from which water could be made available for power and irrigation at rates which would cover cost. Any such storage on a large scale would also have some beneficial effect in reducing the peak of the flood discharge in the lower river, thereby cutting down the flood menace to the submersible lands-in particular to those of the delta region and the Imperial Valley. Respectfully submitted. W. W. SCHLECHT. C. E. GRUNSKY. [Report of Porter J. Preston, engineer in charge of surveys and examinations, Dec. 7, 1918.] To: The Board of Engineers, All-American Canal. 1. INTRODUCTION. (a) A contract was entered into by the Secretary of the Interior and the directors of the Imperial irrigation district on February 16. 1918, for a complete investigation, survey, and cost estimate of an all-American canal from Laguna Dam, Ariz.-Calif., into the Imperial Valley." The contract further provides that " in order to determine the possibility and feasibility of carrying an adequate supply of water for the irrigation of arid lands in the Imperial Valley; that such surveys shall be made in sufficient detail so that the character and cost of development shall be shown"; such surveys shall also investigate the ways and means by which power may be developed as an incident to the construction of such irrigation works and the value and possible uses thereof." (b) Under this contract a study of the available data was made in the Yuma reclamation office, and early in March a survey was commenced. (c) Frequent meetings and conferences have been held with the board and individual members of the board, from time to time, and their counsel and advice, aside from their official duties under the contract, have been of material assistance in the work of making the surveys, and the preparation of this estimate. 2. PURPOSE OF PRELIMINARY REPORT. (a) Under date of October 23, 1918, the directors of the Imperial irrigation district entered into a contract with the Secretary of the Interior for a connection with Luguna Dam and the construction of an all-American canal and appurtenant structures, based on the surveys and investigations covered by the contract under which these investigations are being made. (b) The contract of October 23, 1918, provides for the ratification of the contract on or before six months from the date of signing the same. The Imperial irrigation district now desires to submit the question of the ratification of the contract of October 23, 1918, to a vote of the people at an early date. The directors have requested that a preliminary report be made of the estimated cost of connecting with Luguna Dam and constructing the all-American canal, in order that the voters in the district may have knowledge of the cost of the project before voting upon the ratification of said contract. Under the circumstances it has been deemed best to furnish the information desired at this time in a preliminary report. There are some features of the project that require further investigation and study, but these will not materially change the ultimate estimated cost of the project. 3. EARLIER SURVEYS. (a) Several surveys and estimates have heretofore been made, for the purpose of diverting water at Laguna Dam into the Imperial Valley and onto the mesa lands, by what has been termed a high-line canal. These surveys either followed along the route of or contemplated the enlargement of the present Yuma Main Canal from Laguna Dam to Siphon Drop, and thence along the base of the hills bordering the valley from this latter point to the Southern Pacific main line track. From this point the surveys followed the right bank of the Colorado River, generally parallel therewith and but a short distance from the river bank, to a point near the international boundary line. From this latter point the plan followed by the several surveys have differed to some extent, and are described below more in detail. (b) In 1903 and 1904 the United States Geological Survey made a topographical survey of the Yuma project on the California side of the river, extending the topography to the international boundary, and thence westerly for about 2 miles, covering a strip along and parallel with the boundary and about 500 feet in width. (c) In 1908 the Reclamation Service made a topographic survey of the greater portion of the mesa east of the present Imperial East High-Line Canal as far north as the Southern Pacific Railroad. At this time some preliminary lines were run for a high-line canal south of the sand hills through Mexican territory. (d) In 1913 the Imperial irrigation district made a preliminary survey for an all-American aqueduct of a capacity of about 3,667 second-feet through the sand hills. This survey followed along and parallel with the international boundary from a point just west of the Hanlon Heading to a point near the present East High-Line Canal. (e) In 1916 and 1917 the Imperial-Laguna Water Co. made surveys for an all-American canal along practically the same route followed by the Imperial irrigation district in 1913, except it only extended westerly to a point where the msea lands could be served. The early plans of this company contemplated a canal of 1,865 second-feet through the sand hills. Later the company planned a larger canal, but of a much less capacity than the canal here planned. (f) The data and maps of these different surveys were available and have been made use of in making the surveys and estimates. 4. SURVEYS. (a) In 1917 a survey was made by the Reclamation Service for a power canal from Siphon Drop to a proposed power site near Araz. Very careful and complete topography had been taken over this section. The year prior cross sections had been taken on the main Yuma Canal from Laguna Dam to Siphon Drop. It was found that we could use all of this work, and therefore the survey was taken up at the end of the proposed power canal near Araz and extended southwesterly to a point on the east side of Pilot Knob, where we found it would be necessary to either cut or tunnel through a narrow rock spur of Pilot Knob for 800 feet in order to avoid interfering with the quarry of the Imperial irrigation district. From this point the line continues in the same general course to a point 400 feet north of the international boundary, and thence parallels the boundary to a point well within the blow-sand area. From this point the line runs to the northwest, keeping well on the mesa floor among small sand dunes not exceeding 12 or 15 feet in height. At a point about 2 miles north of the international boundary the line takes a southwesterly course through an open mesa for more than a mile, and then again swings to the northwest over a high blow sand ridge 3,000 feet across, into what is locally known as Government Gap. From the western end of Government Gap the line takes a southwesterly course, crossing two main sand ridges which total about 13 miles to reach the mesa on the west of the blow-sand hills; thence on the same general course until it reaches a point 400 feet north of the boundary line; thence along the boundary to monument No. 213, where the line runs somewhat north of the boundary, keeping generally a westerly course in order to take advantage of the topography of the ground. As the line nears the East Side High-Line Canal it again approaches the boundary and follows along it to the west side main except for a detour in order to get around the city of Calexico and to obtain a better crossing of New River. (b) Through the blow-sand area two alternate routes were surveyed, one along the boundary, which is about 1 miles shorter than the line above described, but containing 1,800,000 cubic yards more excavation, and the other to the north of the adopted line and being for the purpose of avoiding the first big sand ridge described above. This latter line is nearly a half mile longer and contains 200,000 cubic yards less excavation. (c) Topography was completed and extended on the section south of Pilot Knob, and a strip of topography 2,000 feet in width was taken on the lines through the sand hills. Additional topography was taken at Laguna Dam, along the Southern Pacific tracks near Araz, Alamo River, and New River crossings. (d) All the topography taken and available was plotted on a scale of 400 feet to the inch. This is shown on 37 sheets, which are on file in the Yuma office. A profile of the canal from Siphon Drop to the West Side Canal on a scale of 500 feet to the inch is also on file in the Yuma office. 5. IRRIGABLE ACREAGE. (a) The irrigable acreage of the Imperial irrigation district now within the district boundaries is about 515,000 acres, all of which could be reached by gravity through an all-American canal, with the exception of two or three sections near the international boundary west of New River, upon which it will be necessary to pump the water. The West Side Main Canal can be made to serve another possible 40,000 acres. (b) In the East Side mesa district there is estimated to be 140,000 acres, and to the north of the Southern Pacific Railroad, east and north of the Salton Sea, including the Coachella Valley, there is another 200,000 acres, making a total of 895,000 acres that can be served by a gravity system. (c) In consultation with the Board of Engineers it was decided to adopt 900,000 acres as the basis upon which to make the estimates. 6. WATER DUTY. (a) With as large an acreage as it is here contemplated to serve, and the fact that a considerable portion of the irrigable acreage has been under irrigation for some years, it was deemed that a diversion duty of 1 cubic foot to 100 acres was sufficient. (b) The losses in the canals are not anticipated to be excessive after they are thoroughly seasoned. It is estimated that there will be delivered to the land 75 per cent of the amount diverted. 6a. CANAL SECTIONS AND CAPACITIES. (a) With the above duty, 900,000 acres will require a diversion at Laguna Dam of 9,000 second-feet in addition to the amount required for the Yuma project of 1,600 second-feet or a total of 10,600 second-feet from Laguna Dam to Siphon Drop. (b) All the larger sections of the canals were designed to give a velocity of 3.5 feet per second when running full and 2.5 feet per second or better when running at half capacity. (c) Below are given some of the dimensions of principal sections of the canal from Laguna Dam to the West Side main canal. The types of the cross sections are shown on the profile. These are marked "sections" and numbered both on the "section" and on the profile to which that "section applies. 1. The canal from Laguna Dam to Siphon Drop will have a bottom width of 162 feet, a depth of 16 feet, side slopes of 2 to 1 on the lower side and 1 to 1 on the upper side, a grade of .0000792, and a carrying of 10,640 second-feet. 2. From Siphon Drop to the sand hills the bottom width will be from 146 to 164 feet, a depth of 15 feet, side slopes from 1 to 1 to 2 to 1, a grade of .0000786 to .0000862 and an estimated carrying capacity of not less than 9,000 second-feet. The different widths, slopes, etc., are due to the different cross sections adopted to fit the varying character of the material to be excavated. 3. Through the sand hills the bottom width is 146 feet, a depth of 15 feet, side slopes 2 to 1 with a berme of 30 feet on either side at the surface of the mesa floor, which is the base of the sand dunes, a grade of .0000813 and a carrying capacity of 9,000 second-feet. 4. From the west side of the sand hills to Mesa Canal No. 1 the dimensions are the same as those used from Siphon Drop to sand hills. 5. Mesa Canal No. 1 to Mesa Canal No. 2 the bottom width is 125 feet, a depth of 12 feet, side slopes 1 to 1, a grade .00012 and a carrying capacity of 6,006 second-feet. 6. From Mesa Canal No. 2 to the East Side main canal a bottom width of 113 feet, a depth of 12 feet, side slopes 13 to 1, a grade of .00012 and a carrying capacity of 5.502 second-feet. 7. From the East Side main canal to near Allison Heading, a bottom width of 108 feet, depth of 105 feet, side slopes 1 to 1, a grade of .00014 and a carrying capacity of 4.546 second-feet. 8. From near Allison Heading to the Alamo River, a bottom width of 93.5 feet, depth 10 feet, side slopes 1 to 1, a grade of .000156 and a carrying capacity of 3,797 second-feet. 9. From the Alamo River to the Central main canal a bottom width of 82 feet, depth of 9.5 feet, side slopes 13 to 1, a grade of .00017 and a carrying capacity of 3,199 second-feet. 10. From the Central main canal to the West Side main canal, a bottom width of 46.5 feet, depth 8 feet, side slopes 13 to 1, a grade of .0002 and a carrying capacity of 1.495 second-feet. (d) No diminution has been made in the canal sections in this preliminary estimate, due to the loss of water, as we get farther away from the dam, as occasional storm waters must be cared for in the canal and it was thought |