BANCROFT LIBRARY LETTER FROM CHIEF ENGINEER OF THE U. S. GEOLOGICAL SURVEY RELATIVE TO THE IRRIGATION OF LANDS IN THE VICINITY OF YUMA UNDER THE PROVISIONS OF THE RECLAMA- TION ACT OF JUNE 17, 1902. Bancroft Library YUMA COUNTY WATER USERS' ASSOCIATION. YUMA, ARIZONA, May 3, 1904. To THE HONORABLE E. A. HITCHCOCK, SECRETARY OF THE INTERIOR, WASHINGTON, D. C. As the work of investigating the conditions along the lower Colorado River and preparing plans for irrigation works has been completed by the members of the United States Geological Survey detailed for that purpose, and as their work has been examined by the final Board of Consulting Engineers, and, as we understand, a favorable report made to your Department, therefore, it is deemed proper by the Board of Governors of the Yuma County Water Users' Association, a body legally organized under the laws of the Territory of Arizona for the purpose of securing the irrigation of lands in the valley of the Colorado River in Yuma County, Arizona, by the Government, under the law commonly known as the Reclamation Act, to take the following action : 1. To submit to you a certified copy of the Articles of Incorporation of the Yuma County Water Users' Association for your inspection. 2. To furnish you with the names and credentials of the President, Secretary and Board of Governors of the Association. 3. To convey to you the earnest desire and request of this Association, by its Board of Governors, for the construction of irrigation works on the lower Colorado River, and to pray you to furnish to the people of this section, through this Associa- tion, a statement of the character and cost of the said proposed irrigation works, with instructions as to how we shall proceed in order to do our part in securing the construction of the same. 4. To assure you, by a petition numerously signed, and by other means, of the almost unanimous desire of the people here for the construction of irrigation works as planned. Therefore, in accordance with the foregoing action of the Board of Governors, I have the honor to transmit herewith a certified copy of the Articles of Incorporation of the Yuma County Water Users' Association ; the attested credentials of its officers ; a petition signed by the members of the Board of Governors, praying for the con- struction of irrigation works on the lower Colorado by the Government, and for in- formation and instruction for the guidance of said Board ; a petition of like nature, signed by a large number of the leading farmers and land owners of this section ; a resolution passed by the City Council of the town of Yuma, and one by the Yuma Board of Trade, which is composed of over 200 members, many of them farmers. All of which is most respectfully submitted. [Signed] M. WINSOR, f "^ President. DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY HYDROGRAPHIC BRANCH WASHINGTON, D. C., MAY 16, 1904. YUMA COUNTY WATER USERS' ASSOCIATION, M. WINSOR, PRESIDENT, YUMA, ARIZONA. Gentlemen : Your communication of May 3d, 1904, accompanied by petition under same date, and also certification of officers of the Yuma County Water Users' Association, is hereby acknowledged. The Chief Engineer of the United States Geological Survey will meet your officials at Yuma, May 27th next, to confer with them concerning such matters as you may present relative to your organization. In reply to your request for information as to cost and character of works pro- jected for your locality, the following general statement is presented. The Secretary reserves the right to make such revisions in the plans and estimates as further investigations and circumstances may dictate to be requisite for the public welfare. During the winter season of 1903-4 the Reclamation Service made surveys for the irrigation of the vallev lands of Colorado and Gila Rivers in the immediate vicinity of Yuma, Arizona, and in the Yuma Indian Reservation in California, looking towards the utilization of the Colorado River for their water supply. These surveys included the making of a topographic map, on the scale of 100 feet to the inch, at the Laguna Dam Site, and soundings for bedrock and foundations at that point. On the California side of the river, along the route to be occupied by a possible canal, a map has been made on the scale of 100 feet to the inch, with a small contour interval. On the Arizona side of the river a map has been made, on the scale of 100 feet to the inch, from the Laguna Dam Site to Yuma along the canal line, and in addition a number of angle line surveys have been run for the exact determination of the location for the canal. Below Yuma, transit surveys have been made for the location of the canal. At the crossing of the Gila River a map has been drawn on a scale of 100 feet to the inch, and soundings made for bedrock. Preliminary location surveys have been made for a complete set of levees from the Laguna Dam Site to the Mexican line, on both sides of the Colorado River, and also on each side of the Gila River. A drainage system has been projected upon the topographic maps which have been made of the entire district to an elevation of 150 feet above river level, and to the scale of 2 inches to the mile. Surveys have been made to base estimates upon for pumping plants for irrigation and drainage. Mr. H. A. Storrs, Consulting Electrical and Mechanical Engineer, has examined the ground and made plans and estimates therefor. A Board of six Consulting Engineers has been through the estimates of the Engineers in charge in detail, and the report which is submitted is the result of the deliberations and best judgment of all these men, and all estimates and plans have been brought to the complete satisfaction of each person. AREAS. In the Yuma Indian Reservation on the California side of the river it is estimated that there will be within the levees 16,000 acres, and on the Arizona side it is estimated there will be 91,000 acres under the system, making a total of 107,000 acres. Of this area, it is estimated that 5,000 acres next to the Mexican line in Arizona will be sub- ject to overflow in such a way as to temporarily exclude them from the irrigable areas, and in addition a small percentage of the remaining lands are known to be in sand dunes that will be above the level of the canal lines. In all it is estimated that on both sides of the river there will be a total of 86,700 acres of irrigable land, of which 73,100 acres are in Arizona. The water supply of the Colorado River is adequate for the irrigation of this area. HEAD WORKS. A number of different designs for the diversion weir have been estimated upon in the study for the most economical type that may be built in safety at this point. Several different locations have also been examined to determine the best place for this structure, bedrock having been explored for with diamond core drilling machinery at all possible dam sites between Yuma and Picacho. As a result of these explorations the Laguna weir site has been selected as the most desirable one for the construction of a weir to serve the lands near Yuma, a high dam and high line canal being consid- ered impossible. The type of weir selected is one that has been tried during the last 50 years at numerous places in India and Egypt under similar conditions, 3 dams having been constructed on the Nile River within the past 15 years, on practically this same plan, all having served their purpose efficiently and being in operation today. This type of weir consists of a loose rock structure with a paving of stones 1% feet in thickness on the down-stream slope, the structure being tied together with three parallel walls of steel and concrete run longitudinally between the granite abutments on the two sides of the river, and the entire structure being further made secure by an apron of loose rock pitching 10' in thickness and 50' in width at the lower toe of the dam below the sloping pavement. The height of this weir is to be 10' above low water and the slope of the downstream side is 12' horizontal to 1' vertical, with the 50' apron below. The design calls for the upper core wall of concrete to rest upon a row of sheet piling driven into the bed of the river. The handling of the silt of the Colorado is one of the most difficult features of this undertaking. It is known that its amount is very large. The river is on a grade of approximately one foot to the mile above the Laguna weir site, so that this weir 10' high will make a settling basin of relatively quiet water approximately 10 miles in length above it. At each end of the weir and constructed in solid granite rock, will be a sluice way 200 feet wide and excavated to the depth of low water in the river. These sluice ways will be closed by large gates opera ted by hydraulic machinerv. The diversion canals will take their water above these gates from the sides of the sluice ways. The area of these sluice ways being so great, the water movement toward the canal will be slow, and most of the sediment will be deposited before reaching the canal intake. When this has accumulated to a considerable.extent, the sluice gates will be opened, and it is estimated that their capacity will be approximately 20,000 cubic feet per second each. This great volume of water passing through the sluice ways, when the gates are opened, will carry out with it the sediment deposited above the intake of the canal. The ordinary low stage flow of the Colorado River is from 3,500 to 4,000 cubic feet per second, so the capacity of each of these sluice wa3 r s will be about five times the low water flow of the river. These figures are given for pur- poses of comparison only. As the result of a number of experiments, it has been found that the principal quantity of silt is carried along near the bottom of the river, and that the surface water is relatively free from sediment. It is planned, therefore, to take the water into the canals by a skimming process over a long row of flashboards, so that the entire capacity of the canal can be furnished by drawing but one foot in depth of water from the surface of the river. As a still further precaution, it is proposed to construct the first 3,000 feet of canal on each side of the river of such size that the movement of water through it will be slower than one foot per second. Thesesettling basins, as the3 r are called, would be either excavated from granite, or where the sec- tion is in earth they would be paved. At the lower end of these settling basins, gates will be arranged to discharge into the river, so that the water can be drawn down to the level of the stream, and a grade of 11 feet in 3,000 feet thus obtained. At the lower end of these settling basins the canals proper will begin. The silt that will enter the settling basins in spite of the two precautions noted above, will be permitted to settle in these basins, and at such intervals of time as may be necessary the sluice gates at the end of the settling basin will be opened and sufficient water drawn into this section through the headworks to scour it out. Every portion of this weir and headworks as designed would be of rock, concrete or steel, with the ex- ception of the sheet piling, which will be driven entirely below the water level, and so will not decay. Every portion of the weir will be what is known as permanent con- struction. Such character of work will, of course, be expensive, but it has been proved to be sound economy to build in this way. The capacity of these canals at their intakes will be 1,200 cubic feet per second on the Arizona side, and 200 cubic feet per second on the California side. The amount of silt that would be daily delivered into the Arizona canal, if diversions were not made directlv from the stream, would approximate 17,000 cubic yards of wet mud by volume. It is not believed to be possible for a canal to continuously operate suc- cessfully for the irrigation of lands along the valleys of the Colorado River, unless some very substantial arrangements are made at the headworks for the handling of silt, and this is believed to be a justification for the expenditure proposed for these headworks; also the water must be held to a fixed level at the canal heading for all stages of the river. This structure will cost approximately $1,000,000. CANALS. Careful study has been made of the existing canals in the vicinity of Yuma and Imperial to determine the shape that they naturally assume, and the roughness of the bottom and sides, which tends to retard the velocity. Based upon this data, the canals have been designed so they will carry water at a higher velocity through- out than will be found in the settling basins above their head, and of such velocity as will permit of a minimum loss by seepage and evaporation. The gates and drops of these canals, and the Yuma bridges are designed as steel concrete structures. A dis- tribution system has been estimated upon to furnish water to each 160-acre tract. There will be small areas of land in the upper Gila Yalle3', and below Yuma that will have to be served by pumping plants that will lift the water from 5 to 7 feet. The power for doing this will be furnished from a water power plant to be erected above Yuma at a drop in the main canal. This power plant will also be used in connection with the drainage system. GILA CROSSING. One of the most difficult problems in connection with this project is the crossing of the Gila River. It has been considered necessary to make this perfectly safe, and for this purpose a structure has been designed that will cross beneath the bed of the river, the top to be several feet below the lowest point of the stream bed. This structure will be of steel and concrete, some 3,300 feet in length. LEVEES. Because of the annual rise of the Colorado River, a large portion of the lands along this stream are subject to annual overflow which practically prevents residence there- on, as well as the farming of them without protective works. The levee, therefore, is considered an essential feature of the enterprise. The shape of levee adopted is one that has been developed by years of experience along the Mississippi River. It will have a slope of 3 feet horizontal for 1 foot vertical on the water side, and 2V& feet hor- izontal to 1 foot vertical on the land side; it will be 8 feet wide on top, and be built 5 feet above the highest water-marks of the year 1903. These levees will be 4,000 feet apart (one on each side) along the Colorado River, and 3,200 feet apart along the Gila River. DRAINAGE SYSTEMS. Because these lands are so flat, and the level of the water in the ground so near the surface, it is considered necessary, for their permanent safe irrigation, to supply a drainage system. A main drainage canal has been designed to run through thecentral portion of the areas to be irrigated, and when possible the natural drainage lines of the country will be utilized, deepening them with a steam dredger to such depth that they will carrv off the water returning from irrigation or seeping through the levees during the high-water stage of the river. When lands in any district tend to become alkaline they may be connected, by means of local drainage canals, with this main drain, and in this manner they could be kept free from alkali by holding down the level of the ground water. During the greater portion of the year when the river is low, this drainage water would be dis- charged into the stream, but when the river is in flood its elevation will be such as to prevent a discharge into it from the drains. A pumping plant has therefore been de- signed to lift the drainage waters over the levees during the flood period of the river to prevent the lands becoming water-logged. SUMMARY. The whole system, as planned above, is one looking to the permanent reclamation of this district by means of irrigation, levee and drainage works. All portions of the system to be made of steel, concrete or earthwork. The reports of the Department of Agriculture on the character of the soils of this valley, as well as past farming experience, indicate that they are exceedingly fertile. The silt of the Colorado River, all of which cannot be removed at the headworks, has high fertilizing properties. Under these conditions and with proper handling of the system, the valley should be perpetually fertile. The entire cost of this enterprise, pro- viding all the area is irrigated which is indicated above, will amount, according to the estimate, to about $35.00 per acre irrigated. It is entirely possible, however, that as this construction work proceeds this cost may be somewhat increased or lessened, al- though an effort has been made to cover all contingencies, and the estimates of cost have been liberal. The price will range near $35.00 per acre, this to be paid for accord- ing to the provisions of the Reclamation Act and regulations of the Secretary of the Interior, in ten annual installments after the first delivery of water. The annual charge for maintenance and supervision of this system will be very low and probabh' materially less than $1.00 per acre. There will be no charge for interest, profit or taxes. In order to keep the price as low as that estimated upon and to proceed with the construction of the works, it will be necessary for all of the land owners of the portion of the district that is in Arizona, under the projected canal, to enter into an agreement with the Secretary of the Interior through their local Water Users' Association for the payment of the water when it is delivered to them. The Reclamation Service has made the surveys and estimates required for the Secretary of the Interior concerning the costs and character of these works, but it will be absolutely necessary for the local land owners to submit to the Secretary, through their local associations, the contracts for the acceptance of the water; and also to provide for the rights of way required for the levee, power plants, transmission lines, etc. When these contracts and agree- ments have been prepared they will be given careful consideration by the Department. The Secretary of the Interior has set aside $3,000,000 of the Reclamation fund for the construction of this project, contingent upon the action of the land owners of this valley and their entering into contracts with the Department in accordance with the provision of the Reclamation Act passed June 17, 1902, as indicated by the following letter : THE DIRECTOR OF THE MAY 10, 1904. GEOLOGICAL SURVEY. Sir: In a letter of the 9th inst. to the Department you referred to the Act of April 21, 1904, Public, No. 125 which has authorized the Secretary of the Interior "to divert the waters of the Colorado River and to reclaim, utilize and dispose of any lands in said reservations, " etc., and have referred to the surveys which have already been carried on under the Act of June 17,1902 32Stat.388 and to the reports submitted by the engineers. It appears that under the Yuma project and by means of a dam across the Colo- rado River and other works, upwards of 85,000 acres of land can be reclaimed at a cost of less than $40 per acre. You have stated that much of this land, outside of the Indian Reservation, is in private ownership, and that the feasibility of the project will depend largely on the owners of the land uniting in a satisfactory form of organization under the terms and conditions of the reclamation law. Your recommendation is that the sum of $3,000,000 be set aside from the recla- mation fund for the construction of the Yuma project, subject to the satisfactory ad- justment of the various matters pertaining to land and water titles and to structural features. Incompliance with your recommendation, I hereby set aside the sum of $3,000,000, or so much thereof as may be necessary, from the fund provided by the Act mentioned, for the construction of the Yuma project, under the conditions you have set forth. Yours respectfully, [Signed] E. A. HITCHCOCK, Secretary. F. H. NEWELL, Chief Engineer. U.S. RECLAMATION SERVICE. LOWER COLORADO RIVER. MAP SHOWING LOCATION OF IRRIGABLE LANDS, PROPOSED DAMS, CANALS, LEVEES a PUMPING PLANTS. Library k o i >o- - if..-' - ;i.fT> | >- i i