252 



THE IRRIGATION AGE. 



filled with broken stone, and an apron of rock extends 

 40 feet beyond the lower wall. The structure between 

 walls is capped with a concrete pavement 18 inhes thick. 

 On the up-stream side of the weir a talus of broken rock, 

 with an incline of 2 feet horizontal to 1 foot vertical, 

 protects the concrete structure. The dam is 4,800 feet 

 long between abutments, 19 feet high in the river chan- 

 nel, and 226 feet in width up and down stream." 



The dam will raise the water about ten feet, back- 

 ing it up stream nearly ten miles and forming a set- 

 tling basin covering approximately 8 square miles. At 

 the west end of the weir, constructed in solid granite 

 rock and excavated to the depth of low water in the 

 .river, is a sluiceway 116 feet wide. At the east end the 

 sluiceway, also in granite, is only 40 feet wide. These 

 sluiceways are closed by large gates operated by hy- 

 draulic, machinery. These gates are of what is known 

 as the Stoney type, the only other gates of the kind in 

 the country being located in the Chicago drainage ca- 

 nal. They are of steel throughout, and are 18 feet high 

 and 35 feet wide. 



The diversion canals are taken from the sides of 

 the sluiceways above the gates. The areas of the sluice- 

 ways being so great the movement of the water toward 

 the canals will be slow, and most of the sediment will 

 be deposited before reaching the canal intakes. When 

 the silt has accumulated to a considerable depth the 

 sluicegates will be opened, and the great volume of 

 water which will rush through the sluiceway will carry 

 out with it the sediment deposited above the intakes of 

 the canals. As most of the silt is carried near the bot- 

 tom of the river and the top is comparatively free from 

 sediment, the water will be taken into the canals by a 

 skimming process, over a long row of gates, so the canals 

 can be filled by drawing but one foot in depth of water 

 from the surface. In times of flood the Colorado Eiver 

 overflows its banks, inundating the country for miles 

 around and in order to protect the lower lands an 

 elaborate system of levees has been built. These dikes 

 have an aggregate length of 75 miles, and are con- 

 sidered the most perfect ever constructed. The dimen- 

 sions of these embankments are those which experience 

 on the Mississippi River during the past 60 years has 

 proved to be the best. At base they are several times 

 as wide as their height. The tops of the dikes are four 

 feet above the highest known floods. The river side is 

 protected at frequent intervals by brush defences to 

 ward off the attacks of the river. 



A portion of the waters of the main canal on the 

 California side will be carried under the Colorado 

 River by a siphon, and used for the irrigation of land 

 near Yuma in Arizona. It is expected that consid- 

 erable power will be developed here which will be used 

 to pump water to the mesa lands. The farmers pump 

 and the big scoop wheel at Yuma are already furnish- 

 ing water to several thousand acres of bottom land be- 

 low Yuma. 



For months the great weir which the government 

 is building across the river had been creeping out from 

 either shore, the opening between the two ends gradually 

 narrowing until only 600 feet remained. Two tem- 

 porary railroad bridges, resting on piles driven deeply 

 into the yielding sands and silt on the bottom of the 

 river, were built above the dam, and from these rock 

 was dumped by the car load until on December 21st, the 

 river channel was completely closed and the water was 



backed up until it flowed through the sluiceways pre- 

 viously prepared. The work of connecting the ends of 

 the core walls was immediately commenced, and the 

 dam will be completed soon. 



Next October it is probable that 17,000 acres of 

 land in the Indian reservation on the California side 

 of the river will be thrown open to settlement. The 

 date and manner of disposing of these lands will be 

 announced by the Secretary of the Interior through the 

 public press. The other lands, for which water will be 

 available in 1909, are all in private ownership, but 

 there are many tracts of excess holdings or farms whose 

 owners do not reside in the vicinity that may be pur- 

 chased. 



In soil, climate, and agricultural possibilities the 

 lands of the Yuma project are singularly like those in 

 the valley of the Nile. Date palms and Egyptian cot- 

 ton have both proven well adapted to this section and 

 all the grains and fruits of the temperate and semi- 

 tropical zones produce abundantly. 



Alfalfa yields from 7 to 12 tons per acre and sells 

 at $6 to $10 loose in the stack. The baled hay brings 

 about $15. Yuma oranges, grape fruit, cantaloupes 

 and vegetables are the first on the market and their 

 quality is unsurpassed. On the experiment farm the 

 Department of Agriculture has set out more than 200 

 varieties of the date palm which were imported for the 

 purpose, and which will be transplanted to the rich 

 bottom lands as soon as water is available. The experi- 

 ments in cotton culture which the department has been 

 conducting on this little Government farm are most 

 interesting. It has been found that Egyptian cotton 

 of an excellent quality grows well in this section when 

 once acclimated, a test plat in 1907 yielding about 1,000 

 pounds of cotton lint per acre. The average price 

 during the year was 21.9 cents. We import about 

 62,000,000 *pounds of this cotton annually, and it is 

 estimated that 100,000 acres of such lands as is in- 

 cluded in the Yuma project easily would supply the 

 looms of our country. On the small farm units each 

 farmer could raise from three to five acres of cotton, 

 his own family harvesting the crop. This would sim- 

 plify the labor problem, give good returns, and allow a 

 considerable acreage for other crops. The Agricul- 

 tural Department has a limited supply of thoroughly 

 acclimated seed which may be used by such farmers 

 as are interested in this enterprise. Of interest in 

 this connection is the fact that cotton was grown quite 

 extensively in this region by the Pima and Maricopa 

 Indians before the discovery of America. 



The water supply is abundant and the lands, ex- 

 cept in very limited areas, are practically free from 

 alkali. The climate during the winter months is de- 

 lightful. The summers are hot, the' temperature some- 

 times reaching 120 in the shade. The sensible tem- 

 perature, however, is not much greater than in Wash- 

 ington where the percentage of humidity is so much 

 greater. Sunstroke is unknown. The nights are not 

 uncomfortable, and a large part of the population 

 sleeps out of doors the year around. 



Send $2.50 for The Irrigation Age, one year, and 

 the Primer of Irrigation, a 260-page finely illustrated 

 work for new beginners in irrigation. 



