The Arizona sentinel., 1904-07-06
THE GREAT COLORADO RIVER

HE 6hEA8 GNLuhkJu RfvEH
 The great Colorado river is the largest stream, both in drainage area and discharge that lies wholly within the arid portion o fhe United States. Ii is formed by the june lion of the Greer and Grand rivers, rising in Colorado and Wyoming respectively, in re gions of great precipitation, mainly In tue form of snow. Only a small percentage of the water yielded by the basin of the Colorado has as vet been utilized for irrigation, and practically none for any other purposes The obstacles are many. Through most of its course this river and it's tributaries flow al the bottom of profound canyons, from which tt Is impossible to divert them upon irrgablC lands. The river emerges from its canyon a short distance above the NeedleS-the cross ing of the Santa Fc Pacific railroad-and has g series of valleys which between thIS point and the Mexican line aggregate about 50n,0oO acres. In this region the waters are heavily laden with sediment, which is serious Ob- Rfacle to their diversion The grade of the river is so flat that a diversion canal taken out at the rivers bed must have so slight q fall and so low velocity that it would quickly fill with sediment from the river. For the same reason & canal must be very long in order to command any considerable area Of land in tine river valley.
 TWO AND A QUARTER BGLLIo:i GALLONS A
 MINUTE.
 Measurements of the flow near Yuma show that the river sometimes discharges a mini mum of about SG00 cubic feet per second. Its
  ply exceeds one-half million cubic feet per second. As the river Is supplied mainly by ynelting snOws, it's season of high water cul- s1inates in June, and the low water season is ta the " inter. when its sources are frozen.
 The river iS 6av Iga tad IDoEc Or less from it's mouth To the Needles by fat-bottom, stern- wbeel boats, which sometimes even ascend tO fine mouth Of Virgin Ttver. Its navigation, however, is so difficult and precarious as to make It almost useless. At low water the channel Is SO broad. shallow and changeablc af Tnnn1nC aground. sometimes being nearly week in advancing ten or fifteen miles. In times of high water the swift current greatly irnpairS navigation. Wherever wagon transportation is possible, this is preferred to the river.
 The chief obstacle to the utilization Of the waterS of this basin are: First, the great fuctuation in discharge; second, the paucity of land that can be reached by them; third, the large quantity of sediment making inn practicable any diversion on small scale.
 X comprehensive project is here presented, which, if upon investigation, jS found inn practicable, will largely remove all of these difficulties, and will also greatly improve navigation at all seasons of the year.
 The development Of the mineral resources in which this country is rich, is greatly ham, pcred by the great cost of poweran the lack of transportation, both important requisites for the mining industry. The proposed plan will completely solve both problems.
 sUBTRorTeAL CLIMATE.
 All of the land that can be irrigated from the tower Colorado may be regarded as hav- .ag a semi-tropical climate, where the grow ing season for most products continues the year round-thc requirements for water, how ever, being greater in the summer season than in the winter. It is here assumed that the maximum use in July will be twice as great as the minimum requirements in January; and that stream with the maximum flow Of two cubic feet per second in July, furnishing about lOOO acre-feet per annum, will supply 200 acres Of land.
 It is probable that with proper regulation the Colorado river will be able to furnish continuous stream ot water for industrial nses varying from l0,000 cubic feet per second in winter 10 20000 cubic feet per second in summer, in years of smallest discharge, al- lowing the great floods of wet years to sweep to the sea as at present. This will be Suffi- cient to irrgate 2.000,000 acres of land, and is so far in excess Of the requirements below the Grand Canyon that no restriction need to be nut upon storage and diversion of waters from the tributaries of the Colorado.
 A considerable portion Of the valleys of the lower Colorado consists of sandy flood plains subject to occasional nundationS, and rough, eravely foothills with soil unsuitable for cul- tivation. There are also considerable areas of sand dunes, and some tracts rendered bar ren by alkali All these it is proposed to re- claim by impounding upon them the silt which annually passes down the Colorado Eyer.
 SERIES or DAMS. The general plan here proposed is the pro- vision Of series Of reservoirs on the Colo rado river by the construction of high dams | st numerous points where the topography is | favorable and where the possible storage is l barge All of these dams will be provided | with large Sluiceways through the base, in order that the stored waters may be entirely drawn of, together with their load Of silt, whenever it is fouDd desirable to do so. TlTe ycservOirs will serve as settling basins for seG- ineut. The dams will also be utilized t0 yaisc the waters into canals, for the double | purpose of enclosing more irrigabhe lands by such canals and of giving them a velocity sufficient to carry a large amount of sediment tn suspension until it can be deposited upon the fields. Fhe deeiivity given to the canals will depend largely upon the character Ofthe soil, and will be the highest permissible with out involving destructive erosion. The fall Of the Colorado river is so sight that reser- roirS Of enormous capacity may be construct ed without involving dams of impracticablc height. At any time, by opening the siuice- ways of .ife reservoir, the current of the river will quickly cut a channel through the de- posted sediment from the upper end of the to the sluice gates; this being the longest dimension and deepest part Of the will in all cases form an important part or this storage capacity, and to this ex- tent cverr reservoir can be permanently kept slear Of sediment without expense. With fhiS exception each reservoir is expected to fill; when this occurs ii is proposed to draw down the surface of the reservoir 20 to 10 feet, and to convert all sf the reservoir site except the river channel into irrigated farming land, and, if necessary. construct another reservoir for storage pur- poses higher up on the stream. This policy will greatly increase the arabe area. It will then be practicable, whenever desired, to rlose the sluices and inundate all Of the agri- cultural land in each filled reservoir and thus 'ertilize it, as is naturally done by tho river Nile for the valley. This is done artifcially n some parts of Europe and Africa. With he deep alfuyial soil, semi-tropical climate, Erid atmosphere, abundant water supply, and the possibility of fertiiiZing the fields every year without expense. it is believed hat such regions be farnled the year sound, and several crops taken off annually. ; zn acreage production being thus attained history