The Arizona sentinel., 1904-06-15
THE GREAT COLORADO RIVER

THE GREAl GUlURAUU RlvtR
 The great Colorado river is the largest stream, both in drainage area and discharge. that lies wholly within the arid portion or fhe United States. It is formed by the juno tion ofthc Greer and Grand rivers rising m Colorado and Wyoming respectively, Tn re- gions of great precipitation, mainly In the Form of snow. Only a small percentage or 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 or it's course this river and its tributaries flow at the bottom of profound canyons, from which it Is impossible to divert them upon irTigable lands. The river emergeS from its canyon a short distance above the NecdleS-the cross ing of the Santa Fe Pacific ralroad-and has q series of valleys which between thIS point and the Mexican line aggregate about 5ntm acres. In this region the waters are heavily laden with sediment, which is a serious oD- stacle 10 their diversion The grade or the river is so fiat that diversion canal taken cut at the rivers bed must have so slight a :. fall and so low a velocity that it would quickly fill with sediment from the river. For the same reason a canal must be very long in order to command any considerable area of land in the river valley.
 TWO AND A QUARTER BILLION GALLONS
 MINUTE.
 Measurements of the flow near Yuma show that the river sometimes discharges a minl- mum of about 5000 cubic feet per second. It's
 
 bIv exceeds one-h.f million cubic feet per second As the river is supplied mainly by melting snows, its season of high water cul- Tnin;stes in June, and the low water season IS fin thp winter when it's sources arc frozen.
 The river is navigated more or less from its mouth 10 the, Needles by fiat-bottom, stern wheel boats, which sometimes even ascend to the mouth Of Virgin river. Its navigation; however is so difficult and precarlOuS as to make it almost useless. At low water the channel is so broad, shallow and changeable nhaf fc TO continually sometimes being nearly week in advancing ten or fifteen miles. In times of high water the swift current greatly inpairs navigation. Wherever wagon transportation lS possible, this is preferred to the river.
 The chief obstacle to the utilization of the waters of this basin are: First, the great Auctuation in discharge; second, the paucity of land that can be reached by them thlrd, the large quantity of sediment, making lln- practicable any diversion on a small scale
 X comprchensive project is here presented, which, if upon Investigation, is 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, of transportation, both important requisites for the mining industry. The proposed plan will completely solve both problems.
 sUBTRorTCAL CLIMATE.
 All Of the land that can be irrigated from the lower Colorado may be regarded as haN- a ing season for most products continues the year rOund-the req eQuirementS 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 a stream with the maximum flow of two cubic feet per second Ill July, TUT Iurnlshlng about 1000 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 a Sfp lnnnStrlal uses varying from 10000 cubic feet per second in winter to 20,0O0 cnbic feet per second in summer in years Of smallest discharge, al- lowing the great floods of wet years to sweep 10 the sea as at present. This will be Suffi- ricnt to irrigate 100000 acres of land, and is so far in excess of the requirements below the Grand Canyon that no restriction need to be put upon storage and diversion Of waters from the tributaries of the Colorado.
 X considerable portion of the valleys of the lower Colorado consists of sandy flood plains subject to occasional inundationS, and rough, gravelly 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 river.
 SERIES OF DAMS.
 The general plan here proposed is the pro- vision of a series of reservoirs on the COlo- Iado river by the construction of high dams at numerous points where the topography is favorable and where the possible storage is large. 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 found desirable to do so. The reservoirs will serve as settling basins for sed iment. The dams will also be utilized 10 False the waters into canals, for the double purpose of enclosing more irrigable lands by such canals and of giving them velocity sufficient to carry a large amount of sediment in suspension until il can be deposited upon the fields. The declivity given to the canals will depend largely upon the character of the soil, and will be the highest permissible with out involving destructive erosion. The fall of the Colorado river is SO slight that reser- voirs of enormous capacity may be construct ed without involving dams of inpracticable height. At anN time, by opening the Sluicc- ways of the reservoir, the current of the river will quickly cut a channel through the de posted sediment from the upper end Of the reservoir to the sluice gates; this being the longest dimension and deepest part Of the reservoir will in all eases form an important part of this storage capacity, and to this eN- tent every reservoir can be permanently kept clear Of sediment without expense. With this exception. each reservoir is expected to gradually fill; when this occurs ii is proposed to draw down the surface Of the reservoir permanently 20 to 10 feet, and to convert all of 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 arabic area. Ii will then be practicable, whenever desired, to close the sluices and inundate all of the agr- cultural land in each hlled resefYoIF ana mus frrtiliZe it, as is naturally done by the river Niic fnr the valley. This is done artificially jD some parts of Europe and Africa With the deep, alluVial soil, Semi-trOp1cal climate, arid atmosphere, abundant water supply, and the possibility of fertiiiZing the fields every year without expense. 1t Is believed hat such regions can be Harmed the year Found and several crops taken off annually, an acreage production being thus attained entirely without precedent in history.