The Arizona sentinel., 1903-12-16
THE GREAT COLORADO RIVER

The great Colorado river is the largest stream, both in drainage area and discharge, that lies wholly within the arid portion of the United States. It is formed by the junc- tion Of the Green and Grand rivers rising in Colorado and Wyoming respectively, in re- gions of great precipitation, mainly In the form Of snow. Only small percentage of the water yielded by the basin of the Colorado has as yet been utilized for irrigation, and practically none for any other purposes. The obstacles are many. Through most of it's course this river and its tributaries flow at the bottom of profound canyons, from which it Is impossible to divert them upon irrigable lands. The river emerges from it's canyon a short distance above the Needles-the cross ing of the Santa Fe Pacific railroad-and has a series of valleys which between thus point and the Mexican line aggregate about 500OO0 acres. In this region the waters are heavily laden with sediment, which is a serious ob- Stacle 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 a a fall and so low a velocity that it would quickly fill with sediment from the river. long in order to command any considerable area Of land in the river valley.
 TWO AND QUARTER BILLION GALLONS A
 MINUTE
 Measurements of the flow near Yuma show that the river sometimes discharges mini mum of about 300e cubic feet per second. Its maximum discharge is unknown, but proba- bIy exceeds one-half million cubic feet per
 
 melting SnowS, its season of high water cul- minates in June, and the low water season is in the winter. when it's sources are frozen.
 The river is navigated more or less from it's mouth to the Needles by ffat-bottom, Stern- wheel boats, which sometimes even ascend to the mouth of Virgin river. Its navigation, however, is so difficult and precaTiOuS as to make 1t almost useless. At low water the channel is so broad. shallow and changcable that boats are continually running aground sometimes being nearly a week in advancing ten or fifteen miles. In times of high water the swift current greatly impairS 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 fiuctuation 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.
 comprehensive 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, pered by the great cost of power and the lack of transportation, both important requisites for the mining industry. The proposed plan will completely solve both problems.
 sUBTRoPICAL CLIMATE.
 All Of the land that can be irrigated from the lower Colorado may be regarded as hav- ing a semi-tropical climate, where the grow ing season for most products continues the year round-the req uirements 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 acrefeet 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 of water for industrial uses, varying from 10000 cubic feet per Second in winter to 10000 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 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.
 A 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 series of reservoirs on the Colo Tado 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 Ieservoirs will serve settling basins for sed- fn1ent The dams will also be utilized to raise the waters into canals, for the double purpose Of enclosing more iTrigable lands by such canals and of giving them a velocity sufficient tocaTry a large amount of sediment tn suspension until it can be deposited upon the fields. The decliYity 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 slight that reSer- VoirS of enormous capacity may be construct ed without involving dams of impracticabe height. At any time, by opening the Sluice- ways Of the reservoir, the current of the river will quickly cut 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 cases 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 it. 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 arable area. It will then he practicable, whenever desired, to close the sluiceS and inundate all of the agr- cultural land in each filled reservoir and thus fertiize it, aS is naturally done by the river Nile for the valley. This is done arliffcially in some parts Of Europe and Africa. With the deep, alluvial soil, semi-tropical climate arid atmosphere, abundant water supply, and the possibility of fertiliZing the fields every year without expense, it is believed that such regions can be farmed the year cound, and several crops taken off annually, rn acreage production being thus attained Rntirely without precedent in history.