The Arizona sentinel., 1903-11-04
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. Ii Is formed by the june l tion of the Green and Grand rivers, rising in l Colorado and Wyoming respectively, in re- 1 giOns Of great precipitation, mainly In the l form of snow. Only small percentage of the water yielded hy the basin of the Colorado | has as yet becn utilized for irrigation, and ! practically none for any other purposes. The obstacles are many. Through most of it's course this river and it's tributaries flow at | the bottom Of profound canyons, from hlch ' it k impossible To divert them upon irTgable 1 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 q series Of valleys which between thLs point i and the Mexican line aggregate about 500,CN0 1 acres. In this region the waters are heavily i laden with sediment, which Is a serious ob-
 stacle to their diversion The grade of the [ river is flat that a diversion canal taken
 out at the rivers bed must have so slight a
 a fall and SD low a velocity that it would
 quickly fill with sediment from the river. 1 For the same reason canal must be very
 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 1 that the river sometimes discharges a mini 1 mum of about 5000 cubic feet per second. It's
 maximum discharge is unknown, but proba- 1
 second. As the river is supplied mainly by
 melting snowS, It's season of high water cul-
 inmates 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 its
 mouth to the Needles by fiat-bottom, stern-
 wheel boats, which sometimes even ascend to 1 the mouth of Virgin river. It's navigation, | however, is so difficult and precarous as to
 make it almost useless. At low water the 1 channel is so broad. shallow and changeable 1 that boats are continually running aground, sometimes being nearly 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 thls basin are: First, the great fuctuatiOn in discharge; second, the paucity i Of land that can be reached by them; third,
 the large quantity of sediment. making inn
 practicable any diversion on small scale A 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, l in which this country is rich, is greatly ham, pered by the great cost of power and the lack l of transportation, both important requisites 1 for the mining industry. The proposed plan
 will completely solve both problems.
 | sUBrRoPICAL CLIMATE.
 All of the land that can be irrigated from ] the lower Colorado may he regarded as hav- ing a semi-tropical climate, where the grow l year rOund-the requirements for water, how ever, being greater in the summer season than 1 in the winter. It is here assumed that the maximum use in July will be twice as great as the minimum requirements in January; l and that a stream with the maximum flow of two cubic feet per second ill July, furnishing about 1000 acre-feet per annum, will supply 1 POO acres of land.
 l 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, all l lowing the great floods of wet years to sweep | to the sea as at present This will be Suffi- cient to irrigate 20O0 900 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 fen by alkali. All these it is proposed to re- claim by impoundng upon them the silt which annually passes down the Colorado river.
 SERIES OF DAMS.
 The general plan here proposed is the pro- vision of q series of reservoirs on the Colo TadO river by the construction of high da ms
 at numerous points where the topography is favorable and where the possible stOrago is
 
 with large siCcewayS through the base, in order that the stored waters may be entirely drawn off, togethrr with their load of silt, whenever 1t is found desirable to do The reservoirs will serve as settling basins for S"d- iment. The dams will also be utilized to
 raise 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 it can be deposited upon the fields. The declivity given tO the canals
 will depeDd largely upon the character Ofthe soil, and will be the highest permissible with out in volving destructive erosion. The fall of
 the Colorado river is so slight that reser-
 vOirS or enormous capacity may be construct ed without involving dams of practicable height. At any time, by opening the sluice ways of the reservoir, the current of tine river will quiciIly cut a channel through the de-
 posted sediment from the upper end of the
 reservoir to the Sluicp 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 eX- 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 be practicable, whenever desired, to close the SuiceS and inundate all of the agri- | cultural land in each filled reservoir and thus 1 fertiiZe it. as is naturally done by the river Nile for the valley. This is done artificially | in some parts of Europe and Africa. With | the deep, alluvial soil, semi-trOpical climate, l arid atmosphere, abundant water supply, | and the possibility of fertilizing the fields every year without expense, 1t is believed | that such regions can be farmed the year i round, and several crops taken off annually, an acreage production being thus attained | entirely without precedent in history.