The Arizona sentinel., 1903-05-27

A COmpfeueuSlEo pIOJ0CU To here presented which, ifupon in vestigation is found practicable, will largely remove all of these difficulties, and will also greatly improve navigation at all sea sons of the year.
 The development of the min eral 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.
 All of the land that can be ir- rigated from the lower Colorado may be regarded as having d semi-tropical climate, where the growing season for most prod uctS continues the year round the requirements for water, how ever, being greater in the sum- mer season than in the winter. It is here assumed that the max imum use in July will be twice as great as the minimum re- quirements in January; and that a stream with a maximum flow of 2cubic feet per second in July, furnishing about 1000 acre-feet per annum, will supply 200acres of land.
 It is probable that with proper regulation the Colorado river will be able to furnish a cOntinu- ous stream of water for indus trial uses, varying from 10000 cubic feet per second in winter to 10000 cubic feet per second in summer, in years of smallest discharge, allowing the great floods of wet years to sweep on to the sea as at present. This will be sufficient to irrigate ,, 100000 acres of land, and is sc far in excess of the requirements below the Grand Canyon that nc restriction need to be put upon storage and diversion of water from the tributaries of the Colo rado.
 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 cultiva tion. There are also cOnsidera ble areas of sand dunes, anC some tracts rendered barren by alkali. All these it is proposed to reclaim by impounding upor them the silt which annually passes down the Colorado river
 A SERIES OF DAMS.
 The general plan here pro posed is the provision for a SC ries of reservoirs on the Cobra do river by the construction O high dams at numerous points where the topography is favora ble and the possible storage i large. All of these dams will b. provided with large sluiceway' through the base m order tha the stored waters may be entire ly drawn off, together with thei
 load of silt, whenever it is fount desirable to do so. The reSer
 voirs will serve as settling ba sins for sediment. The dam will also be utilized to raise tn waters into canals for the dOubl
 purpose of enclosing more irri , gable lands by such canals an'
 of giving them velocity sufficien : to carry a large amount of sedi ment in suspension until it ca E be deposited upon the fields The declivity gwen to the canal will depend largely upon tn , character of the soil, and will b the highest permissible withOu : involving destructive erosion 5 The fall of the Colorado river l , so slight that reservoirs of enOl : nous capacity may be construct 5 ed without involving dams c
 impracticable height. At an 3 time by opening the sluiceway 3 of the reservoir the current C : the river will quickly cut char 5 nel through the deposited sed ment from the upper end of tn