112 



THE IRRIGATION AGE. 



sin, if absolutely instead of only approximately correct, 

 is positively misleading. At the point of outflow, .if the 

 runoff is only one-tenth of the rainfall of the basin, it 

 is of course impossible to use more than one-tenth 

 at or below that point. But that is not in the basin at 

 all. The question is: How much water is recover- 

 able and usable in the basin? At least that is the 

 question over large areas of the plains. In consid- 

 ering this problem the division of the immediate dis- 

 position of the rainfall into three parts, as given in a 

 previous paragraph, must be understood, and the 

 amount of seepage as before defined becomes of im- 

 portance. 



SEEPAGE. 



It is quite possible, and in many districts highly 

 probable, that the seepage may amount to fully one 

 half of the rainfall and yet the final runoff be not 

 more than a tenth. In the semi-arid regions, the line 

 of saturation of the rocks is some distance below the 

 surface, in some cases over a hundred feet. It fol- 

 lows then that for at least the greater part of the year 

 the surface formations are relatively at least very dry. 

 They are then capable of rapid absorption of water. 

 True, the buffalo-grass sod of wide areas of the prai- 

 ries is almost like a shingle roof in a rainstorm and 

 the immediate runoff is great, but there are areas 

 where the sod is of different nature or missing alto- 

 gether, and the surface is highly absorptive. This 

 and the dryness of the subsoil combined make it cer- 

 tain that a large proportion of the seepage goes into 

 depths where it is conserved for some time before be- 

 ing brought to the surface in feeble or strong springs 

 to be again diminished by evaporation. It is impor- 

 tant to remember that the drier the atmosphere the 

 more rapid the evaporation. It is just as true that 

 the drier the subsoil the greater the seepage. 



It is conceded it is a matter of repeated observa- 

 tion that the plowing of the soil, the breaking of the 

 prairie sod on the plains has increased the moisture 

 in the subsoil; that is, the seepage is greater. Yet the 

 totality of runoff is probably only temporarily inter- 

 fered with. 



The relatively large seepage in and through dry, 

 porous soils and subsoils in the semi-arid region is a 

 factor to be considered in dealing with the estimate 

 of recoverable water in the shallow basins of the com- 

 paratively level regions west of the 100th meridian. 

 The estimate of Prof. Van Diest that for eastern 

 Colorado, probably five inches of rainfall are recov- 

 erable from underground, is in my opinion approxi- 

 mately correct, and it will apply to adjoining parts of 

 Nebraska, Kansas and Texas. 



I do not know of any series of measurements of run- 

 off on the great plains. But applying the least favor- 

 able estimates as in No. ,ante, with the consideration 

 of seepage suggested above, it is certain that given 



the mechanical means for raising water, large regions 

 of the plains may be redeemed by irrigation. That 

 is, apart from what may be done on slopes and in val- 

 leys the farms on level prairie may have, each of 

 them through extensive regions, enough water to irri- 

 gate five, ten or fifteen acres out of the quarter sec- 

 tion. On five acres, irrigated, the farmer can live 

 well; on the larger areas, he can accumulate savings 

 year after year, and on the rest of his land he can 

 grow grass or wheat as the seasons allow at present. 



There are now hundreds of wells on the high prai- 

 ries that by all strain yet put on them are inexhaus- 

 tible. Let them be tested to the limits of irrigable 

 possibilities on their owner's farms, and the store of 

 water underground will, in the writer's belief, be kept 

 up from the rainfall through the medium of seepage 

 on the increasing area of the more absorptive because 

 more highly cultivated land. 



IN SOUTHERN CALIFORNIA. 



From latest reports in Southern California, some of 

 the oranges have been frozen again this year, the ex- 

 tent of the damage not yet being definitely known. 

 THE AGE has stated before that there are many 

 places in the supposed orange belt that do not prop- 

 erly belong to the real orange belt, and even some 

 portions of each of the choice orange colonies could 

 be more profitably devoted to the raising of deciduous 

 fruits. When all the lands in California that are 

 frostless shall have been supplied with a good water 

 right, and are set to orange trees which have grown 

 to their full bearing capacity, there will not be more 

 than enough to supply the demand at good prices; 

 but those who engage in this business should be sure 

 that they have the proper location, that the climate 

 as well as the soil and water is well adapted to the 

 production of choice oranges, otherwise other fruits 

 will prove more profitable. 



ARROW HEAD RESERVOIR. 



A representative of THE AGE visited Cincinnati 

 recently, and while there called at the office of the 

 secretary of the Arrow Head Reservoir Company, 

 who stated that work would commence in early spring 

 on the construction of their works there, and would be 

 pushed through until completed. This is one of the 

 most extensive works of the kind producted, and will 

 prove a profitable investment to its builders, as below 

 this system will be found an immense area of the 

 most valuable land in California that is not supplied 

 with water, and this is about the only system that 

 will be able to supply them. If constructed on an 

 economical and capable basis the construction of this 

 reservoir will prove a blessing to both the water users 

 and the water sellers. 



