1905 



FORESTRY AND IRRIGATION 



369 



fall, are among- the factors which 

 must be taken into account. 



Some of the conditions disclosed by 

 these investigations bring out clearly 

 how far agriculture has advanced 

 from the time when men threshed 

 grain with a frail and depended for 

 travel on the slow-moving horse and 

 cart. The irrigators of California 

 have to be more than irrigators. They 

 are dealing with questions that in- 

 volve an expert knowledge of me- 

 chanics, of electricity, and of social 

 and economic relations wholly outside 

 the practical interests of the cultivator 

 who farms where the rainfall is am- 

 ple. Men's capacity is determined by 

 what they attempt and achieve and 

 it is not at all surprising that the irri- 

 gation communities that are having 

 to deal with these broad problems 

 show a general intelligence and civic 

 capacity far above the average. 



One example will be given of the 

 kind of mechanical problems irriga- 

 tion requires the farmers to solve. 

 Eight miles north of Ontario is an 

 electric power station, chiefly used to 

 pump water for irrigation. The power 

 is brought to the colony by transmis- 

 sion lines under 10,000 volts pressure. 

 It pumps water from wells in the de- 

 bris at the foot of the San Gabriel 

 Mountains. This debris catches the 

 water which comes down from the 

 mountains and holds it practically in 

 a covered reservoir. There are eight 

 wells reaching down into this under- 

 ground storage basin. A description 

 of one will apply to all. The power 

 which lifts water from this well is car- 

 ried under a 2,2OO-volt pressure which 

 runs a 50 horse-power horizontal in- 

 duction motor capable of working con- 

 tinuously at a 60 horse-power output. 

 It runs a vertical centrifugal pump 

 placed at the bottom of a timbered 

 shaft 140 feet deep, which is fed from 

 a 12-inch tube well sunk 460 feet. 



The farmers who depend on these 

 and other wells not only have the set- 

 tlement of the types and kinds of 

 power which they shall select and 

 which they can afford to employ, but 



they have to consider their relation to 

 the ownership and stability of this un- 

 derground water supply. The exten- 

 sion of pumping has caused a pro- 

 gressive lowering of the water plane 

 of this region. In some localities the 

 water level has fallen steadily at the 

 rate of 10 feet per year. The water 

 which fills the Gage Canal at River- 

 side was originally furnished almost 

 entirely by flowing artesian wells. 

 Gravity filled the canal. Now the low- 

 ering of the water plane requires 30 

 cubic feet per second to be pumped 

 and has raised the cost of irrigation 

 per acre from $2 to $7.66. 



The progressive lowering of the 

 water plane, partly due, no doubt, to 

 a succession of dry seasons, has made 

 the question of rights to underground 

 waters almost as important as rights 

 to surface water and has brought up a 

 new class of legal and economic ques- 

 tions connected with water rights. One 

 of the duties of this office, as defined 

 by Congress, is to investigate and re- 

 port upon the laws affecting irrigation 

 and upon institutions relating to irri- 

 gation. California is one of the most 

 interesting and fruitful fields for these 

 studies. At present, however, the 

 chief purpose of the work is to devise 

 improvements to lessen losses from 

 seepage and evaporation so as to post- 

 pone controversies over rights. This 

 can be best done by lessening the 

 quantity of water required for each 

 acre irrigated, and this is the problem 

 to which the office is addressing itself 

 particularly during the present season. 



Irrigation and drainage are two 

 parts of a single problem. Drainage 

 always has to supplement irrigation 

 where seepage water or excess of al- 

 kali makes an accumulation of soil wa- 

 ter a menace to continued productive- 

 ness. Measurements of the rise of 

 soil water, measurements of seepage 

 losses, and surveys of areas requiring 

 drainage, are being carried on in va 

 rious parts of California where the 

 reclamation of swamped and alkalied 

 lands is now, or will in the future be, 

 an important productive factor. 



