CHAPTER XIV. 91 



mountains in heavy rains and note tiie waste winter water sinlting in 

 their boulders and gravels, you will see where the water does come 

 from. It Is only in extraordinary years that any of our torrents cross 

 the valley and flow to the sea. The exception to this rule is the water 

 delivery from denuded and burned off water-sheds. More of such rain- 

 fall storm-flow is lost. 



The moisture on the San Gabriel valley lands this year from the 

 rains in no case penetrated three feet. Eighteen inches is aoout the 

 average penetration. It is very rare that the rainfall moistens more 

 than ten feet down. The water level will average 150 feet in depth. 

 San Fernando wells shows the same condition. Those deriving their 

 water from these lower valley springs and dug or artesian wells derive 

 it in fact from the rainfall on the mountains just as surely as do those 

 whose pipe lines and ditches take the water directly in the mountains. 

 Their interest in the preservation of the mountain water-sheds is equal 

 to that of the mountain system owners. The damage from floods and 

 torrents is as great in the valleys as uear the mountains. The volume 

 of flood water is undoubtedly less th« (urther from the mountains you 

 go. 



This is one thing that makes the torrent more dangerous while it 

 lias any flow. It cannot carry its load of detritus as its volume de- 

 creases. This deposited in channels however, well defined in the start, 

 must and does raise them constantly. It becomes dilHcult, costly and 

 at last almost impossible to control torrents with water absorbing cones 

 like ours and increasing detritus delivery from burned and denuded 

 mountains. The worse the flres and forest destruction, the worse will 

 be the floods. Besides this, the more damage there is to the mountain 

 water-sheds, the more rapid will be the water delivery from them. 

 This lack of percolating time for the rainfall to get into the mountain 

 rock and soil will also result in a lack of percolating time to go 

 through the cone and washsieves into our subterranean lakes. 



Run one hundred millions of gallons of water from a mountain 

 water-shed to its cone of boulders, gravel and sand, and the time of 

 its delivery will govern what becomes of it. If this delivery is made 

 in one hour, you will have a flood, most of the waters in which will 

 pass by. If this delivery is over a period of ten days, no water will be 

 wasted at all. It is not necessary to go any further into an argument 

 or detail on this question in Southern California. We have seen the re- 

 sults of unwisdom in forest treatment. We know it from personal ob- 

 servation, and we fear for the future, unless our mountain waier-shedt 



