THE DRAINING DISTANCE OF 

 UNDERGROUND WATER. 



A PRACTICAL DEMONSTRATION OF THE EFFECTS 

 OF UNDERFLOW DEVELOPMENT. 



BY T. S. VAN DYKE. 



r~nHE reliable nature of most of the un- 

 JL dergrouud water supply of Southern 

 California has been well proved by a recent 

 series of three years of short rainfall in 

 which two were a little below half the 

 average and the other one just about the 

 average, with bad distribution. This was 

 a very severe test, but every draining work 

 that was in any kind of proper ground 

 stood it with scarcely a sign of diminution. 

 Much of the water supply of the future 

 elsewhere, as well as in California, will be 

 of the same nature, though there is noth- 

 ing about which it is so easy to be deceived 

 as the amount of water that may be had in 

 this way. 



The common impression is that a drain- 

 ing flume or tunnel draws from a level all 

 around it, the level being gradually low- 

 ered from its natural elevation down to a 

 certain point at which it continues to 

 stand. An expert who would think a few 

 minutes would say that such would not be 

 the case if the water were in motion at 

 all, or had a regular supply, and that if it 

 did not have such a supply it must in time 

 drain out and could not reach any level at 

 which it would stand continuously. But 

 very little in the line of demonstration of 

 this principle has ever been done, and it is 

 a very important one for all -interested in 

 water development to understand. In a 

 recent case in the Superior Court of Los 

 Angeles in which 1 was engaged to study 

 up the case as an expert witness, we had 

 the only complete proof of it that I have 

 been able to find in the Southwest. 



A PRACTICAL DEMONSTRATION. 



In December, 1895, the West Los An- 

 geles Water Company made a cut some two 

 thousand feet long and eighteen feet deep 

 at the upper end. A flume was laid in 

 the bottom from which nearly five hun- 

 dred inches of water have been flowing ever 

 since and almost unaffected by the series 

 of short years. During the two months 

 the cut was making, and the water in- 

 creasing every day, several wells on places 

 from a thousand to two thousand feet up 

 stream showed a gradual fall of their 

 water level, which amounted in the two 

 months to four feet. In June, 1896, an 

 extension was made which took six weeks 

 and resulted in developing more water at 

 about the same rate as that in the main 

 flume. During this six weeks the water 

 in the well sank sixteen inches. 



The fall of water in the wells was 

 marked by nails driven in the curbing 

 every week during each of the periods and 

 was sworn to by a number of witnesses. I 

 and the other witnesses for the Company 

 examined them with care and concluded 

 the_y were genuine, and there is no reason 

 to believe that we were mistaken. On the 

 trial of Yarwood et al. vs. the West Los 

 Angeles Water Co. these facts stood un- 

 contradicted. 



Here was a prima facie case that would 

 make many a lawyer smile and some extra 

 strong fighting had to be done to win it. It 

 was accomplished by proving the following 

 principles so that the court, like all others, 

 had been first convinced by the prima 



