THE IRRIGATION AOE. 



209 



Lining of Ditches and Reservoirs 

 to Prevent Seepage Losses. 



By Prof. B. A. Etcheverry. Berkeley, Cal. 



(Continued.) 



The oil used was crude petroleum from the Sunset 

 District southwest of Bakersfield and contains a large 

 percentage of asphaltum. Its specific gravity is ll 1 /^ on 

 the feeaume scale. This oil when cold will not run 



When examined in May, 1906, about seven months 

 after the application of the oil, there was no vegetation 

 in this part of the canal, while other parts of this same 

 canal which had received no oil and had been cleaned 

 two weeks previously showed a growth of vegetation. 

 The contrast is very striking and clearly shows the 

 value of oil in preventing the growth of aquatic plants. 

 Not only was this part of the canal free from vegeta- 

 tion, but it was only about one-third full, while the 



Fig. 12. Ivanhoe Reservoir (Near Los Angeles), Lined with Oil. 



freely. .It was used hot and sprinkled with an ordinary 

 road sprinkler. The ditch had been previously cleaned 

 of all vegetation and allowed to dry. The road 

 sprinkler was driven first on the bottom of the ditch and 

 then on the banks. The oil was applied at the rate of 

 11/2 gallons per square yard. The oil was then thor- 

 oughly harrowed in until it was well mixed with the 

 soil, which was very sandy. 



canal full of weeds had to be full to carry the same 

 amount of water. 



An objection might be made to the use of oil for 

 canal lining because of the fear that the oil might be 

 carried to the fields in sufficient quantity to injure the 

 crops. Mr. McLaughlin states that in this case they had 

 no trouble from this source. 



An example of the use of oil for lining reservoirs 



/ 



>" 



7 





K/ 



tM 



6 O 7 ' 



7 



/o 



7\ 



Fig. 13. Position of Experimental Trenches at Modesto. 



