172 



THE IBEIQATION AGE. 



parts of sand. The cost of preparing the channel and 

 lining was 18 cents per lineal foot, or 2.88 cents per 

 square foot. 



The San Jacinto Water Company, also in Kiverside 

 county, has its canal lined in the same manner as the 

 Gage canal; the length of the canal is 11 miles, the 

 bottom width is 3 feet, the depth 2% feet, and the side 

 slopes 1 on 1. 



That this type of lining has been successful there 

 is no doubt. Mr. Irving, former engineer for the Gage 



with masonry of the type "a" or "b," previously de- 

 scribed. The Gage canal has used masonry very sim- 

 ilar to class "a" for the lining of canals when in fill or 

 made ground. This masonry is about 6 inches in thick- 

 ness and is composed of building stone laid in mortar 

 whose ingredients are one part of Portland cement, three 

 parts of fat lime, and twenty parts of sharp sand. All 

 external surfaces exposed to the action of the water 

 are coated with % inch of cement mortar, composed of 

 one part of cement to three parts of sand. The cost 



Fig. 9 Unlined canal near Lemoore, showing vegetation. 



Canal Company, states in his report that after a test of 

 ten years the lining more than justified their expecta- 

 tions. The cost of repairs after four years' use was 

 very small, less than y 2 of 1 per cent of the capital cost 

 in four years. 



That there are conditions under which this linnig 

 will not be entirely satisfactory has also been demon- 

 strated as follows : 



1. For water channels constructed in heavy adobe 

 soil, subject to heaving, it has cracked badly. This is 

 noticeable in parts of the canal of the San Jacinto 

 Water Company. 



of this class of work, which is very similar to class "a," 

 but not so thick, is about ll 1 /^ cents per square foot. 



The thin plaster lining is subject to rupture where 

 gophers or squirrels burrow behind it, or under it, as 

 the lining has not sufficient strength ; also if storm water 

 washes out some of the back filling. 



It is probable that this kind of lining would not 

 resist the climate of a country subject to very cold 

 weather, in which case the stronger lining with proper 

 drainage to prevent the accumulation of water behind 

 the lining would be needed. 



Fig. 10 Unlined canal near Lemoore, showing vegetation. 



2. For water channels built in fills, where the 

 ground is subject to settlement. 



A better construction in this case is to line the canal 



HEAVY ROAD OIL. 



The instances where road oil has been used for 

 canal or reservoir lining are few. The only example 



