432 Transactions of the 



with the canal south from tho Cottonwood, crossing that stream, con- 

 tinuing its course to an intersection with the San Joaquin, a distance of 

 about nine miles. For the purpose, of constructing the canal a careful 

 exploration was made by Mr. Alfred Poett, civil engineer, in eighteen 

 hundred and seventy-one, of the Fresno Kiver, following its course to 

 the headwaters; also of Snow Creek and other streams, with a view 

 of adding to the present supply given by the Fresno. The examination 

 of the Fresno, about three miles above the present railroad crossing, 

 showed by borings taken, that a large stream of water filtered through 

 its bed, even during the driest season. In view of this fact it was thought 

 worth while to construct a tight dam, made solid and well, down into 

 the hard-pan strata under the sand, thereby holding the water, in the 

 hope thus to secure water enough for irrigation, not only during the 

 Spring, but also enough during the Summer, for a second crop. The 

 latter part of the object aimed at has not been secured. Although the 

 tight dam has been built deep below the sands of the river bed, the 

 water continues to flow through these stratas, showing that it makes its 

 way around the ends of the dam. 



In November, eighteen hundred and seventy-two, the present works 

 were commenced, too late in the season for favorable work. The Win- 

 ter rains not only interfered with the progress of the dam, but tested 

 its stability b}* a very trying test. The dam and head-gntes are now 

 completed, also the canal from the Fresno to the Cottonwood, the final 

 finishing touches having been given in the latter part of July, when the 

 three distributing ditches were also completed to the railroad — a dis- 

 tance of two miles for each, or ten miles of main and distributing canal 

 in all. 



The dam is a timber structure, three hundred and eleven feet long, and 

 raisins: the water six feet above original level, constructed of two rows 

 main piles from twenty to thirty-five feet long, planted ten feet apart, 

 the points firmly imbedded in a stratum of clay. Between the main 

 piles is a double row of four-inch sheet piles. The space between the 

 two rows of piling is filled in solid and planked on top. The action of 

 the water during freshets on the river bed below the dam is guarded 

 against by a timber " apron " of four-inch planking — an incline set to 

 receive the water as it tumbles over the dam and shed it off on its course 

 down stream, upon a thick layer of loose rock work. When the water 

 reaches the top of the dam it is backed up, forming a lake one mile long 

 by five hundred feet wide, with an average depth of five to six feet. 

 The water is turned into the canal, by the opening of six gates, into a 

 flume or timber box thirty feet wdde. Through this fluming it is turned 

 into the canal. 



This work is constructed with an uniform width at the bottom of 

 twenty feet. The sides rise on a slope of one foot vertical to two feet 

 horizontal, to a height of eight feet, carrying six feet of water. This is 

 the waterway or channel which is expected to flow full of water. The 

 water at the surface is therefore forty-four feet wide. The banks are 

 carried up higher, on a steeper slope, and on the top are four and a half 

 feet wide. The canal is taken from the river at the highest point neces- 

 sary to convey water to the irrigable ground. This point is in a ridge 

 of "hog wallow." The cutting through this ground is quite deep, and 

 at the river the canal work has the imposing appearance of a railway 

 cutting. It is run on a grade of six inches to the mile, which will give 

 a flow of the water at a rate of one and a quarter miles per hour, and 

 will discharge, when running full, three hundred and sixty cubic feet of 



