GATE STRUCTURES FOR IRRIGATION CANALS. 61 



WASTE GATE, LAKEVIEW IRRIGATION CO. CANAL, WYOMING. 



Plate XII, figure 1, shows a small waste gate set in the lower levee 

 of the canal. The crest of the solid wall is set as determined to be 

 the safe or desirable limit for a high-water line in the canal. Excess 

 water within limits, due to storms, passes safely off into the natural 

 drainage way to which the waste is connected. The side walls pre- 

 vent the erosion and washing out of the bank. 



WASTE GATE, TITRLOCK IRRIGATION DISTRICT, CALIFORNIA. 



The use of very cheaply-built wooden radial gates is brought out 

 in the view of a waste gate shown in Plate XII, figure 2. This gate 

 opens into a short canal with a capacity of 1,000 second-feet. This 

 great discharge is obtained with but three openings. Note that the 

 winches are located only a few inches above the tops of the shutters 

 and that no high gate standards are required. Although the water 

 in the main canal at the time this view was taken was nearly even 

 with the top of the gates, there was absolutely no leakage noticeable 

 at the sides of the shutters, the water in the foreground being either 

 seepage or that remaining from the last run of water through the 

 gate. Note also that this construction provides a crest waste way 

 which will pass off excess water in case the water level in the canal 

 reaches the tops of the gate shutters. 



The face of these gates is simple wooden planking, spiked to joists, 

 from w T hich the thrust of the water is carried by wooden arms to a 

 galvanized pipe axle extending completely across the openings. This 

 construction is shown in figure 14, page 50. 



o 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1914 



