Bulletin 831, U. S. Dept. of Agriculture. 



Plate IV. 



Fig. !. — Diversion Dam, Washington Power Co., near Spokane, Wash. 



Built at the Little Falls plant in the form of an "L" to gain crest length 



Fig. 2. — Arched Type Spillway Dam, Pishkun Reservoir. Montana. 



Air intake tower shown in center of picture built to eliminate vibration due to vacuum. 



