Upstream end of diversion tunnel after spring flood.

At downstream end of diversion tunnel after spring flood. Employees are working diligently to pump out the water.

Looking into diversion tunnel. (Rig. Inside) Note on back: "Inside diversion tunnel, looking down 30 ft. tunnel to the power house. Tunnel lined with steel. Air hammer scars on the perimeter. Arizona side. - W. A. Davis, 1992."

View building the diversion tunnel. "Jumbo in place - trimming hole." W.A. Davis, 1992

Outside of diversion tunnel No.2; shows side walls and jumbo inside. Notes with image: "The side wall forms were then put in there place and section after section side wall poured. Center is slip form. 1st pour on the side walls. Jumbo forms in place. Duck holes-doors used for sequential pours were on the jumbo. - W. A. Davis, 1992."

Placing concrete liner in diversion tunnel, 3 feet thick. Note on back of image: "Photo taken at night. Pour lower invert first, then side walls, then ceiling. Covered walls with asphalt to prevent rapid drying of concrete. Jumbo probably sparying asphalt in this photo. Rails visible that jumbo rode on. - W. A. Davis, 1992."

Diversion Tunnel No. 3 nearly completed. Sept. 1, 1932. "Asphalt visible on ceiling. Fill on Floor & rails have to be removed prior to use for water diversion. Tunnel is completed except for fill removal." W.A. Davis, 1992