An image of expelled water creating a rainbow mist over the Colorado River on the downstream side of Hoover Dam in Black Canyon. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Working at Hoover (Boulder) Dam. The machinery shown include a water pump and power shovel. Note on back: "Not taken by W. A. Davis. That day the river came up and flooded tunnel on Arizona side. This shot shows pumpking the water out with a large sump pump. - James J. Hester, W. A. Davis' son-in-law, 1992."