Cofferdam (upper one), 1/4 - 1/2 mile upstream from Dam site. Dec. 25, 1932. Note on back: ""Electric Marion steam shovel on top of cofferdam. May have used shovel to lay down metal grating. - W. A. Davis.""
Caption at bottom right hand corner of image reads: "Upstream face of Boulder Dam showing intake towers and Arizona observation point." Boulder Dam was officially re-named Hoover Dam in 1947.