"1210 Looking upstream from a point near the presedimentation tank for the Boulder City water supply, during the recent high water, showing how the lower portals of the diversion tunnels have been protected with dikes of tunnel muck. May 26th, 1932.
1213 Constructing concrete coffer dams protected by muck fills in front of the lower portals of Diversion Tunnel No. 1—on the left—and No. 2—in the background. May 26th, 1932.
11116 Looking across the river toward the lower portals of Diversion Tunnel No. 3, which is protected by a concrete coffer dam and muck-fill dike. May 26th, 1932
12S8 Looking upstream toward the damsite from a point on the lower portal road. The lower portals of Diversion Tunnels Nos.
2, 3 and 4 can be seen. June 21st, 1932.