Grandma's Postcards
Boulder Dam - Upstream Face and Intake Towers from Arizona Side
The waters of the Colorado River which form Lake Mead, have been impounded behind Boulder Dam until now only 120 feet of the sheer 600 foot upstream face is above the water surface.  When the water nears the crest it will flow off through spillways which drain into huge 50-foot tunnels around the dam and back into the river downstream.