The dam was constructed in the early 1900s as part of the Newlands Reclamation Act, designed both for hydroelectric power and irrigation. It predates the O’Shaughnessy Dam at Hetch Hetchy. These dams obviously have a huge impact on the land.
Trucks look like matchbox cars at the bottom
Roosevelt Dam was renovated in 1989, increasing the capacity of the lake by 20%.
Despite the fact that the Roosevelt Lake Bridge is the “longest two-lane, single-span, steel-arch bridge in North America,” we were the only ones admiring it (or driving on it).
You can read more about the history of the Dam and bridge here: http://www.usbr.gov/lc/phoenix/projects/rooseveltdam/rdhistory.html.