From the Bureau Of Reclamation website:
On top of the dam, two "Winged Figures of the Republic" dominate the Nevada approach, They are the work of sculptor Oskar J.W. Hansen, a Norwegian immigrant who was appointed a consulting sculptor by Secretary of the Interior Harold L. Ickes following a national competition.
Hansen said the 30-foot bronzed statues represented "that eternal vigilance which is the price of liberty."
Don’t forget to visit The Weekend in Black and White for some great black and white photography.