Looking out over the Hetch Hetchy Reservoir from on top of the O'Shaughnessy Dam, Yosemite National Park - California. Wapama Fall can be seen in the distance (center).
Water being drained from the Hetch Hetchy Reservoir behind the O'Shaughnessy Dam, Yosemite National Park - California.
Plaques commemorating the original construction of the O'Shaughnessy Dam from 1915-1922 (left), increasing height in 1938 (center), and Canyon Power Tunnel from 1962-1964 (right).
