It appears that the beach was located along Boundary Channel with Columbia Island in the immediate background and Foggy Bottom across the main channel of the Potomac.
Submitted by Mike Cash on Sun, 07/06/2008 - 4:41am.
Good thing the photographer snapped the photo when he did. He prevented that guy from diving into into the rowboat. Of course, the downside is that he got stuck in mid-air like that for eternity.
Location
It appears that the beach was located along Boundary Channel with Columbia Island in the immediate background and Foggy Bottom across the main channel of the Potomac.