Hurricane Camille, Nelson County, VA 1969

From Wikipedia:

On the night of August 19-20, 1969, Nelson County was the site of disastrous flooding due to Hurricane Camille. The hurricane had come ashore on the Gulf Coast 2 days earlier, and weakening over land, had traveled north and then stalled on the eastern side of the Blue Ridge Mountains dumping a record quantity of 27 inches (690 mm) of rain, mostly within only a 3 hour period. The rainfall was so heavy there were reports of birds drowning in trees and of survivors who had to cup their hands around mouth and nose in order to breathe through such a deluge.

As many people slept unaware, the ensuing flash floods and mudslides killed 153 people, 31 of them from Tyro and Massies Mill alone. Across Nelson County, 133 bridges were washed out, while some entire communities were under water. In the tiny Davis Creek community, 52 people were killed or could not be found; only 3 of 35 homes were left standing after the floodwaters receded. The bodies of some people were never found; others washed as much as 25 miles (40 km) downstream along the creeks and rivers. The entire county was virtually cut off, with many roads and virtually all bridges, telephone and electric service interrupted.