Warning sign before entering the wash that the guide will take you Upper Antelope Canyon. On July 18th 2011 a huge flash flood came through the canyon, flowing all the way in the wash till eventually going underneath Hwy. 98 and dropping into Lower Antelope Canyon before reaching Lake Powell.

Flood water in Antelope Wash before going underneath Hwy. 98 and dropping into Lower Antelope Canyon.

This flash flood created a wall of mud and debris from side to side in the wash bringing tree trunks and boulders with it as well as undermining the banks of the wash.

Flood water in Antelope Wash before going underneath Hwy. 98 and dropping into Lower Antelope Canyon.

Flash flood before going underneath the bridge on Hwy.98

Flash flood before going underneath the bridge on Hwy.98

Flash flood before going underneath the bridge on Hwy.98