Zion National Park: Virgin River Rip Rap – Washington County UT

Description

Several revetments (rock flood walls) along the Virgin River in Zion National Park’s main canyon were installed by the Civilian Conservation Corps (CCC).  Unfortunately, this kind of flood control work was a hopeless endeavor and most of the revetments were washed-out. Where they remain, however, they channelized the river, which is even worse because it has altered the deposition regime of the river and affected the ecology of the flood plain through the bottom of the canyon.