How calm the Columbia River looks. Fifteen thousand years ago, during the Ice Age Floods, it wasn’t quite like this. At that time the Columbia was flowing at the top of the basalt cliffs seen in the distance. The West Bar shown in the middle of this image is comprised of gravel. rock, and other sediments. It was part of the backwater created as the Columbia raged toward the left and then back down through the gorge. The surface of the bar is covered with giant ripples around thirty feet high.
This image was taken above Crescent Bar looking southwest.