Lake Lewis
Videos
Lake Lewis was a large transient lake in the Pacific Northwest region of North America, formed by periodic Missoula Floods along the Columbia River paleocourse between 21,000 and 16,000 years ago.
This figure shows four profiles of Lake Lewis at various flood levels. It illustrates that the lake back flooded several valleys in which the Touchet Beds were found.
Looking to the West across the Wallula Gap.
Touchet beds in the "Little Grand Canyon" near Lowden in the Walla Walla valley. Note distinct layers.
Cluster of erratics on Red Mountain shown in the foreground; these were trapped in glacial ice and "rafted in" on the flood of Lake Lewis. In the background the native basalt, which covers the rest of the mountain ridge, is visible.
Rattlesnake Mountain is a 3,531 ft windswept treeless ridge overlooking the Hanford nuclear site. Parts of the western slope are privately owned ranchland, while the eastern slope is under the federal
The view of Rattlesnake Mountain from the Horn Rapids Golf Course in Richland.
