A soft autumn glow illuminated a vast expanse of Columbia River canyon as we pulled off the highway into a small gravel parking area in southeastern Washington between the Tri-Cities and Walla Walla, Washington. Two Red-tailed Hawks soared along the sage and juniper encrusted ridge-line, welcoming us to this enchanting place. A Prairie Falcon streaked by, stirring up a flock of Juncos. We crossed through a break in the barbed wire fence and hiked the ¼-mile trail through Sagebrush and Rabbit Brush to the captivating double basalt columns looming above: the Twin Sisters.
A sign near the Twin Sisters contains the following legend (abbreviated version): “The large basalt pillars in front of you are actually two Cayuse Indian sisters…For many years Coyote lived happily with the sisters, but after a while he became jealous of them. Using his supernatural powers, coyote changed two of his wives into basalt pillars.”
More than 12,000 years ago, pre-people, there were a series of massive floods through Wallula Gap. According to Don Snow, Senior Lecturer of Environmental Studies at Whitman College “Wallula Gap had formed a temporary hydraulic dam, partially stopping the largest floods the planet has ever seen…from the super-fast flow that had drained glacial Lake Missoula hundreds of miles away. “
These floods occurred multiple times. They filled Wallula Gap up and over the 1,000 foot level, not only with water, but also with giant icebergs, often serving as rafts for huge boulders that were later deposited as glacial erratics. The currents were estimated to be between 40 and 50 mph. It is hard to imagine floods of this scale, but their evidence is imprinted on the landscape.
Wallula means a place where a small stream runs into a larger one: in this case where the Walla Walla River meets the Columbia River. Once a thriving trading post, Fort Walla Walla was located here. The nearby town of Wallula was once a major hub of rail and shipping commerce. Today it is a sleepy 200+ person town.
This is a spectacular landscape with a spectacular story. Who knew? Thanks to a recent book Where the Great River Bends – A Natural and Human History of the Columbia at Wallula, edited by Robert J. Carson, a Whitman College geology professor, more people are discovering it. Carson continues to bring scores of students to the Gap to study its geologic and other natural wonders.
Currently, Wallula Gap is one of 17 National Natural Landmarks in the state of Washington. It will likely become part of the new Ice Age Floods National Geologic Trail. Whitman College recently established a biological field station nearby. But the site also suffers from vandalism and graffiti. As Carson writes in his book “Graffiti on the Twin Sisters is a problem; more visitor use, including rock climbing, would decrease vandalism.”
Could Wallula Gap be a candidate for a National Monument? It is certainly worthy.
