Troutdale History Night – The Bridge of the Gods
The Bridge of the Gods: Folklore, Forests, and Floods presented by Jim O’Connor
In the heart of the Columbia River Gorge 30 miles east of Edgefield, the 1800-feet-long steel truss bridge spanning the Columbia River at Cascade Locks is known as the Bridge of the Gods. But this modern name derives from a much larger Bridge of the Gods that covered the Columbia River in about 1450 AD. This earlier “bridge” was not really a bridge, but a blockage, the result of a huge landslide, known as the Bonneville Landslide, which headed on Table Mountain on the Washington side of the river and cascaded downward, filling the Columbia River valley with 5 square miles of debris up to 400 feet thick.
The Bonneville Landslide almost certainly gave rise to the Native American legend of the Bridge of the Gods. Oral histories of the region indicate that the Native Americans “could cross the river without getting their feet wet.” Also recounted was “that the river was dammed up at this place, which caused the waters to rise to a great height far above and that after cutting a passage through the impeding mass down to its present bed, these rapids first made their appearance.” “These rapids” became known as Cascade Rapids, sometimes called the Cascades of the Columbia. The rapids were the remnant debris of the landslide dam.
After blockage by the Bonneville landslide, the Columbia River formed a great lake behind the debris dam. Sometime after overtopping, the Columbia River cut – cataclysmically — through and around the southern edge of the landslide mass. But the downcutting was not complete, and large rocky debris too big to be carried away by the river remained, creating the set of foaming rapids, first mapped by Lewis and Clark as “The Great Shoot.” Cascade Rapid was drowned by the 1938 completion of Bonneville Dam.
About the Speaker
Jim O’Connor is a Research Geologist at the U.S. Geological Survey in Portland, Oregon, where he has been stationed since 1996. His primary research focus is landscape evolution in the Pacific Northwest. He majored in Geological Science at University of Washington and earned M.S. and Ph.D. degrees at University of Arizona.
Free Admission, all ages welcome!
6:30pm (Doors open at 5pm),
Arrive early, seats fill up fast.
Blackberry Hall @ McMenamins Edgefield
2126 SW Halsey Street, Troutdale, OR 97060
McMenamins.com/History