Us Army Corps of Engineers, Washington.
Lake Wallula, located in northeastern Oregon and southeastern Washington along the Columbia River, provides for water fun and relaxation. Up-lake near the junction of Highways 12 and 730 in Washington is an area known as Wallula Gap where the canyon narrows. Wallula Gap is the site of colorful Indian lore and is a place where interesting natural phenomena occurred during an ancient catastrophic event known as the Great Missoula Floods.
One mile east of Umatilla, OR, on Highway 730, and take the McNary Dam Road.