Columbia River — Hanford Reach

About

Between Priest Rapids Dam and Richland, 51 miles of free-flowing Columbia River cuts through the Hanford Reach National Monument at an average of 120,000 CFS — the last undammed stretch of the Columbia in the United States. The signature 15-mile section from Vernita Bridge to White Bluffs runs beneath towering chalk cliffs that give this reach its name, while the upper 20 miles from Priest Rapids Dam maintains Class I-II character in big water that demands respect at any flow. Optimal range spans 80,000 to 200,000 CFS, tracked at USGS gauge 12472800, though even low flows here dwarf most western rivers. The Hanford Nuclear Reservation's closure created an accidental wilderness — sagebrush steppe and riparian corridors now protected as a National Monument, with Wild & Scenic study status pending. Columbia Kayak Adventures operates guided trips through these protected waters. Below the White Bluffs, the final 16 miles to Richland widen and slow as the river approaches the Tri-Cities confluence.