List of rapids of the Columbia River
This is a list of rapids of the Columbia River, listed in upriver order. The river flows through Canada and the United States. Almost all of these rapids are now submerged in the reservoirs of dams. The list is not exhaustive; there were numerous minor rapids and riffles, many of which were never named.
The 70 mile stretch between Priest Rapids and the mouth of the Snake River (the Hanford Reach) "has the slowest current of any part of the Columbia above The Dalles".
The portion of the river between Monaghan Rapids and Foster Creek Rapids was regarded as particularly hazardous. An 1893 report by the Army Corps of Engineers described the river from Monaghan Rapids to the foot of Foster Creek Rapids as "very swift and studded with rocks, and taken all in all will be found an extremely hard and dangerous if not absolutely impassable portion of the river to navigate". Over the 45 miles (72 km) from Monaghan to Foster Creek the river fell 171 feet (52 m) at low-water. Over the 10 miles (16 km) between Mah-kin Rapids and a point three miles below Parson Rapids the river fell 41 feet (12 m) at low water. The portion from White Cap Rapids to Eagle Rapids was once known as "Nespilem Canyon". The Corps' 1893 report said that over the worst 3 miles (4.8 km) stretch the river fell 22 feet (6.7 m) at low-water and 24 feet (7.3 m) at high-water, and that the speed of the current at low-water was about 10 miles per hour (16 km/h). On the possibility of navigation the Corps was pessimistic: "The fall of the river here is so great that it is certain that no system of rock removal could make the river sufficiently navigable to justify the danger and risk necessarily incurred in running boats on it."
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