List of rapids of the Columbia River

Download coordinates as: Download coordinates as: 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".

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.

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.