Palouse River

Palouse River
Several miles downstream from its fork in Colfax; looking west in 2007
Palouse River's mouth in Washington
Location
Country	United States
State	Washington, Idaho
County	Franklin, Whitman, Adams, Latah
Physical characteristics
Source	Rocky Mountains
• coordinates	46°58′07″N 116°27′31″W / 46.9685°N 116.4587°W / 46.9685; -116.4587[1]
Mouth	Snake River
• coordinates	46°35′24″N 118°12′55″W / 46.59000°N 118.21528°W / 46.59000; -118.21528[1]
• elevation	541 ft (165 m)[1]
Length	167 mi (269 km)
Basin size	3,303 sq mi (8,550 km2)[2]
Discharge
• location	river mile 19.6 at Hooper[3][4]
• average	599 cu ft/s (17.0 m3/s)[3][5]
• minimum	0 cu ft/s (0 m3/s)
• maximum	33,500 cu ft/s (950 m3/s)

The Palouse River is a tributary of the Snake River in Washington and Idaho, in the northwest United States. It flows for 167 miles (269 km)^[6] southwestwards, primarily through the Palouse region of southeastern Washington. It is part of the Columbia River Basin, as the Snake River is a tributary of the Columbia River.

Its canyon was carved out by a fork in the catastrophic Missoula Floods of the previous ice age, which spilled over the northern Columbia Plateau and flowed into the Snake River, eroding the river's present course in a few thousand years.