Tarkio River

Tarkio River
Big Tarkio River
Lewis and Clark Expedition maps showing the Tarkio between Nishnabotna and Nodaway River
Location
Country United States
State Iowa and Missouri
CountyCass County, Iowa, Montgomery County, Iowa, Page County, Iowa, Atchison County, Missouri, and Holt County, Missouri
Physical characteristics
Source 
 • locationPleasant Township
 • coordinates41°11′38″N 95°03′45″W / 41.1938794°N 95.0624898°W / 41.1938794; -95.0624898
 • elevation1,300 ft (400 m)
MouthMissouri River
 • location
Union Township
 • coordinates
40°09′46″N 95°26′19″W / 40.1627768°N 95.438592°W / 40.1627768; -95.438592
 • elevation
866 ft (264 m)
Length81.1 mi (130.5 km)
Basin size508 sq mi (1,320 km2)
Discharge 
 • locationFairfax, Missouri
 • average223 cu ft/s (6.3 m3/s)
 • minimum3.3 cu ft/s (0.093 m3/s)
 • maximum1,350 cu ft/s (38 m3/s)
Basin features
ProgressionTarkio River → Missouri RiverMississippi RiverAtlantic Ocean

Tarkio River is a stream in southwestern Iowa and northwestern Missouri. It is a tributary to the Missouri River and is 81.1 miles long. The river is monitored by USGS at Fairfax, Missouri and is considered a major water source by the Iowa DNR.

The river passes rural areas and figures most prominently in the drainage system nears its mouth in management of Big Lake, Missouri and the Loess Bluffs National Wildlife Refuge, formerly known as Squaw Creek National Wildlife Refuge. Several streams and ditches in the Missouri River bottoms near its mouth contain the Tarkio name.