The Nodaway River is a river in southwest Iowa and northwest Missouri. Etymology The river's name (as "Nodawa") first appears in the journal of Lewis and Clark, who camped at the mouth of the river on July 8, 1804, but who provide no derivation of the name. The name is an Otoe-Missouria term meaning "jump over water". The term would be spelled today in full as Nyi At'ąwe (nyi (water) + a- (on) + t'ąwe (jump)) and would be contracted in regular speech as Nyat'ąwe or Nat'ąwe. History Lewis and Clark camped at the river's mouth on Nodaway Island on July 8, 1804, by Nodaway, Missouri, on the border of Holt County, Missouri and Andrew County, Missouri and took note of the river. Lewis and Clark liked the spot enough that they recommended it for the winter headquarters of Astor Expedition of 1810–12 that discovered the South Pass in Wyoming through which hundreds of settlers on the Oregon Trail, California Trail, Mormon Trail were to pass. The river is navigable only by shallow fishing and row boats although steam ships navigated just inside its mouth. The river was the primary route for white settlers including Amos Graham and Isaac Hogan following the Platte Purchase of 1836 which opened northwest Missouri for settlement. Nodaway County, which derives its name from the river, was by far the biggest county in the purchase and the fourth largest in the state of Missouri. Description Major tributaries in the Nodaway River basin are Seven Mile Creek, West Nodaway River, East Nodaway River, Middle Nodaway River, Clear Creek, Mill Creek, Elkhorn Creek, and Arapahoe Creek. The biggest town on the river is Clarinda, Iowa. The Nodaway begins near Shambaugh, Iowa at the confluence of the East and West Nodaway rivers. The West Nodaway River rises northeast of Massena in eastern Cass County, Iowa, and flows south-southwest past Villisca and Clarinda to its junction with the East Nodaway. The East Nodaway River rises just west of Orient in Adair County and flows southwest past Prescott, Corning, Brooks, and Nodaway to its confluence with the West Nodaway. The Middle Nodaway River rises in Adair County south of Casey and flows southwest past Greenfield, Fontanelle, and Carbon to join the West Nodaway just below Villisca, Iowa, above the West Nodaway's juncture with the East Nodaway. The East and West Nodaway join to form the Nodaway River four miles (6