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, the largest town on the river, 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 north of the Iowa-Missouri border, and the river travels south, passing
Bradyville on its east, before entering Missouri. Continuing from the Iowa border in
Nodaway County, Missouri, the river travels south a mile west of
Burlington Junction where it intersects
US 136. Continuing southerly, the river passes west of
Quitman and east of
Bilby Ranch Lake Conservation Area before crossing
Missouri Route 46. Afterward, the river passes by
Skidmore and passes under
Missouri Route 113 where it quickly becomes the border between Nodaway County and
Holt County. Continuing southerly, it passes between
Maitland to its east and
Graham to its west, and reaches the
tripoint with
Andrew County. The river remains the boundary between Holt and Andrew counties to the Missouri River. The Nodaway River then passes through
Nodaway Valley Conservation Area, where it is
channelized and flows steadily until
Interstate 29. Afterward, it passes west of
Honey Creek Conservation Area and east of
Monkey Mountain Conservation Area, and flows into the
Missouri River Valley by
Nodaway and joins the Missouri River. Elevations in the Nodaway system range from just under above sea level at the source of the Middle Nodaway, to at the beginning of the main stem, to at its mouth on the Missouri River at the community of Nodaway in
Andrew County, Missouri. The Nodaway River is a
sixth order river with a basin area of . The
Platte River basin is to the east and the
Grand River and
Des Moines River basins to the northeast, with the latter defining the boundary between the Missouri River and Mississippi River basins. The west side is bound by the
Tarkio River basin and in the northwest by the
Nishnabotna River basin. The Nodaway River basin is prone to extensive flooding and can contribute as much as 20% of the flood crest of the Missouri River near its mouth. At
Graham, Missouri its normal flow is . But during the
Great Flood of 1993 the river was flowing at Graham. ==Tributaries==