The East Nishnabotna River is a stream in the U.S. state of Iowa. It is a tributary of Nishnabotna River and is 123.6 miles. and is considered a major water source by the Iowa DNR.
Three notable towns are situated on the East Nishnabotna River: Atlantic, Red Oak, and Shenandoah. Shenandoah was said to have been named because of the resemblance of the East Nishnabotna river valley to the Shenandoah Valley in Virginia.
The stream is monitored at two places by USGS, Red Oak and Atlantic. The river's average discharge is 506 cubic feet per second at Red Oak. There was a stream gauge at Riverton from 2010 to 2016.
The East Nishnabotna rises in southwestern Carroll County and flows southerly to Hamlin in Audubon County and begins to travel beside US Highway 71. Five miles further south, the stream passes to the west of Exira, then turns southwest and passes Brayton and Lorah as it enters Cass County. It then continues past Atlantic, the largest town on its course, and is joined by Troublesome Creek and Turkey Creek thereabouts.
The stream parts from US 71 and continues southerly past Lewis and enters Pottawattamie County as it passes Griswold. The stream continues southerly and enters Montgomery County as it passes Elliott. Continuing another 10 miles south-southwest, it passes Red Oak, then 7 miles later, Coburg. As it enters Page County, it turns back more southwest and passes Essex, Shenandoah, and Riverton in Fremont County before joining with the West Nishnabotna River to begin the Nishnabotna River.