The Nishnabotna River is known for great paddling in Iowa. The East and West Nishnabotna originate in Carroll County. However, it is in Pottawatamie and Cass Counties where under normal conditions the rivers are navigable.
The National Rivers Project labels the East Nishnabotna as Class II due to the sandbars you have to navigate around. They note that much of the character of the river has been stripped away due ot the channelizing in the early 1900s. It empties into the Missouri about 10 miles into Missouri.
Iowa Canoe Guide published in 2000: http://publications.iowa.gov/15395/1/Iowa%20Canoe%20Guide%202000.pdf
Flow gauge for East Nishnabotna
at Red Oak: https://waterdata.usgs.gov/monitoring-location/06809500/
at Atlantic: https://waterdata.usgs.gov/monitoring-location/06809210/. Minimum flow for paddling listed in Paddling Iowa (P. 50) is 150-200 cubic feet per second. Though at 150 cfs you can scrape in the riffles. Gradient is less than 2 feet per mile.
Flow gauge for West Nishnabotna
at Hancock: https://waterdata.usgs.gov/monitoring-location/06807410/. Minimum flow rate for paddling listed in Paddling Iowa is >125-400 cfs. Gradient is less than 2 ft/mi.
at Randolph: https://waterdata.usgs.gov/monitoring-location/06808500/.
Flow gauge for Nishnabotna at Hamburg: https://waterdata.usgs.gov/monitoring-location/06810000/
Friends of the West Nishnabotna: http://friendsofthewestnish.weebly.com/.
Outfitter located in Hancock/Botna Bend County Park: http://www.rubberduckoutfitters.com/.
Page created by Pottawatamie County: https://www.wattawayia.com/west_nishnabotna_trail/.
Trip report: https://paddling.com/paddle/trips/nishnabotna-river-iowa.