Channel stability of the Neosho River downstream from John Redmond Dam, Kansas

The stability of the Neosho River channel downstream from John Redmond Dam, in southeast Kansas, was investigated using multi-date aerial photographs and stream-gage information. Bankfull channel width was used as the primary indicator variable to assess pre- and post-dam channel change. Five 6-mile river reaches and four stream gages were used in the analysis. Results indicated that the overall channel response to the altered streamflow regime and sediment load introduced by the dam has been minor. Aside from some localized channel widening, there was little post-dam change in bankfull channel width. The lack of a pronounced post-dam channel response may be attributable to a substantial reduction in the magnitude of the post-dam annual peak flows in combination with the resistance to erosion of the bed and bank materials. Also, the channel may have been overwidened by a series of large floods that predated construction of the dam.