RIPARIAN REMEDIATION AND MANAGEMENT OF THE NEOSHO RIVER VALLEY IN NORTHEASTERN KANSAS

The high load of suspended sediments in Kansas rivers and reservoirs has raised many concerns about the quality of the state’s water supply. Erosion originating in pastures, croplands, gullies and channel-banks accounts for the majority of the suspended sediment load. Pasture and cropland adjacent to river and stream banks without riparian buffers increase de-stabilization allowing for bank deterioration and contribute non-point source pollutants such as fertilizers, pesticides and fecal matter. Determining high-risk areas along rivers and tributaries for either riparian remediation or bank stabilization is part of our research. Using GIS technology with present day and historical aerial images, high risk areas of the river channel can be readily identified. Temporal studies made over a 60-year span of river channel migration indicate a direct relationship to increased suspended sediment loads. In east-central Kansas, John Redmond Reservoir and the Flint Hills National Wildlife Refuge (FHNWR) on the Neosho River are case-study areas. Over 30 years members of the U.S. Corps of Engineers and the FHNWR have struggled with the removal of large woody debris carried downstream by flood events on the Neosho River. A massive logjam starting at the rivers entry point to the reservoir focused public attention on the issues involved for managing the reservoir. Ground truth observations indicate a rise in the Neosho River’s normal water level due to the logjam. Low-height blimp aerial photography used after a flood event on the Neosho River illustrated sediment plumes from an adjacent field not far from the reservoir. Issues of concern which have developed are; decreased water storage capacity of >50% in the reservoir, reduced water flow, increased algae blooms, and declining water quality.