Study Information

John Redmond Reservoir, in east-central Kansas, has a primarily agricultural drainage basin of about 3,015 square miles (mi2 ) that includes the Cottonwood and upper Neosho Rivers. The reservoir was constructed during 1959 through 1964 for flood control, water supply, and recreation. Surface water is the primary source of water in the Neosho regional planning area, which includes the Cottonwood and Neosho River Basins and accounts for 86 percent of the total reported water use.

John Redmond Reservoir has a total storage capacity of 816,795 acre-feet (acre-ft) at maximum pool level; about 505,855 acre-ft are available for storage of floodwater. John Redmond Reservoir is losing storage capacity more rapidly than most other Federal reservoirs in Kansas. John Redmond Reservoir was designed using an estimated sedimentation rate of 404 acre-feet per year. Previously estimated reservoir sedimentation rates exceeded that rate by 22-116 percent.

Reservoir sedimentation reduces storage capacity and can have lasting effects on flood control, public water supply, habitat for fish and wildlife, and recreation. The U.S. Geological Survey (USGS), in cooperation with the Kansas Water Office, has monitored water quality on the Cottonwood River (upstream from the reservoir) and the Neosho River (upstream and downstream from the reservoir) since 2007. Water-quality monitoring and discrete sampling was used to develop and update regression models establishing relations between continuously monitored turbidity and suspended-sediment concentrations. These models are useful for evaluating concentrations of suspended-sediment to compare with water-quality criteria and for computing loads and yields to assess yields and fluxes.

Previous Study Information

The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, initiated a study to characterize suspended-sediment loading to and from John Redmond Reservoir from February 21, 2007, through February 21, 2008.
During a study period with approximately average flow conditions, John Redmond trapped 91 percent of the approximately 1,120,000 tons of sediment transported to the reservoir. Ninety-nine percent of incoming sediment load was transported during nine storm events which occurred during 25 percent of the study period.

Historic (1964-78) sediment sampling up and downstream from John Redmond Reservoir was compared with current (2007-2008) results to determine whether current streamflows are transporting more or less sediment. Although differences in sediment transport were statistically insignificant at sites upstream from John Redmond, significantly less sediment is transported immediately downstream from John Redmond than during historic, post-reservoir conditions. Results from this study can be used by natural resource managers to better plan for John Redmond Reservoir to support industrial, municipal, and recreational uses into the future.

"The Kansas Water Office has partnered with the Corps of Engineers to explore ways to extend the water supply storage capacity at John Redmond Reservoir. This USGS study will aid in the calibration of the watershed sediment model being developed by Kansas State University as a part of this effort and provide an improved understanding of the sediment delivery to and trapping efficiency of John Redmond Reservoir" -- Chris Gnau of the Kansas Water Office

External Links

• Sediment Monitoring in the Neosho and Cottonwood River Basins (usgs.gov).
• The report for the previous study is now available online.