Project Overview

Cheney Reservoir was constructed by the Bureau of Reclamation, U.S. Department of the Interior, between 1962 and 1965 to provide downstream flood control, wildlife habitat, recreational opportunities, and a reliable municipal water supply for the city of Wichita, Kansas. The city of Wichita acquires about 70% of its daily water supply (2005) from Cheney Reservoir and provides water to about 400,000 residents in the Wichita area. The Cheney Reservoir watershed includes an estimated 933 square miles of contributing drainage area from the North Fork Ninnescah River and associated tributary streams. The North Fork Ninnescah River is the major inflow to Cheney Reservoir and accounts for approximately 70% of the water flowing into the reservoir.

Cyanobacterial blooms in drinking-water supplies and recreational water bodies raise ecologic, economic, and public health concerns. Because of increased treatment costs and customer dissatisfaction with malodorous drinking-water, cyanobacterial production of taste-and-odor compounds is of particular concern to drinking-water suppliers. Taste-and-odor episodes in Cheney Reservoir during the early 1990’s prompted water-quality studies in both the reservoir and watershed with a goal towards improving water-quality.

The U.S. Geological Survey began cooperative studies of the Cheney Reservoir watershed with the city of Wichita in 1996. Initial studies determined the chemical loading into and out of Cheney Reservoir, changes in reservoir sediment quality over time, and chemical loading from various sub-basins within the watershed. Phosphorus and sediment were identified as the major contaminants in Cheney Reservoir, although salinity, metals, selenium and pathogen indicator bacterial (fecal coliform) also were of concern. In addition, reservoir sediment studies documented an increasing trend in phosphorus concentrations over time. More recent studies (2000-2006) have focused on real-time estimation of water-quality constituent concentrations and transport from the watershed and the description of in-reservoir conditions that may result in the production of algal blooms and taste-and-odor compounds. Models using variables measured by real-time water-quality monitors successfully were developed to provide hourly estimates of the concentrations nutrient, sediment, and taste-and-odor compounds. Ongoing studies at Cheney Reservoir will refine the relations between reservoir and inflow conditions and taste-and-odor occurrences. The city of Wichita plans to use these models, along with other variables measured in real time, to aid in the management of the resource and decrease water-treatment costs.

Related Links

• Continuous Water Quality
• Cyanobacterial Taste-and-Odors and Toxins
• Lake Olathe Water Quality
• Lakes and Reservoirs
• Reservoir Sediment
• Cheney Lake Watershed, Inc.
• Equus Beds Recharge

For additional information, please write or call:

Jennifer Graham
U.S. Geological Survey
4821 Quail Crest Place
Lawrence, KS 66049-3839
Telephone: (785) 832-3511
Fax: (785) 832-3500
Email: jlgraham@usgs.gov