Reservoir Restoration & Zebra Mussel Treatment

Location: Osage City, Kan.

Client: City of Osage City

Completion Date: 2011 - ongoing

In early 2012, Osage City, Kan., experienced loss in pressure from the 24-inch main waterline from Melvern Lake, the primary source of drinking water for the city. It was determined that the waterline was plugged by zebra mussels. At that time the Osage City Reservoir became the main source of water for the more than 5,000 users in the service area for more than 75 days pumping more than 40 million gallons of water from the reservoir, drawing the water level down seven feet within 3 feet of the intake. The reservoir was nearly pumped dry. The Melvern waterline was flushed and sanitized to kill off remaining zebra mussels and put back on line.

In May 2012, the city was awarded $1.135 million grant from the Kansas Department of Agriculture, Department of Conservation to improve and enhance the dam and spillway and restore capacity, and improve the overall water quality in the Osage City Reservoir. In addition, the city will replace the existing Melvern waterline and install a treatment system for zebra mussels.

Burns & McDonnell has been retained by the City of Osage City to engineer, design, permit and oversee construction of the lake restoration project and the installation of the waterline and treatment system project.

  • Grant writing
  • Bathymetric and sediment thickness mapping
  • Sediment and water collection
  • Laboratory analysis
  • Evaluation of dredging alternatives
  • Land use assessment
  • Aquatic habitat and fisheries assessment
  • Engineering and design
  • Cost estimating and scheduling
  • Public involvement
  • Environmental permitting (Section 401 and 404, NPDES, water use)
  • Construction monitoring

In 1923 and 1939, the dam and spillway for the Osage City Reservoir were modified to raise the permanent pool levels by increasing the height of the dam and spillway by 7 feet due to a reduction in water supply capacity caused by sediment loading. The reservoir later withstood the historic floods of 1951. The flooding was followed by two years in which the City was able to mechanically excavate approximately 160,000 cubic yards of sediment, increasing the water supply capacity.

In 2012, Melvern Lake was the main source of drinking water for the city, and the Osage City Reservoir is now a supplemental source due to increased needs in the service area. Over the past 50 years, the Osage City Reservoir capacity and water quality have decreased because of sediment loading and non-point source run-off from agricultural practices.