KU Connection - November 2007 - Reservoir sediment tackled at KU-hosted summit

Governor, officials and researchers tackle reservoir sediment at KU-hosted summit

A decades-long buildup of sediment across Kansas’ public reservoirs has created a little-known crisis in the state.

Today more than 60 percent of Kansans face potential problems with the quality of their drinking water—such as tastes described as “musty,” “fishy” or “earthen.” In the meantime, ever-increasing silt threatens reservoirs’ usefulness for flood control, irrigation and recreation.

On Oct. 17, KU hosted a “Kansas Reservoir Summit” organized by the Kansas Water Office to address this urgent situation. The event brought together Gov. Kathleen Sebelius, governmental agencies, researchers and businesspeople to discuss the problem of reservoir sedimentation.

“The siltation in Kansas reservoirs has been off the radar of many people,” said Mark Jakubauskas, associate research professor with the Kansas Biological Survey and team leader of the Applied Science and Technology for Reservoir Assessment initiative at KU. “But the Kansas Water Office realizes that this is a major issue that affects Kansas citizens economically and physically. Without water, we’re in a lot of trouble.”

In Kansas, Jakubauskas said, water quality trouble in part traced to silt has struck Wichita’s Cheney Lake and Lawrence’s Clinton Lake. In 2003, the communities of Marion and Hillsboro were forced to truck in drinking water because of quality problems with water from Marion Lake.

Currently, the Kansas Biological Survey’s ASTRA group is working under a $165,000 contract with the Kansas Water Office to map four federal and four smaller reservoirs. In addition to satellite imaging and a 24-foot pontoon boat equipped as a sediment-coring platform, the team employs state-of-the-art bathymetric mapping sonar that creates 3-D color-coded depth maps of reservoirs.

“We go up and down a lake taking sonar measurements of the lake’s depth,” Jakubauskas said. “In the past, a weighted line or a pole was used to take such depth measurements. It wasn’t very accurate and their location wasn’t very accurate. They might get 300 measurements in a single day. But with our sonar unit, we get between 100,000 and 500,000 measurements of the depth in a day.”

For more information, visit the ASTRA Web site or the Kansas Water Office site.