Officials with Osage County Emergency Management reported Wednesday that discharges from Bagnell Dam were being reduced in an effort to prevent erosion on the lower Osage River.
Bagnell Dam is transitioning from water discharges of 54,000 cubic feet per second (cfs) to 34,000 cfs as measured at St. Thomas. This transition will be performed over a four-day period at about 4,000 cfs drop each day.
Emergency management officials said studies have shown that a major component of erosion is a fast drop in a river level after an extend high water situation. The upper banks become saturated after weeks of high water, and if they quickly lose support of the water level, they can slough off. By making this transition in flow slowly, Bagnell will allow the banks to "drain out" as the water drops slowly, helping to reduce erosion.
As of Wednesday, Ameren Missouri, which operates Bagnell, reported they were discharging at more than 38,450 cfs. Upstream on the Osage at Truman Dam, operated by the U.S. Army Corps of Engineers, the discharges were at similar levels. The discharges from both dams are kept at similar marks to make sure there are no large fluctuations in the Osage between the two dams.
Additional weather resources:
Corps of Engineers Missouri River basin reports
Ameren's Truman and Bagnall Dam daily report
Missouri state highway road closings