The Annual Winter Draw Down of Water on Lake of the Ozarks
With Jeff Green of Ameren
Every year at Lake of the Ozarks, Ameren in coordination with the Corp of Engineers, carefully orchestrates a significant draw down of the water in the Lake of the Ozarks reservoir.
Preparing for Spring Rains
According to Jeff Green, Ameren Shoreline Management Supervisor, lowering the lake from 659 feet above seal level to 654 feet is to anticipate spring rains. Built for power production, the dam does not have excess capacity to control flooding often caused by spring rains.
Power storage and consumption as well as the benefits of lower lake levels for shoreline projects are not the factors driving the winter drawdown However, shoreline projects such as sea wall repair, rip rap and similar shoreline work is made easier for shoreline owners during the drawdown period. Jeff encourages lake front property owners to submit their Shoreline Stabilization Request to Ameren in the fall, to provide project review and approval time.
Daily Coordination with the Corp of Engineers
The lowering of the lake level and daily flows are carefully coordinated with the Corp of Engineers with consideration for Truman Lake, which provides flood control for the Osage basin, as well as, power generation. Considering that the Truman reservoir has significantly more capacity to hold back water from the Lake of the Ozarks, water flows have to be carefully managed. Monitoring flows through both Truman and Bagnell are of key consideration during the drawdown period.
Jeff confirmed that the drawdown typically begins in January with a gradual lowering of the lake to the target level of 654 feet by mid-February, 2017. Then beginning in April, they will begin to let the lake rise with the goal of having the Lake of the Ozarks back at full pool of 659 feet by Memorial Day weekend.
Risk and Concerns
When asked about the risk/concerns of this process, Jeff said, “the amount of precipitation is the biggest concern; if there is too little precipitation then it can be difficult to get the lake back to full pool. If there is too much precipitation it can cause flooding or difficulty in reaching full drawdown levels”. In addition to precipitation, Jeff stated, “we have other factors that can impact us, specifically inflow from Truman and required minimum flows into the Osage River that we have to maintain”.
In addition to the winter draw down of the lake level, winter on Lake of the Ozarks can bring lake ice, especially in the backs
of creeks that have shallow water and occasionally “lake-wide”. The lower of the water level, combined with current flow and ice can move and adversely impact docks and other shoreline facilities. Electrical safety is one of the biggest concerns of Ameren for dock owners. Jeff suggest that dock owners have their docks inspected throughout the year for electrical hazards and safety.
Impact on the Fish
Jeff, an avid Lake of the Ozarks fisherman, said “as the water level cools down and the lake level is drawndown, the fish seem to group up on some points and steeper creek channel banks near deeper water. Additionally flow can impact fish location even during the winter drawdown. During the periods when the dam is generating flow before water temps get too cold, he likes to target main lake and secondary points to catch the fish, as the bait fish may be more active in these areas. As the lake levels and temps begin to rise, the fish will begin to scatter and start moving closer to their spawning areas; I look for deep water and bank changes close to spawning areas in the early spring”.