Lake level to reach unheard-of lows as Ameren fights against high energy use

Joyce Miller
Frozen over Lake of the Ozarks.

High energy demands, upstream conditions at Truman Lake and downstream conditions on the Osage River, falling lake levels, and an ice jam on the Missouri River are all contributing to conditions on Lake of the Ozarks and Ameren’s operations at the Bagnell Dam Power Plant.

Lake of the Ozark’s water level dropped significantly this week as Ameren’s operations balanced the demand for energy with the annual winter drawdown and other conditions. On Thursday, the lake level dropped to 653.8 feet above sea level, a low seldom seen during the drawdown. By Sunday and into next week, Ameren anticipates dropping the lake as low as 652.5, an unheard-of low for Lake of the Ozarks.

A line of docks sits frozen in place as the Lake of the Ozarks froze over this past week due to bitterly cold temperatures.

Ameren’s guide curve for the winter drawdown is 654. Due to warmer winter temperatures leading up to the recent frigid blast, Ameren had held on to as much water as possible as a safety measure in case of bad weather and a need for an increased generation.

While lake levels around 654 in the winter are not unusual, the drop is usually more gradual than what happened over the last week when it dropped 4 feet.

More:Ameren Missouri continues to ask customers to conserve energy usage through Friday

Warren Witt, head of hydro operations for Ameren Missouri for the Osage Energy Center, said drawing the lake down is usually a slower process but with the energy demands, rolling blackouts and other conditions that the utility has to balance, it was unavoidable.

Starting in January every year, Ameren begins the annual winter drawdown of the lake to make room for spring rains.

Frozen-over Lake of the Ozarks through a line of trees.

Fluctuations in Lake and river levels occur for several reasons. Ameren Missouri generally lowers the water level at the lake during winter months to about 654 feet above sea level (or six feet below the full reservoir level of 660 feet) to reduce the possibility of flooding during spring rains. The Osage River level also fluctuates when Ameren Missouri's Bagnell Dam releases water during the drawdown.

Witt said the last week has been unprecedented. Ameren typically sees increased energy demands during peaks in winter and summer but as the arctic blast gripped the Plains region and beyond last week, Ameren and other providers were focused on trying to balance the power grid and keep supplies stable to avoid the rolling blackouts that some areas of the country experienced. Power loss during a period of time when temperatures were as low as what was experienced the last week poses a real threat to life.

More:Why is it so cold? How the polar vortex brings record low temperatures and winter storms

In addition to the lake, Ameren has to monitor levels at Truman Dam and downstream on the Osage River. Right now, Ameren and the U.S. Corps of Engineers are monitoring an ice jam on the Missouri River that could create a host of problems for industries along the river. With the Osage River flowing into the Missouri River, Ameren plays a role in water levels on that river, as well.

Early in the week, Ameren, which is part of the MISO, asked consumers to help reduce the stress on providers by conserving usage as much as possible. Witt said Ameren was not alone. Other providers serving consumers in the counties surrounding Lake of the Ozarks were also issuing usage alerts.

More:Camden County Road and Bridge struggling to keep up with dangerous conditions

When usage peaks, Witt said every degree difference on the thermostat, every light or appliance that isn’t used, helps conserve, allowing utilities to provide consistent power without having outages or having to cut power for periods of time. Witt said the investments Ameren has made over the last several years to upgrade their ability to provide reliable power, even during extreme weather events, paid dividends.  

Witt said Ameren is aware that the lake level is causing problems for property owners and there will be damage to docks but under the circumstances, providing power and maintaining water levels downstream have to be a priority.