December 14, 2005

Breach at Ameren plant unleashes flood in Missouri

CHICAGO (Reuters) - A ruptured reservoir that feeds an
Ameren Corp. hydroelectric plant unleashed 1.5 billion gallons
(6.8 billion liters) of water into the Black River in
Missouri's Ozark Mountains on Wednesday, the utility said.

There were no immediate reports of deaths or injuries
downstream from the 440-megawatt plant near Lesterville in
southeastern Missouri, but an Ameren spokeswoman said an
emergency plan calling for evacuations was activated.

Local media reported at least one family had to be rescued
and houses had been destroyed by a wall of water.

"From what we can tell at this point, the reservoir
appeared to have a rupture in the upper northwest corner that
caused the water to flow downward" and into the river, company
spokeswoman Erica Abbett said.

A lower reservoir -- which is nearly six times larger than
the 55-acre reservoir on top of Proffit Mountain that ruptured
-- is intact, she said. There was no effect on Ameren's power
output, as the plant is generally used only during peak demand

When the Taum Sauk Hydroelectric Plant is operating, water
from the upper reservoir is fed through tubes inside the
mountain to twin turbines. During low demand, the turbines are
reversed and water is pumped back up into the reservoir.

The plant was completed in 1963 and is operated by Ameren
subsidiary AmerenUE. Ameren serves 2.3 million customers in
Missouri and Illinois, the company said in a news release.