AmerenUE Focuses on Automated Instruments in Breach of Reservoir Wall

DECEMBER 15, 2005 - Posted at 8:53 a.m. CST

LITTLE ROCK, AR - Owners of a hydroelectric plant in the rural Ozarks town of Lesterville will study why an automated system pumped too much water into a reservoir.

The pressure broke 600 feet of the retaining wall around the mountaintop reservoir before dawn yesterday, sending one billion gallons of water cascading down the slopes.  At least two homes were flattened and three children were critically injured.

St. Louis-based AmerenUE operates the Taum Sauk Lake Hydroelectric Plant.  The utility says it appears the plant's automated instruments pumped too much water into the 50-acre reservoir.  A set of backup instruments failed to detect the problem, and the company is trying to find out why.

The breach in the wall allowed the reservoir to empty in just 12 minutes.

(Copyright 2005 by The Associated Press.  All Rights Reserved.)