A crack in a Columbia River dam is a concern for not only for the owner - the Grant County Public Utility District - but also for the Federal Energy Regulatory Commission and Bonneville Power Administration, which manage the Northwest power supply.
A crack in one of the 12 spillway piers at the Wanapum Dam was discovered last week.
Utility spokesman Tom Stredwick says the reservoir behind the dam is being drawn down 20 feet to help assess the situation.
Stredwick said Monday it's a serious situation but not an immediate threat of downstream flooding, even if that one section of the spillway were to fail. The 51-year-old dam is a mile long, spanning the Columbia about 5 miles downstream of where I-90 crosses the Columbia River at Vantage.