Wanapum Dam, A massive crack in a major Columbia River dam poses enough of a risk of dam failure that Grant County authorities have activated an emergency-response plan. Officials said there is no threat to the public from the crack in the Wanapum Dam, which is just downstream from where Interstate 90 crosses the river.
But utility managers are lowering water levels a total of 20 feet because they fear the structure otherwise could endanger inspectors trying to get a better handle on how seriously the dam is damaged.
“At this point we already know there’s a serious problem,” said Thomas Stredwick, spokesman for the Grant County Public Utility District (PUD). “We want to make sure the spillway is stable enough that inspectors are safe when inspecting it.”
Earlier this week, an engineer noticed a slight irregular “bowing” above the spillway gates near where cars can drive across the dam.
When divers finally took a look under water they found a 2-inch-wide crack that stretched for 65 feet along the base of one of the dam’s spillway piers.