Levees Beneath Threatened Washington Dam Called Weak

Half a dozen stretches of levee on the Green River in Washington, below the threatened Howard Hanson Dam, are porous and unstable, according to a Seattle Times report.

Those stretches, between Auburn and Tukmila, are considered a failure risk should authorities have to release any appreciable amount of water from the dam, the newspaper said.

The stretches are old and porous. Therefore, water could seep into them and through them, and loosen the earth until it gives way, the report said.

“In 50 years the water has never been that high,” the newspaper quotes Tom Bean, a King County floodplain engineer, as saying. “Nobody can say what will happen.”

Last week, the Insurance Journal reported that a new analysis said that if flooding occurs beneath the Howard Hanson Dam the property damage could run as high as $30 billion.