Green Valley Dam could fail. Army Corps working hard to shore up dam above it.

This might sound a little confusing, but apparently the way to reduce the threat of the Green Valley Dam failing after heavy rains is to shore up the Howard Hanson Dam upstream. The article says this will reduce the chances of Green Valley failing to 1 in 25 this winter.

A failure would flood a heavily populated area just south of Seattle, WA.

Corps:  Dam work lessens Seattle-area flood chance. AP