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Army Corps Reduces Green River Flood Risk

Liz Jones

The Army Corps of Engineers says that recent repairs at the Howard Hanson Dam have greatly reduced the flood risk in the Green River valley.


Previously, the Corps estimated a 1–in–3 chance that a flood would inundate the heavily developed valley south of Seattle. But now the odds are improved to just a 1–in–25 chance.

Mamie Brouwer is a manager with the Army Corps. She warns people in valley to remain vigilant with emergency plans, because the risk is still serious.

Brouwer: "It's dependent on the frequency of the storms, the intensity of those storms and the duration of those storms. Certainly if we get another Pineapple Express this year like we had in January 2009 we will most likely have to release water that will even top the temporary measures that have been installed."

That work includes putting a curtain of cement around a weakened part of the dam. It was damaged during last winter's heavy rains.

The Corps has worked around the clock since August to reinforce the structure, and create better pathways for floodwater drainage.

Residents, businesses and local governments from Tukwila to Auburn have been working feverishly to secure their property and the levees along the winding river.

I'm Liz Jones, KUOW News.

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