SOUTH KING COUNTY - In his neighborhood in South King County between Kent and Auburn, Derold Cooter showed me just how high the last flood came in January 2006.
He figures that flood cost him about $2,500 in damage to his outbuildings and tools as the water rose in the land behind his house. His 5-foot-high fence was underwater. The good news is that the water never reached the house, which sits up on higher land.
Four years later, the worries for Derold Cooter and his wife Gloria are more pronounced because this time the flooding could be worse, a lot worse, because of problems with the Howard Hanson Dam. The risk of a major flood in the valley has dropped from an initial assessment of a one-in-three chance, down to on-in-33. That's because King County and the cities of Auburn, Kent, Renton and others have had a chance to prepare with sandbags and other measures. There's still a risk and, as the Army Corps of Engineers says, a permant fix to the leaking dam abutment is still years away.
"If we need to go through this for the next four or five winters, it's scary," said Gloria Cooter.
A temporary repair made last summer by pumping cement like grout into the leaking abutment is showing promise, according to the Army Corps.
So far, this winter's been mild, and the level of the Green River is still well below the tops of the levees, raised in many places by big bags of sand and special wire-framed walls filled with sand. There's still concern over the condition of some of the older levees along the Green.
But what happened to the Cooter's neighborhood along 94th Place South didn't involve levee failure in 2006, it involved something called a flap gate. The gate is connected to a pipe that goes through the levee and allows water from a nearby creek to drain into the Green River. But if the water in the Green rises, it automatically closes the valve to keep water from going back up the pipe, through the levee and flooding what should stay relatively dry.
The problem, says Cooter and King County's Department of Natural Resources and parks, is that debris kept that flapper from fully closing in 2006, providing a pathway for high pressure water to flood the backyards of Cooter and his neighbors.
Derold Cooter wants to see those gates monitored more closely.
"Monitor them at least monthly, if not weekly," said Cooter.
Doug Williams, a spokesman for King County DNR, says the flap gate was checked twice before this year's flood season, and will be checked again as flood crews are dispatched with the threat of high water.
"We go out and check that and many other flap gates," said Williams. "We have a lot of flap gates on a lot of levees on a lot of rivers in King County."
The Army Corps of Engineers now places the odds of major flooding in the valley at one-in-33. But despite work performed on the dam, the Corps says it will take several years to put a permanent fix in place, making the Howard Hanson Dam 100 percent secure.
To add a comment, please register or login.