Kent bolsters levees to ward off floods
By STEVE HUNTER
Kent Reporter Courts, government reporter
November 11, 2009 · Updated 1:56 PM
“Everything is done on the east or north side of the river or on the right bank as you head down the river,” said Chad Bieren, a project manager for the city public works department. “That protects the majority of the valley.”
The 3-foot-square sandbags weigh nearly 3,500 pounds each. The bags increase the height of the Green River levees by up to 3 feet, meaning their capacity to hold back flood waters also is increased. As a result of the giant sand bags, the levees can handle river flows as fast as 13,900 cubic feet per second.
“This has been a very ambitious project,” said Tim LaPorte, city interim public works director. “The choreography is very difficult to achieve.”
Over the last two months, contractors have backed dump trucks down the Green River Trail to place the sandbags. The trail will remain closed to bicyclists as long as the sandbags are in place, but the trail will be open to pedestrians as a walkway.
The white sandbags are wrapped in black plastic to help prevent the bags from breaking down from exposure to ultraviolet rays.
The city hired two contractors to place the giant sandbags.
Fardig Development Inc. of Lake Tapps received $390,861 from the city to place sandbags along the river from LA Fitness at Highway 167 north to South 180th Street in Tukwila.
SCI Infrastructure of Pacific received $266,973 from the city to fill sandbags as well as place them along the river from the Horseshoe Bend levee on the south end of Kent to LA Fitness at Highway 167.
The city received $2.5 million from the King County Flood Control District and the Metropolitan King County Council to help pay for the sand, sandbags and contractors. The city also received $1.03 million from the U.S. Army Corps of Engineers to purchase the empty giant and small sand bags.
Fardig placed sandbags along the west side of the river between South 231st Street and South 200th Street to help protect the Riverview housing development and other housing areas west of the river, Bieren said. The company also placed bags along a 1,500-foot stretch of the river south of the city between Highway 167 and the Union Pacific railroad to protect auto yards and warehouses.
No sandbags were added to levees on the west or south side of the river, along farm fields or other open areas that would not see major damage.
Despite the raised levees, floodwaters could still strike Kent if the Army Corps releases water from behind the Howard Hanson Dam that increases the flow of the river to more than 13,900 cubic feet per second.
Initially, the U.S. Army Corps of Engineers, which operates the dam, indicated that there was a one-in-four chance that flooding could occur because of damage to one of the dam’s abutment.
However, temporary repairs to the leaky abutment have reduced the risk of flooding to one in 25.
The leak increases the risk of flooding this winter in the Green River Valley because the corps will not be able to store as much water as normal behind the dam. The dam is about 25 miles east of Kent.
Meanwhile, city crews through early November had given out more than 125,000 free, empty sandbags to residents who had filled up bags with more than 1,000 tons of sand at six sites.
WHERE TO TURN:
WEB SITE: www.choosekent.com
Kent CodeRED: Emergency Notification Systemshunter@kentreporter.com or 253-872-6600, ext. 5052.