Skip to main content
King County logo


King County Executive
Dow Constantine

Triplett proposes $40 million to shore up Green River levees and prepare county services for potential flood


King County Executive Kurt Triplett announced he is sending three pieces of legislation to the King County Council this week to increase protection of people and businesses, their property, and county facilities and services in the event of a flood in the Green River Valley. He will request approximately $40 million for 2009 flood preparation costs.


Governor Gregoire and Executive TriplettKing County Executive Kurt Triplett today announced he is sending three pieces of legislation to the King County Council this week to increase protection of people and businesses, their property, and county facilities and services in the event of a flood in the Green River Valley. He will request approximately $40 million for 2009 flood preparation costs.

The Executive today sent a motion to the King County Council seeking council affirmation and extension of the Proclamation of Emergency he signed on Thursday, September 10. The valley is at increased risk of flooding due to damage to the Howard Hanson Dam that is operated by the U.S. Army Corps of Engineers (USACE) 34 miles upstream of Auburn.

Later this week he will request $8.4 million to temporarily increase the height of Green River levees and for other items to increase flood fighting capabilities. Additionally, Triplett is requesting more than $32 million to plan and provide for continuity of regional services such as Superior Court, elections, animal control, wastewater treatment and public health. This amount will also help protect county facilities such as the Maleng Regional Justice Center, the South Wastewater Treatment Plant in Renton and the Black River Pump Station.

While making the announcement along a section of the Green River levee at Kent’s River Bend Golf Course, Triplett was joined by Governor Christine Gregoire, Army Corps Seattle District Manager Anthony Wright, King County Flood District Chair Julia Patterson, King County Council Chair Dow Constantine, Kent Mayor Suzette Cooke, Auburn Mayor Pete Lewis, Tukwila Mayor Jim Haggerton, Renton Mayor Denis Law and representatives of the state’s congressional delegation.Executive Triplett speaking at Green River Valley flood announcement

“Even in tough economic times we need to continue to do everything physically possible to protect the people and property of the valley after the warnings we have received from the Army Corps of Engineers,” said Triplett. “It is the right thing to do even if the worst case scenarios don’t happen. Too much is at stake.

“We are working with our congressional leaders, the Army Corps and FEMA to be reimbursed for this work because of the extraordinary circumstances,” Triplett said. The Army Corps has advised the county that there is a one in three chance of heavy rainfall that would exceed the damaged facility’s reduced capacity during the three to five years it will take for permanent repairs.

“This isn’t about being frightened—we are not trying to scare people. This is about summoning the common sense and courage of Washington,” said Governor Gregoire. “We know there could be trouble, and rather than wait for it, we’re going to meet it with a thoughtful and ready response.”

Triplett thanked the Governor for the state’s help in preparing for worst case scenarios after damage was discovered when water behind the dam rose six feet higher than ever before during record rainfall in January 2009. In addition to providing help from state agencies, the Governor sent a letter to the Seattle District Manager of the USACE, Col. Anthony Wright, asking for federal money for equipment and installation of temporary fixtures that would raise the height of existing levees several feet in places to increase protection during some scenarios being planned for. The $8.4 million Triplett is requesting would augment or replace the money the Governor requested if the request is denied.

The request would pay for temporary devices to increase the height of the levees, possibly add a temporary wall set back from the levees to handle water that overtops, increase flood patrols on levees during storms, buy pumps and other flood fighting equipment and fund debris management at bridges.

The Executive will transmit legislation requesting the $8.4 million to be paid from the $35 million collected annually from the Flood Control District’s countywide property tax.

Wastewater flood preparations would be paid for with existing sewer fund balance if the council grants it appropriation authority.

In addition to temporarily moving elections out of its Renton location to ensure the November 2009 election vote count is not interrupted by a flood, the county is proposing to build a flood-proof wall to protect the Maleng Regional Justice Center (MRJC), which could see flood waters as high as six feet in parts of the building. The county is developing plans for concentrating most criminal-related court and jail services in Seattle while concentrating misdemeanants at the MRJC in order to make potential evacuation easier. Jail space for evacuated inmates is being arranged for in Kitsap, Pierce and Snohomish counties.

Other flood preparations include moving the county’s radio shop that is used by the counties, many cities, police, fire and utilities. Staff will digitize some paper files and move others to higher floors in buildings at risk of being flooded. Animal Control will permanently relocate and the county is securing facilities for strays and pets and livestock of evacuees during a flood.

Extensive plans are underway to keep the Wastewater Treatment South Plant in Renton operating even though it could be surrounded by flood waters. Plans include keeping enough staff on site and leasing enough power generators to ensure the plant continues to operate even though the underground sewage pipelines will be inundated with flood waters. The plant treats an average 110 million gallons a day of sewage from south, east, and north King County as well as parts of south Snohomish County. It has a capacity for 340 million gallons a day during storms.

Triplett cautioned that even with the levee work that’s been done and is being proposed, the Green River’s aging levees were not designed for today’s standards nor were they designed to handle the volume, duration and frequency of flows projected during heavy rains while the dam is repaired. He said the time is too short to do all the work needed along the 40 miles of levees in the valley before the start of this winter’s storm season November 1st.

Flood Control District Chair Patterson said the District completed repairs to 9,300 linear feet of Green River levees at five high-priority points in 2008. In partnership with the Army Corps, it is currently completing repairs to 2,200 linear feet of levees in Kent and two low spots near Auburn. The District is preparing to replace 18,000 linear feet of levees at 14 sites along the Green River in 2010.

The USACE has advised King County and cities in the Green River Valley that the dam cannot operate at full capacity and to prepare for possible flooding if water into the Howard Hanson Dam exceeds 12,000 cubic feet per second. Flows in the river reached above that level 15 times between 1932 and 1962 when the dam started operating. Calculations estimate flows would have exceeded that level 17-20 times since 1962 without the dam.

It is estimated the Green River Valley generates almost $46 million of economic activity per day and a major flood could cause up to $3 billion in damages. Approximately 26,000 residents would have to be evacuated from the lower Valley and several hundred more who live in the unincorporated upper Green River Valley if a flood is anticipated.

Related information

King County Executive
Dow Constantine
Dow constantine portrait

Read the Executive's biography