Water-filled barriers and walls constructed of concrete blocks could be used to hold back the Green River from the Maleng Regional Justice Center. But members of the Metropolitan King County Council were told this week that if the federal Howard Hanson Dam floods the Green River Valley, the justice center and other County facilities might still be unusable.

The news came in the second of a series of briefings held by the Council’s Committee of the Whole.

“While the county works with cities in the Green River Valley to coordinate mitigation efforts and emergency preparedness, we must also plan for the continuation of County services that impact all of King County,” said Councilmember Bob Ferguson, chair of the Council’s Committee of the Whole.

“King County provides critical services and programs that are located in the historic flood plain,” said Councilmember Julia Patterson, who also serves as Chair of the Flood Control District. “It is imperative that we take measures now to protect the County’s facilities and to keep operations running smoothly in the event of a flood.”

“King County’s job is to provide services to citizens. We need to keep these essential public facilities open and operating,” said Council Chair Dow Constantine. “We are actively planning to relocate services and provide as much road and Metro transit access as possible to the people of South King County who might be affected by flooding.”

The Council’s Committee of the Whole was briefed on plans now being made to minimize damage to County facilities in the historic flood plain while protecting the people who work in or are housed in the buildings.

To help keep water out of buildings like the Regional Justice Center, perimeter protection could be provided by walls constructed of concrete blocks and by plastic sleeves filled with water known as Aqua-Barriers, according to Kathy Brown, director of the King County Facilities Management Division. Even with those measures, she said staff will still have to pump out seepage around the walls and address groundwater that rises up inside the buildings.

Brown said the Department of Adult and Juvenile Detention is seeking agreements for locations to temporarily house both the jail inmates at the Justice Center and the courts and justice programs. She said inmates could possibly be housed in detention facilities in Kitsap, Pierce and Snohomish Counties as well as the Federal Detention Facility, while court operations might relocate to the King County Courthouse in Seattle or other owned or leased space.

“King County needs to take these proactive steps in order to prepare public facilities, county employees and the community for potential flooding,” said Councilmember Pete von Reichbauer. “The County’s ability to provide services in midst of an emergency is critical.”

“The aftermath of Hurricane Katrina taught us how devastating the damage – both human and economic – can be without proper planning,” said Councilmember Larry Gossett, chair of the Council’s Budget and Fiscal Management Committee. “King County is working with all of our partners as early as possible to ensure that the necessary steps are taken to protect the people in the valley and the businesses that are vital the economic health of the region.”‬

To prevent any disruption to the November general election, Brown told Councilmembers of a preliminary plan to move the Elections Office out of the Earlington Building in Renton to temporary facilities at the County’s Airport Operations Center by early October.

Brown said the focus at the King County Animal Shelter in Kent will be on the evacuation and housing of the shelter animals. She estimated housing will also be needed for up to 1,500 stray dogs and cats and 500 large animals and livestock, as well as animals that are found during the flood event, with temporary facilities for pets to be held nearby the emergency shelters where their owners take refuge.

Roads will be maintained for as long as possible before they are submerged by floodwaters, according to Harold Taniguchi, director of the King County Department of Transportation. He told committee members the department is working on “lifeline route” maps that would inform evacuees of the roads that are the safest to use. DOT is also preparing plans to reroute Metro Transit bus service to ensure that some form of public transportation would continue to be available as long as roads are passable.

Wastewater crews at the South Treatment Plant in Renton will stay on the job and keep the plant operating around the clock, even if they have to sleep at the site and be ferried in and out by airboat, said Jim Faccone, Safety and Health Supervisor with the County’s Wastewater Treatment Division. He said sleeping facilities will be set up and a week’s worth of food is already in place.

If needed, Faccone said wastewater could be shunted to the West Point Facility in Seattle to relieve pressure on the South Treatment Plant, which lies in what he called “the bottom of the valley” and treats wastewater for the Green River Valley as well as cities as far north as Mill Creek. He warned that if floodwaters shut down the facility, untreated sewage could flow into communities around the plant as well as Lake Washington.

“We’re taking every precaution to protect the lives of county residents, limit the damage to property, move facilities out of the flood zone, and ensure critical county functions continue to operate in case of flooding from the Howard Hanson dam, but the bottom line is that the federal government needs to step up and repair the dam as soon as possible,” said Councilmember Larry Phillips.

The U.S. Army Corps of Engineers discovered sinkholes and rapid seepage of water through an earthen abutment next to the Howard Hanson Dam after last January’s record rain. A temporary fix to inject grout into the earthen material to control seepage is underway but dam storage capacity will be limited until the repair can be tested next spring. A long-term fix could take three to five years.

Under a worst-case scenario, major County facilities downstream of the federal dam face the threat of flood waters as high as 10 feet. Heavy rains might make it necessary for the Army Corps to release much more water than they have in the past 47 years since the dam was built to avoid overloading the dam abutment.

Further briefings on the Howard Hanson flood threat will be heard in Committee of the Whole. The County is hosting a series of public meetings on the Howard Hanson flood threat, the first of which is on Wednesday, Sept. 9, at 6 p.m. at Green River Community College.

For more information go to: www.kingcounty.gov/safety/FloodPlan/Events.aspx.