Our Big One A Seattle Fault earthquake could bring death and destruction far greater than anything ever seen in the Puget Sound region

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It’s a typical Friday morning in Kitsap County. It might be this Friday, or in a month or 10 years from now.

Steely gray clouds hover over the treetops, ferries glide across Puget Sound and traffic moseys along, slowed by the growing stream of commuters. Silverdale’s stores light up, the Navy Yard gates open and school bells ring.

Then it hits.

Walls shake, windows shatter, bridges fall, hillsides tremble and come tumbling down.

You think this is it — The Big One you’ve been hearing about. Warnings about a major earthquake rumbling up from the Cascadia Subduction Zone have been everywhere — magazine articles, reports on the evening news, even an entire book. Running along the Washington coast, the fault is ripe for a good shaking.

The expected magnitude-9.0 Cascadia earthquake would kick up town-devouring tsunamis on the coast and devastate cities across the Puget Sound region.

But the earthquake starting to roar to life on this hypothetical Friday morning is not the earthquake you’ve been hearing about. It’s much worse.

THE FAULT UNDERFOOT

The worst-case scenario for Kitsap is an earthquake grinding out of the fault right under our feet. Starting from Seattle’s eastern suburbs, the 43-mile-long Seattle Fault runs under Puget Sound and across south Bainbridge, East Bremerton and Central Kitsap before slipping under Hood Canal.

Seattle Fault The Seattle Fault, which runs through Kitsap County from Hood Canal to Puget Sound, is one of the region’s major fault zones. Scientists have evidence an earthquake of magnitude 7 or greater that occurred 1,100 years ago generated a tsunami in Puget Sound and resulted in a 22-foot uplift of the south tip of Bainbridge Island.

The last time the Seattle Fault shook with a magnitude greater than 7.0 was around A.D. 900. The good news is Seattle Fault quakes don’t happen often. The bad news is nobody knows when the next one will strike.

The fact that the last one was more than 1,000 years ago has some scientists and disaster management agencies worried we’re due for another 7-pointer. The University of Washington has been studying the potential impact for more than a decade, and the Federal Emergency Management Administration just completed a detailed risk assessment for Kitsap. Its focus: How well Kitsap will fair if a 7.2-magnitude Seattle Fault earthquake struck today.

Unlike a Cascadia quake, which would keep its devastating waves a safe distance from Puget Sound, the Seattle Fault’s tsunami would send towering waves straight at Kitsap’s shores.

Despite advancements in seismic technology, a Seattle Fault earthquake and tsunami would come with no warning.

It would bring death and destruction far greater than anything ever seen in the Puget Sound region. FEMA estimates that an earthquake with a magnitude of 7.0 or greater could kill 155 people in Kitsap County if it hit during the school and work day. Thousands more would suffer injuries that range from minor to life-threatening.

MINUTE 1

As the violent shaking begins, a sickening back-and-forth thrusting of the ground knocks people off their feet. Old buildings are the first to go. Their walls crumble, and their ceilings give way.

Seattle Fault Earthquake Building Loss FEMA examined local parcel data from Kitsap County and analyzed it along with the shake map and liquefaction data from the state Department of Natural Resources to determine building damage during a 7.2 magnitude earthquake on the Seattle Fault. The damage is expressed as loss ratio, dividing the dollar loss of each building by its value. Information from the military was not included, and building data from the Port Gamble S’Klallam Indian Reservation was not available.

Drivers struggle to maintain control as vehicles veer right and left before slowing down on pavement that has suddenly buckled.

A long rupture appears on the Seattle Fault, pushing land on the south side 20 feet higher than the north side.

The greatest devastation is concentrated along the fault. This jagged line happens to cross through or near Kitsap’s most populated areas — Bremerton, Port Orchard and Silverdale — but no area of Puget Sound escapes entirely.

Power lines fall, causing widespread outages. Water and sewer lines burst. Cellphone and other communication systems go black. The Agate Pass Bridge falls. Other bridges and overpasses might remain standing, but they’re so damaged that vehicles can’t cross. Ferry terminals in Bremerton, Port Orchard and Winslow are crippled by shaking and pounding waves.

The unstable soil under downtown Port Orchard turns to jelly, intensifying the shaking and bringing many shops and restaurants crashing down. The same phenomenon of ground liquefaction happens in Gorst, south Bainbridge, around Kitsap Lake and across East Bremerton.

MINUTE 2

The shifting earth snaps the tsunami to life. As dazed survivors step out of their damaged homes, they see the wave rising. Buildings and people along the shoreline are walloped by the massive rush of water. It crashes into walls, splashes over rooftops and floods many low-lying areas like Gorst, Port Orchard, Manchester and Bremerton’s shipyard.

The tsunami reaches its greatest height — 13 feet — on the north shore of Dyes Inlet, where many Silverdale businesses and parks are located.

The big wave crashes over, but Dyes and Sinclair inlets trap the wave’s energy, producing a powerful back-and-forth sloshing effect. Boats and docks, pilings and busted bits from waterfront homes are slammed back into the shore. The USS Turner Joy becomes a battering ram, taking out the Bremerton Marina and banging into the legs of the Manette Bridge.

Buildings and other structures high above the water are not safe either. The earthquake triggers thousands of landslides throughout the region with damage or destruction to homes located above and below slopes. Homes built on fill or sand spits fall apart or tip at an angle, as the ground below them liquefies from extended shaking.

Large landslides along the shores of Illahee, Brownsville, Seabeck and the west side of Bainbridge trigger several small tsunamis that roll into already bruised and battered shores.

Scattered fires are ignited by broken gas lines, arcing electrical lines and other causes. The flames spread to damaged and undamaged structures.

About half of the county’s fire stations are not up to current seismic code and suffer serious damage. Firetrucks and ambulances are trapped in garages, and several firefighters are injured or cannot access the gear they need.

The earthquake is a nightmare for the 40,000 students attending schools around the county. They have been drilled in earthquake response, and their teachers keep supplies on hand for emergencies, but only a small percentage of school buildings were built or retrofitted to current seismic codes, leaving the rest vulnerable to shaking.

MINUTE 10

Another 80,000 residents are at work around the county. In the aftermath of the earthquake, tens of thousands of people scramble to get home or locate loved ones, adding to the chaos.

Roads out of Bremerton are gridlocked, despite an effort by the Navy and city to coordinate the release of employees. About half of the highway system in Kitsap would be functional after the quake, according to the FEMA report.

The Agate Pass Bridge, which doesn’t meet current seismic standards, isn’t the only bridge to fall. By FEMA’s estimates, at least seven bridges or bypasses in Kitsap are bound to fail.

With most ferry terminals out of commission, thousands of Kitsap residents who work in the Seattle area cannot get home. Seattle’s Colman Dock is awaiting a multimillion dollar renovation, largely because it would probably suffer severe damage if rattled by a Seattle Fault earthquake.

AFTERMATH

News of the earthquake spreads quickly throughout the world. But local emergency services are overwhelmed, and outside help cannot mobilize quickly enough to join rescue efforts. Locating survivors buried in the rubble becomes a top priority, as medical personnel scramble to find injured people and try to move them to safety along broken roads.

Located in the Seattle Fault’s highest-risk zone, Kitsap’s two major hospitals — Harrison Medical Center and Naval Hospital Bremerton — are hit hard.

If still standing, Harrison enters mass casualty mode, clearing emergency departments to receive a flood of new patients. Injuries caused by a large Seattle Fault quake overwhelm the capacity for hospitals to treat victims. Harrison’s two campuses and the naval hospital have a combined 380 general hospital beds, many of which were occupied before the earthquake. FEMA predicts a Seattle Fault quake could injure 400 to 500 people badly enough to require hospitalization.

Many patients and medical providers are unable to reach hospitals, blocked by impassible roadways. Other health care groups in the county have to pitch in. Eight clinics in Kitsap have received training to help bolster the county’s medical response during a disaster.

With more than 100 fires burning at once and mass casualties all around, firefighters, police officers and medical personnel are unable to deal with a multitude of problems that normally would receive plenty of attention. Damage to water systems only adds to the danger of spreading fires.

As the immediate sense of disbelief fades, neighbors begin to help each other, while emergency responders and community leaders come to grips with shortages of food, water and shelter. Disrupted supply routes, broken water lines and damaged buildings create problems lasting for months. Many schools that would have been converted to emergency shelters were destroyed or are unsafe.

Much of the earthquake’s response will be focused on Seattle and the rest of the highly populated Interstate 5 corridor. Kitsap — a peninsula that would be an island if not for a stem of land near Belfair — will have fewer bridges and ferries connecting it to the rest of the region. It might be isolated for days, weeks or months.

For the many people displaced from their homes, getting conditions back to normal will take time. Damaged homes will need to be inspected. Damaged roads might result in long, congested detours. Children will need to be transferred from damaged schools, requiring double-shifting of classes at new locations.

Dealing with dead and injured friends and relatives will take a toll on many people. Ongoing aftershocks will rattle the nerves of most everyone, and some people will suffer post-disaster stress. Financial problems will be serious for many families affected by the earthquake, especially those without special earthquake insurance.

FEMA, in cooperation with the United States Geological Survey, has modeled the predicted shaking intensity for a 7.2 magnitude earthquake on the Seattle Fault. This shake map was used to estimate damage to buildings and infrastructure in Kitsap County during such a quake as well as the loss of life and injuries. Legend: Severe to violent Shaking

Severe to violent Shaking Very strong to severe shaking

Very strong to severe shaking Strong to very strong shaking

Strong to very strong shaking Moderate to strong shaking Sources: ESRI, HERE, DeLorme, U.S. Geological Survey, Intermap, increment P Corp., NRCAN.

This scenario of a Seattle Fault 7.2-magnitude earthquake was based on data and analysis done by the Federal Emergency Management Agency and the University of Washington Sea Grant. Ed Friedrich, Tad Sooter and Christopher Dunagan contributed to this report.

Gaps in Kitsap’s earthquake preparation

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Twenty years ago, scientists learned that a monster earthquake was lurking in the heart of Puget Sound.

A shallow rift, later named the Seattle Fault — running between Hood Canal and Issaquah — had the potential to drop hillsides into bays, move forests into lakes and throw tidal waves across nearly every stretch of shoreline. That’s exactly what happened about 1,100 years ago — the last time the fault roared to life. Scientists determined that the next big Seattle Fault quake and resulting tsunami could come anytime, but the next go-round would involve towns and cities, highways and bridges, and about 3 million terrified people.

To see what that might look like, scientists decided they needed a likely victim. Kitsap County fit the bill.

The county had small- and medium-sized ports, a variety of potential earthquake hazards, and an apparent interest in preparing for such a catastrophe — all of which was a good match for the team of government and university scientists searching for a place to test the first comprehensive Seattle Fault earthquake scenario.

Initiated in 2001 and led by the University of Washington’s Sea Grant program, the project included the work of scientists from the National Atmospheric and Oceanic Administration, the U.S. Geological Survey and the state Department of Natural Resources, as well as consultations with the Kitsap County Department of Emergency Management, Port of Bremerton, city of Port Orchard, Puget Sound Naval Shipyard and several other local governments, agencies and businesses.

The resulting 105-page report, titled “Reducing Earthquake-Tsunami Hazards in Pacific Northwest Ports and Harbors,” was released in 2005. In short, it found that a Seattle Fault earthquake with a magnitude greater than 7 would be nothing less than devastating. It predicted that the Bremerton shipyard would be a deathtrap of collapsing buildings. The ground would liquefy under downtown Port Orchard and Bainbridge Island’s Lynwood Center. Gorst would flood. Bridges would fall. Overpasses would collapse. Ships and waterborne debris would batter the shoreline. The floor of Sinclair Inlet might rise, snagging the bottoms of the few ferries still in operation. Fire stations would crumble, hampering the response to widespread fires, floods, landslides and a potentially overwhelming number of resulting injuries and deaths.

Local leaders responded to the report with a combination of disdain and indifference.

“Anything else you want to throw at us?” Kitsap County Department of Emergency Management’s director, Phyllis Mann, was quoted as saying after the tsunami risks were presented.

Before the report, the threat of a tsunami appeared limited to the coast.

“I guess we’ll just take it in stride,” Mann said in 2001. “It is one more hazard to worry about.”

But it wasn’t just one more hazard.

“There’s a great big basket of hazards that go along with this kind of earthquake,” the report’s lead author, Bob Goodwin, said recently. “Most people might see the need to prepare for landslides or wildfires and floods, and maybe lesser earthquakes like a Cascadia (Subduction Zone) earthquake. But by planning for a Seattle Fault earthquake and tsunami, you’re prepared for all of it.”

TRACKING PROGRESS

The report came with nearly 200 large- and small-scope recommendations for earthquake and tsunami preparedness. Specific agencies and groups were named to carry out the work.

The Kitsap County Department of Emergency Management (DEM) — the county’s lead disaster preparedness, response and recovery agency — was saddled with the biggest burden. Mann, now retired, remembers there was little in the report her small organization — which still has fewer than five full-time employees — could tackle. DEM and other organizations balked at the high costs associated with many of the recommendations, she said.

“We didn’t carry them all out, but I think we did a lot — if not most — of them,” she said.

But, of the two dozen recommendations citing DEM as the sole responsible agency, only about half have been met over the past decade, according to DEM’s current director, Mike Gordon.

The first big item checked off the list was moving CenCom, the county’s 911 service, out of a converted Warren Avenue Bridge toll booth and into a larger, custom-built facility in Bremerton’s West Hills. DEM moved there, too, abandoning an old house where countywide emergency communications were confined to a kitchen table.

Following the report’s recommendations, DEM has developed agreements to use schools and other facilities as shelters and temporary health care sites.

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DEM has carried out several recommendations aimed at improving public education. It has continued to bolster its emergency preparedness programs for neighborhoods, schools and businesses. It provides workshops on low-cost earthquake mitigation techniques and has established classes on structural retrofits that help buildings withstand earthquakes.

DEM does not, as the report recommended, maintain a roster of the county’s doctors, nurses and other emergency health care workers. The roster could prove especially useful after a tsunami because many of the county’s doctors and other highly paid medical professionals live on waterfront properties vulnerable to slides, flooding and large waves.

Gordon said DEM hasn’t invested in additional portable radio repeaters, which can improve communication when phone lines and cell services are down, according to the report.

“Those are spendy,” Gordon said.

DEM has an annual operating budget of about $600,000. The budget has increased only slightly over the years to keep up with rising employee health care costs and cost-of-living increases. New programs or large-scale spending plans are typically paid for with project-specific grants. Grant money isn’t as easy to come by now that one of DEM’s main funding sources — the U.S. Department of Homeland Security — has reduced spending for local agencies.

Several recommendations for DEM to develop a public tsunami warning program have gone unheeded.

“Signs cost money,” Gordon said in response to a recommendation that DEM design and install tsunami hazard and evacuation signs, much like the ones used in coastal areas.

He admitted tsunami signs could be particularly useful for tourists and new and temporary residents, such as members of the Navy. The warnings might make sense in marinas and in downtown Bremerton and Port Orchard, as the report recommends.

“It is probably something we could revisit, but I’m not sure how effective (tsunami warnings) are,” he said.

A recommendation to map alternative water routes between key locations in Kitsap hasn’t been realized, but Gordon said a program initiated on Bainbridge Island could serve a similar purpose if applied to the rest of Kitsap. Known as the “emergency flotilla,” the program would tap a network of island boat owners who would volunteer their vessels to transport food, supplies, emergency response personnel and other workers.

In some cases, the report’s recommendations were misdirected. As Gordon notes, the report’s recommendation that DEM enhance the county’s 911 capabilities should have been aimed at CenCom. DEM lacks the authority to carry out the recommended integration of local marine resources, such as Navy tug boats and commercial supply ships, into the county’s emergency management network. That, he said, would be better directed at the Coast Guard.

FIREFIGHTER PREPAREDNESS

The report took aim at the county’s fire departments, urging them to upgrade buildings, protect their vehicles and take a more active role in preparing communities for earthquake hazards.

A decade after the report, more than half of the staffed fire stations in Kitsap do not meet current seismic standards and could be at risk of collapse. Stations that meet current standards were either built during the past 15 years or were retrofitted for seismic safety.

North Kitsap Fire and Rescue has the most earthquake-ready buildings, with three of its four staffed stations meeting current standards. At the bottom is the Poulsbo Fire Department, which has no stations that meet current standards. The Bainbridge and Bremerton fire departments each have one station that meets standards and two that do not. Half of South Kitsap Fire and Rescue’s six staffed stations are earthquake ready.

Central Kitsap Fire and Rescue did not respond to repeated requests to discuss earthquake preparedness. It’s unknown how many of its buildings meet the current standards.

Building or improving stations for earthquake readiness is expensive and usually requires a voter-approved bond. In February, Bainbridge fire passed a $16 million bond to replace its south island station and its headquarters north of Winslow.

Understanding that few fire departments could afford to replace or upgrade all below-standard stations, the report’s authors recommended that all departments require that at least one emergency response vehicle remain outside at all times. The policy would ensure that several firetrucks in the county would avoid becoming trapped or damaged by collapsing stations.

Fire chiefs balked at the idea of keeping their expensive vehicles outdoors.

“This is the Pacific Northwest,” Bremerton Fire Chief Al Duke said. “You can cut the life of a vehicle by a quarter if you leave it outside.”

The four fire chiefs who responded to the Kitsap Sun’s queries about earthquake preparedness each noted that their agencies were compliant with most of the report’s eight recommendations for fire departments. The chiefs of the Central Kitsap and Poulsbo departments did not respond to several requests for comment.

Following the report’s recommendations, most Kitsap fire departments have established alternative response routes to cope with bridge and road damage. They’ve developed resource allocation plans, identified high-need facilities, such as schools and nursing homes, and enhanced volunteer dispatch systems. Most departments have followed through with recommendations to improve training courses for residents and businesses, although training opportunities at most departments are limited to fire extinguisher usage.

No departments have developed robust programs to educate the public about wildfire risks posed by residential landscaping, as was urged by the report. In some areas, like urbanized Bremerton, the risk is low. But the rural sections of the county could face fast-spreading wildfires if a large earthquake ruptures gas lines or propane tanks during the dry summer months. Keeping trees and other combustibles a safe distance from homes is one measure that could greatly reduce risk to many Kitsap homes, according to the report.

Also not undertaken was a recommended policy of requiring firefighters and emergency medical technicians to store emergency equipment in their homes or vehicles. While not required, maintaining personal emergency preparedness gear and supplies is strongly encouraged by every department.

South Kitsap Fire Chief Steven Wright said the county’s fire departments are going to be overwhelmed regardless of how well-prepared they are.

“It’s really, really imperative that citizens realize they’ll need to be self-sufficient in a big earthquake,” he said. “We have 72,000 citizens in South Kitsap, and I have 72 career firefighters. That’s one firefighter for every thousand of them. There’s nothing that will allow us to touch every home in the first days (after an earthquake). It’s not humanly possible.”

Fire departments will focus their attention on critical infrastructure and clearing routes to hospitals. They’ll race to the places where people are concentrated — schools, nursing homes, apartment buildings — before they’ll be able to tackle the needs of individuals and families. It could take days or weeks before first responders can handle all of the county’s emergencies.

Kitsap residents will be required to help themselves and their neighbors, the fire chiefs said.

“It’s difficult for us to say, ‘You know what? There isn’t going to be enough of us, and that there isn’t going to be enough resources,'” Bainbridge Fire Chief Hank Teran said. “We’re going to be upfront and say that we need (the public’s) assistance.”

When the ground convulses and the weight of Puget Sound is thrown at Kitsap’s towns and cities, the first emergency responder you’ll be able to count on likely will be yourself.

“One of the biggest things that needs to change is the thinking,” Teran said. “Your community is what’s going to be your biggest resource. What we need to do is educate them and enlist them.”





ANOTHER WARNING

If the 2005 report did little to spur the county’s leaders into action, perhaps a new one will do the trick.

This time it’s the feds that are issuing a warning to Kitsap.

The Federal Emergency Management Agency is nearing completion of a Seattle Fault earthquake risk assessment for the county. The bulk of the work already is done, including a comprehensive computer modeling process that has formulated a range of estimates, including casualty numbers and building losses.

FEMA recently completed similar assessments for Grays and Pacific counties. Both coastal counties will be devastated by a tsunami produced under an earthquake scenario.

“We realize Grays and Pacific counties have extreme risk because of the tsunami impact,” said Kelly Stone, a FEMA risk analyst who led the Kitsap assessment. “All they are concerned about in Grays and Pacific is recovery because they can’t mitigate. ”

Basically, there’s nothing that coastal towns like Long Beach and Hoquiam can do to avoid being swept off the map. Kitsap, on the other hand, has hope.

“Kitsap County is in a good situation,” she said.

That is, if Kitsap heeds FEMA’s warning.

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“The effects of a major earthquake in Kitsap County would be catastrophic,” the draft assessment says. “Hundreds of residents could be injured or killed and a multitude of others would be left homeless.”

Under current conditions, Kitsap will suffer an estimated 155 deaths and more than 2,300 injuries in a 7.2-magnitude Seattle Fault earthquake, according to the assessment.

Building damage will soar up to $3.6 billion. It’s a high number, but it’s only slice of the destruction. Other infrastructure, such as roads, bridges and overpasses, and various utilities like power lines and sewer pipes, were not included in the cost analysis.

“Therefore these estimated losses should be considered a minimum,” the assessment says.

Bremerton has the highest average building loss ratio. About 45 percent of building value in the city will be lost by a 7.2-magnitude Seattle Fault quake. A few buildings named in the assessment as likely losses are Bremerton High School, the downtown library and post office, and the Kitsap Way fire station.

Countywide, about 155 schools, 93 medical facilities and 19 fire stations are expected to suffer substantial damage.

The most intense shaking will occur between Silverdale and Southworth. This zone of “severe to violent” shaking happens to hold the county’s largest population concentrations, including Bremerton, Port Orchard and Winslow.

Bainbridge Island and Port Orchard would be particularly hard-hit. Both communities have a high percentage of buildings in areas where ground liquefaction is likely.

If a liquefying downtown weren’t enough, Port Orchard also will be a prime tsunami target. Seven-foot waves are predicted to crash into the city’s waterfront and the rest of Sinclair’s south shore. The south and north shores of Dyes Inlet, including the Silverdale waterfront, might be hit with even higher waves.

The Kitsap County Public Works building on Austin Avenue and Cedar Heights Junior High School on Lippert Drive were noted as two significant buildings that would be largely destroyed by an earthquake.

Bainbridge was highlighted in the assessment for high landslide risk. The island has 177 buildings in landslide zones that could suffer $55 million worth of damage.

Landslide risk also is high near Holly and Hood Point on Hood Canal and near Kingston.

FEMA hopes its assessment spurs action on the part of city and county leaders.

Starting this month, FEMA officials will begin presenting its findings first with city and county planners and engineers and then with elected officials.

“We’ll talk them through the report and help them focus mitigation actions,” Stone said.

Actions could range from making priority lists for building retrofits to development limits and buyout programs for properties in landslide areas.

“We don’t want to scare people, but we do want to bring awareness,” she said.