Landslide hazards are among us in Kitsap County

April 27--KINGSTON -- It was a view of Puget Sound that most people only dream about. Eagles soared above the trees; ferries plied through the water; and the Seattle skyline notched the horizon.

"I didn't need a TV," recalled Steve Lickar of Kingston. "I could just sit back and watch the scenery go by."

It was a view that Lickar and his wife, Joellen, enjoyed for three years, starting when they bought their home in 2008 and ending soon after the land began to move.

As cracks in the ground widened and new holes opened up around their house on Washington Boulevard in Kingston, Kitsap County officials "red-tagged" the house in 2011. That meant that nobody could live there until repairs could be made. The concern was that the house would collapse in a landslide, killing everyone inside.

It was not an empty concern. In the winter of 1997, a family of four perished in a landslide on the steep slope above Rolling Bay on Bainbridge Island. Dwight Herren, a 43-year-old high school teacher, his wife and two young children were buried in their daylight basement, as 2,000 cubic yards of mud rumbled down from the hillside, shattering the house and pushing debris down to the beach.

After the tragedy, the city of Bainbridge Island paid greater attention to hazardous slopes when people applied for building permits, said Lynn Nordby, city manager at the time. More geological assessments were required, he said. City officials did their best to ensure the safety of new homes.

Each time it rains heavily, landslides occur in Kitsap County and throughout the Puget Sound region. Small landslides may go unnoticed, but the big ones can change lives forever -- provided that people can get away in time.

UNSTABLE CONDITIONS EXIST

It is a challenge to convince Puget Sound residents that they face risks residing in steep canyons, angular hillsides and shoreline bluffs, according to federal, state and local officials. If not disturbed, killer landslides may occur on a geological time scale -- over hundreds or thousands of years -- depending on the location. But development, earthquakes and the increasing frequency of heavy storms accelerate the danger for people living on or below a steep slope.

The March 22 mudslide in the Stillaquamish Valley near Oso killed more than 40 people and left the community in ruins. Recovery, if one can call it that, will take months, if not years. As in every disaster, lessons will be learned.

Mike Gordon, director of the Kitsap County Department of Emergency Management, said this may be a good time to increase public awareness of hazardous slopes in Kitsap County.

"We may wait to get the reports about lessons learned," he said. "We will take those lessons and start looking at what we can do as we move into next year. Maybe we will send out tips for people who live along the coastline. Maybe we will hold a preparedness campaign and talk also about response and recovery."

The Oso mudslide was 600 feet in height -- higher than most potential landslides in Kitsap County -- but the soil conditions that triggered the slide are not that different, according to Jeff Coe, a geologist with the U.S. Geological Survey who has studied the geology of Kitsap County.

"The Puget Sound lowland has similar stratigraphy," Coe said, noting that deposits from ancient glacial movements created unstable conditions, especially where slopes were formed.

"Even at Oso, they had glacial stratigraphy there," he said. "Rivers in the Puget Sound lowland are cutting through that stratigraphy. That downcutting and back-and-forth movement of the river creates the valleys and leads to unstable conditions."

Coe and his colleagues at USGS studied LIDAR maps to identify recent and ancient landslides throughout Kitsap County. LIDAR, which stands for light detection and ranging, has an uncanny ability to strip the vegetation off the landscape and reveal the naked scars of glaciation. The USGS researchers visited most of the landslide sites they discovered.

In all, they found 231 landslides of significant size. In total, the landslides covered nearly 1 percent of the entire area of Kitsap County. About two-thirds of those landslides were found along saltwater shorelines, where the slopes are made unstable by erosion at the bottom of the bluffs. Most of the others were found in deep canyons with streams at the bottom.

The largest landslide -- or more likely a series of landslides -- was found at Crystal Springs on Bainbridge Island. From the top of the landslide to the runout at the bottom, the slide covered about 5.4 million square feet, or about the size of 94 football fields.

The second largest slide was at the mouth of Big Anderson Creek near Holly, where the affected area was 3.6 million square feet, or about the size of 62 football fields.

In comparison, the Oso landslide was about 10 million square feet, nearly twice the size of the largest landslide found in Kitsap County.

The thing to realize, said Coe, is that landslides tend to repeat themselves in the same location, even if the next one comes decades or even centuries later.

FALLING IN LOVE WITH A VIEW

After their Kingston home was red-tagged, Steve Lickar and his wife moved out. They hired experts to figure out what it would take to stabilize the slope and save the house. They hit a financial dead end.

Lickar figures it would cost $200,000 to shore up the hill, but first the house would need to be removed. It would cost another $150,000 to stabilize the sea wall below the house. Then they would have to rebuild the house, which they bought for $330,000. It would likely cost more to rebuild.

"We can't live in it. We can't sell it. We tried to give it back to the bank, but the bank doesn't want it. Insurance doesn't cover it."

Lickar said he stopped making payments on the house, wrecking his credit, and he told county officials that he can no longer be responsible for it. The county assessor dropped the value of the house to zero, eliminating any taxes on the structure. Lickar thinks the land should be devalued as well.

"We cant do anything with it," he said. "We can't even burn it down, because the bank doesn't understand that it has no value."

The house is twisting, as one part of the structure moves downhill and another part stands still. It may be too late to save it.

The house is somewhat isolated, and no other homes in the area are at immediate risk, Lickar said. If the road to his house fails in a landslide, it would block the way for about 20 other houses farther down on Washington, a dead-end street. If that happens, maybe the Federal Emergency Management Agency would step in, he said. Stabilizing the road might help to stabilize his property.

If he could start all over again, the story would end differently, he said.

"I would have put more into the geological reports," he said. "What I saw showed the slide area farther north. I knew there were some risks, but I didn't take it far enough."

Falling in love with the view was the ultimate downfall, he said. While slope issues nagged at the back of his mind, he and his wife were excited. They talked about living there a few years and moving on. Slope hazards were forgotten in the moment.

"I would say to people that if they are living in this kind of situation, spend the $2,000 or whatever it costs to understand what you have," he said. "It could save your life at 2 o'clock in the morning."

Jeff Rowe, assistant director of the county's Department of Community Development, said for people living on or near steep slopes, understanding the risk should be worthwhile.

"Personally, I want to know what my hazard and risk are to the fullest extent," he said. "Slopes are not something you monkey with."

For existing homes, directing water away from the slope is generally a good idea, Rowe said. Trees on and above a slope are normally a good thing, but there are situations where their removal can increase safety. Smaller plants with deep roots are generally a good idea.

"Look up and down on your property," Rowe advised. "Is there something that has been destabilized or changed, or does it just look awful steep? If in doubt, I don't think there is anything better than having a professional come out ... But I know some people would rather buy a flat-screen TV or a hot tub while their house is falling in around them."

CALLS FOR MORE SLOPE SCRUTINY

Geotechnical engineers don't seem to be intimidated by slopes. If someone has enough money, they stand ready to stop any hillside from crumbling, or so it seems.

As more land gets developed in Kitsap County, some people seem to be looking for cheap property on which to build a home, said Wes Johnson, a geotech with Norm Olson Engineers of Port Orchard.

"When it comes to putting a house on some properties, the foundation alone can cost more than the house," he said.

Every site is different, he noted, and engineers must account for the amount and type of soil on a slope, the angle of the soil layers, conditions at the base of the slope, the presence and type of vegetation and the location of any water.

Homes can be built at the bottom of somewhat unstable slopes, provided that an engineer accounts for potential soil movement. One solution is to build a concrete wall in a "V" shape to divert any mud flow, like the bow of a ship going through the water, Johnson said. But one must clearly understand where the mud flow will go next.

Another plan is to build the back wall of the house with thick, reinforced concrete and few windows for mud to flow into.

One three-lot development was recently approved by the county on Beach Drive east of Port Orchard. Being at the base of a steep hill, the county is requiring that each house be designed by an engineer aware of the slope hazards.

Under current building codes, local governments have mapped areas of "high geologic hazard" as well as areas of "moderate geologic hazard." High-hazard areas generally have slopes greater than 30 percent, while moderate-hazard areas generally are those between 15 and 30 percent. Unstable soils and the presence of springs and wetlands also play a role.

When building a house in a high-hazard zone, the code calls for staying well back from the edge of the slope. The standard setback is equal to the height of the slope plus one-third the height. For moderate-hazard zones, the normal distance is 40 feet.

If a property owner hires an engineer, he may be able to convince county officials that a smaller setback is adequate. The project may require stabilization or reducing water flow down the slope to obtain a reduced setback. The county employs two planners with geology backgrounds to review the geotech reports.

County officials also retain the right to demand an engineer's report on any slope or even increase the setbacks, if warranted.

Since the builder or developer hires an expert of his choice, some critics say the county does not go far enough to ensure a margin of safety.

"We call it rubber-stamping," said Jim Aho of the Illahee Community Club.

He cites the example of a housing project known as Timber's Edge, where the developer proposed building stormwater ponds at the edge of the steep canyon above Illahee Creek. The developer's engineer approved a design with lined concrete vaults that would not allow water to seep into the ground. The county accepted the design, according to Aho.

"We said, 'This is really dumb,' and we hired our own geotech," he said. "Our geotech said it was a bad design."

Confronted by dueling engineers, county officials then hired a third engineer, who sided with the Illahee community. The developer then changed the design, moving the stormwater ponds back from the slope.

"When a developer comes in with a signed document from a professional engineer, that relieves the county of responsibility," Aho said. "The county is very trustful, and most of the time, nobody complains. But if there is a problem, someone -- like the community of Illahee -- has to pony up the money for more studies."

One idea would be for the county to seek out an independent engineer for projects where conditions are particularly hazardous. Developers would pay for work, as they do now with environmental impacts statements. The report could spell out conditions to be avoided during development.

County Commissioner Rob Gelder said the idea is worth considering as the county goes through a new hazard-mapping process. Another idea would be for the county to hire its own expert to review the geotech report filed by the developer.

"We're not interested in additional layers for the sake of more work, but I have asked staff to chew on that and see what makes sense," Gelder said, adding that community safety is the prime concern.

County officials are preparing to approve a $43,000 contract to update the current hazardous sites map, which was compiled in the 1970s. Since then, several additional geological studies have been conducted, including LIDAR surveys. The new map will include considerations of erosion hazards, shallow and deep-seated landslides and earthquake hazards, such as potential ground motion and liquefaction. It will also include recently identified earthquake faults.

"This additional analysis should give us more clarity and detail," said Rowe of DCD. "Our job is public safety. We are hoping to identify areas where the land has moved before and we need to pay special attention."

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