Slide

For at least 20 years, the risks of building on certain hillsides have been well known. But the risks haven't kept people from building homes on those that offer spectacular views.

So regulators who clear such sites for construction are getting more savvy about laying down rules that absolve local jurisdictions of liability and ensure that builders and buyers proceed with their eyes open.

Barring construction can invite lawsuits as well, so it is really not an option. But authorities do all they can to advise hillside dwellers that nature calls the shots when it comes to terra firma.

Slides spurred by winter storms have caused extensive damage in the Puget Sound area and killed four people on Bainbridge Island. In Seattle alone, 16 homes were left uninhabitable.

But in Seattle, virtually every sizable landslide occurred on a hillside the city had designated as a slide hazard. City regulators say they have little choice but to allow construction if slide experts show a home can be built safely.

New laws apparently are helping. Officials here and elsewhere say records indicate that most of the severely damaged properties were built before tougher environmental standards were imposed in the early 1990s.

On Capitol Hill, a New Year's Eve slide left a 10-foot chasm at Ed Weinstein's front door. But the Seattle architect's 6-year-old house stands virtually unscathed. Secured by deep pilings and steel-lined retaining walls, it essentially anchored the hillside.

In 1942, a slide on the same slope swept a home 750 feet down a ravine, killing a woman and gravely injuring her husband. But when the City Council pressed for a ban on steep-slope construction, city lawyers advised that the move would invite costly lawsuits.

Records show that Weinstein's house and nearly all the 22 other Seattle homes evacuated in December and January are on land classified as hazardous, the Seattle Post-Intelligencer reported.

Nearly all of the 100 or so sizable landslides that rumbled down Seattle hills this winter occurred within narrow zones designated as unstable because of landslide history, soil composition or steepness.

The challenge of handling risky development is "not a geological problem. It's a political problem," said David Montgomery, a geological sciences professor at the University of Washington professor. "We can identify fairly well areas that have a high propensity of failure."

The risks in Seattle were pinpointed a quarter-century ago. A University of Washington doctoral student used 30 years of landslide reports and weather records to produce a map identifying potential slide areas. By the early 1980s, those designations were reflected in land-use codes.

When Weinstein sought permission to build his home, the slide pattern was clear.

The city gave him the go-ahead in 1991, but Weinstein was required to sign a statement accepting "responsibility for the risk due to development in an area potentially susceptible to landslides." He also signed a waiver restricting his right to sue the city for landslide damage.

The house was pinned to the hillside with two dozen 16-inch-thick piles drilled into firm ground 24 feet to 36 feet below the surface. The hillside is anchored by a steel-reinforced retaining wall, buried 12 feet into the ground and rising six feet above. Storm runoff flows into an 18-foot holding tank, regulating drainage.

Although his house still stands, Weinstein can't move back in until workers erect an enormous retaining wall and replace his missing front yard. And the city has to repair a bridge that provides access to area homes.

Weinstein has filed a complaint holding the city responsible for ignoring warnings that its drainage system below was failing.

Margaret Pageler, a Seattle city councilor, won a 90-day moratorium on construction in slide-prone areas.

"The instability of our bluffs is a matter of record," Pageler said. "We all should know what the risks are. It's very important that people take on the risks themselves.

"That's what the moratorium lets us think about."