A very tragic scene is playing out in Washington state. Sadly, this even was entirely avoidable. However, as is so often the case, real estate values trump geology.

The NY Times article In Ocean of Mud, a Plea: Leave Me and Find My Wife has a good sidebar explaining in simple terms how landslides happen. Local officials have claimed that this disaster could not have been forseen, but that is B*** Sh**, to put it mildly. Down about the middle of the linked NYT article is an pre slide air photo ("Extent of the Mudslide"). Anyone with the least bit of geologic background would recognize the old scarp from a previous slide, and the active undercutting of the toe of the old slide by the river.

And in fact, the Seattle Times article Risk of slide ‘unforeseen’? Warnings go back decades points out that this slide had been recognized and well documented numerous times in the past. Unfortunately, as the geologist interviewed in the video points out, people are unwilling to listen to mere scientists. And, in many cases, real estate interests have blocked efforts at zoning around recognized hazards. In some cases, geologists, engineeers, and others have been threatened with law suites if by publisizing hazards they impact real estate values.

The Atlantic photo spread At Least 14 Dead in Washington State Mudslide shows a number of good views of the slide and the body recovery efforts. In particular check out photo #10 which shows a before and after view. As in the photo noted in the NYT article, it is trivial for the trained eye to recognize the old slide being undercut by the river.

Most unfortunate.

I got on a soap box and ranted for a few paragraphs. But no one wants to hear it, so I just deleted it and will let it be.

Most unfortunate.

Nothing is more inevitable than gravity. My condolences to everyone impacted by this disaster.

It is sad that people have died and homes have been destroyed in Washington.

It is also sad that people/governments decide to build homes in cities on the coast that are below sea level, along known and active earthquake fault lines, below active volcanoes, deep in tinder-dry forests, below a mud-slide hill that has already given way multiple times before, etc. You can't avoid all hazards, but you think you'd be able to avoid the obviously predictable ones.

Not many places left to live, then.

Blizzards, Heat Waves, Drought, Tornadoes, Forest and Range fires. Floods, Volcanoes, Avalanche, Earth Quake, Allergies, Tick fevers.Cholera, Valley Fever, Malaria, West Nile, Wildlife attacks, War, Riots, Distant Medical Facilities, Nuclear Disasters, Oil Spills, Blackouts and Brownouts, Drug Cartels and Gangs.

There seems to be something for everyone.

This event evokes memories of the 2005-06 La Conchita landslide, right next door to me, also with multiple fatalities. Digging a bit into history, it seems that in 1906,the Southern Pacific dug away an area to serve as a catchment basin for the persistent landslides that had been plaguing their right of way along the coast. In 1926, the first houses were built within the catchment area.

If you drive North on US101, look to your right as you pass La Conchita. Note the funny dirt piles.. They are the landslide. Take note of the steep cliffs all around - landslides of the future.

You can build to resist and survive the effects of earthquakes, tornadoes, and hurricanes, but things like massive landslide and tsunamis are a different ballgame.

How can you get a mortgage or homeowner's insurance in such a situation? Regardless of zoning or individual stubbornness, you'd think private lenders and insurers would try avoid massive loss situations.

Natural hazards like we were talking about in the origin post in this thread just don't move into an area unexpectedly. They are known about well in advance. Thus highly predictable. But human-made hazards (riots, gangs, etc.) can "move in" and turn a previously safe place into a dangerous one. This does not happen overnight though, you will see the area declining over time, and thus you could call these hazards "somewhat predictable".

True enough -nearly every place is subject to various hazards and vicissitudes. Know Your Local Hazard Profile!

Some are almost universal - wildfires come to mind. Others are more regional in scope - in SoCal, we are concerned with earthquakes, but not with hurricanes. In Florida, the opposite is true.