Last weekend my wife, son and I drove out of the city (in a rented car! Luxury!) to see a natural formation that’s unique in the world: The Channelled scablands of central Washington. Great name, huh? For those of you who don’t know about the scablands, Dry Falls and Lake Missoula, here’s a quick ‘n’ dirty explanation: Thirteen thousand years ago during the end of the last ice age, much of Montana was covered by a body of water we now call Lake Missoula. Ice dammed a river valley in Idaho, creating a body of fresh water larger than several of the Great Lakes.
You won’t be surprised to hear that eventually, the ice melted, the water broke through the dam, and the largest flood ever in the history of our planet was unleashed. Over the course of three days, a 300-ft-deep flood raced across Idaho, Washington and into Oregon as it raced to the sea. The effects of this flood are still most prevalent in the central Washington area near Grand Coulee. There was a Nova program that covered this: Mystery of the Megaflood, but it doesn’t appear to be one of the shows they offer for free online. Maybe you can borrow it from the library, like we did.
What this means is that, out in the desert of central WA, are the effects of floods of water writ large. You know the ripples you see in sand when waves flow over them? Well, look at the land formation above this small town:

Those gigantic humps are marks of the flood. Crazy, isn’t it?
More below the cut, including Dry Falls, an ice age waterfall ten times larger than Niagra Falls. Continue reading
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