The Itinerate Mommy-- yes, I can read

Monday, October 15, 2018

What's a Grand Coulee and why is there a dam?

Wikipedia describes a coulee, "or coulée, as a term applied rather loosely to different landforms, all of which refer to a kind of valley or drainage zone. The word coulee comes from the Canadian French coulée, from the French word couler meaning "to flow".  The Grand Coulee is an ancient river bed in the state of Washington. We read about the guy (Bretz) who proposed the theory that these bizarre land forms were carved out, not from volcanoes, not from meteors, not from wind erosion, but from a massive flood, described as "Biblical proportions" from Missoula Montana-- many ice age floods as the result of ice dams forming massive lakes which would thaw, collapse and send floods again.  Above (Judd's panorama pic of Dry Falls) is where a waterfall many times bigger than Niagara Falls must have crashed. "This 3.5-mile-wide chasm of basalt, with a drop of 400 feet, was left high and dry thousands of years ago as the last of several Ice Age floods swept through the Grand Coulee. This is one of the most extraordinary landscapes to be found along the Ice Age Floods National Geologic Trail. "--also Wikipedia




Good Nova video for 2.45 minutes

or a longer read of the rebel geologists (and the 40 years of research before someone believed them):


Then there's the Dam.  What a cool visitor center!  We watched a 42 min old style newsreel-like movie of why and how the dam was built-- all black and white, all retro1933-1941.  You can watch it too: Grand Coulee Dam:  A man-made marvel

But you can't watch the last night of the laser show!  We dined in the town of Coulee and then walked back across the bridge over the Columbia River to the outdoor part of the Visitor Center.  The lights blinked a little cheesy story of the dam in pictures, with barely an homage to the indigenous people displaced by the building.
The dam is still run by the Bureau of Reclamation. The dam generates more than 21 billion kilowatt-hours of electricity for eleven western states.  And water is pumped over the hills to irrigate a large part of the county, known for producing more potatoes in one county then anywhere else in the US. The dam is one of the largest concrete structures in the world. After an airport-level security check the next morning, we were allowed to go on a tour inside the  power plant and up top the dam. My engineer-dude was happily impressed.

Grand Coulee Dam  Hoover Dam
550 feet height          726 feet
5,223 feet length       1,224 feet









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