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Early History Settlement Construction Era Aftermath Appendices

Daughter of Ice

The Columbia River began to flow into the Pacific Ocean straight through the Puget Sound about twenty million years ago. The Pacific and North American plates collided causing a volcanic uproar mixed with earthquakes to last the next ten million years. Mount St. Helens and the Cascade volcanoes are evidence of this catastrophic Hades-like age. Natural dams formed from lava blocked and rerouted the mighty Columbia over and again until finally the chaos subsided. Historian Marc Reisner called the Columbia "orphan of fire" (Reisner, 153).

coulee walls
The canyon walls of Grand Coulee bear the marks of volcanic basalt.

Reisner also called the mighty river "daughter of ice" (Reisner, 153). Just when the earth began to settle the ice age pounced on what is now known as the Pacific Northwest. Snow slid from the North Pole halting finally around the 47-30 parallel but sometimes continuing even further south. During these ice floods, an ice dam was formed in western Idaho. Geologist J. Harlen Bretz outlined this theory in the 1920s in Washington State naming the lake behind the dam, Glacial Lake Missoula. After having studied the previous 25 million years of volcanic activity that formed the state, Bretz attempted to explain the finer detailing of the landforms. Initially his theory was rejected from the science community but now this information is regarded as the closest working theory known as the Missoula Lake Flood. The glacier was pushed out of Canada damming the Clark Fork River, with a maximum elevation of 4,350 feet. The water behind it rose to a level of 2,000 feet deep in a pool stretching 500 cubic miles, "an area roughly the size of Lake Michigan and contain[ing] half as much water" (Reisner, 154). Eventually the ice dam, with a lesser density than the water, floated to the top, and released the harnessed water instantaneously. Historian Marc Reisner cites WSU geologist Larry Meinert who reports the volume of water as "a reasonable estimate is ten times the combined flow of all the rivers in the world" (Reisner, 154). The massive flood sought out the fastest route westward, which was the Columbia Riverbed. The monumental water flow of about "230 million cubic feet per second" (Reisner, 154) overpowered the channel and stripped the canyon walls carving deeper and wider with every wash. The water poured over plains as well, replacing large boulders across the river's side. The floods created the famous channeled scablands in the black basalt bedrock of the state. One channel outweighed the rest - "seven hundred feet deep, five miles across, more than fifty miles long" (Reisner, 154) - the Grand Coulee.

Grand Coulee
Grand Coulee

Coulee is a Canadian French word (origin 1807) meaning dry streambed. The Grand Coulee was so named in the 19th century to indicate the canyon once filled with water. Glacial Lake Columbia, in an act much like Glacial Lake Missoula, the Columbia River was overtaken at the point that the river turns northward, and the floods carved out a fifty mile long channel. When the glaciers melted the Columbia returned to its original course that diverts north at the Grand Coulee Dam, forms the border of the Colville Reservation heading westward to Bridgeport then south to Chelan. The flowing stream then abandoned the coulee and the remaining water evaporated. The Grand Coulee is now divided into the Upper and Lower Grand Coulee, the latter of which contains the site Dry Falls. Once the site of a magnificent waterfall as torrential floods crashed over its lips, Dry Falls is now a 400-foot deep footprint with glistening pools of water at the lowest points. Dry Falls Dam, a mile long earthen dam dividing the Upper and Lower Grand Coulee, keeps the former a reservoir and the latter dry. Before its existence the Grand Coulee was a fifty mile long canyon to sparkle only with water after one of very few rains. With walls as deep as seven hundred feet and at times five miles wide, early explorers found this space to be a natural wonderment on the way to more lucrative destinations, so the coulee remained untouched until America's dam-building era.
Dry Falls
Dry Falls

Other effects of the geological history influenced the recent use of the land. Fine silt known as loess was left behind in mounds by the glaciers the reallocated across the state by wind. Layers of loess created a land perfect for agriculture in an area of insufficient rainfall. The silt made a niche for a blond grass that remained until the white man arrived. This fine soil surrounded the Grand Coulee, which became through some derivative of manifest destiny, the site of a huge storage reservoir for irrigation farming. However, the benefits of this unique soil were short-lived. In other areas no loess covered the bedrock, exposing the black basalt. The topography when seen from the sky is mostly soft hills scarred by channels. When seen from far away, the earth appears rippled, as an imprint of the floods that formed it. Giant boulders are littered across the land, moved like marbles by the great floods.




Daughter of Ice Jeffersonian Imagination Native Understanding Lewis & Clark Journals Early Explorers Private Property

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