Dry Falls, central Washington
The used card pictured above shows Dry Falls in central
Washington State as photographed by C. B. Ellis and published by the Ellis Post
Card Company of Arlington, Washington, mailed in 1991. During the last Ice Age water cascaded over
these walls, five times the width of Niagara Falls, in huge torrents making it larger
than any other known falls and thought to have been the greatest waterfall that
ever existed. Using models it has
been determined that the water would have been traveling 65 miles per hour
through the Upper Grand Coulee and over this 400 foot rock face. The estimated flow is ten times the current
flow of all the rivers in the world combined. Today Dry Falls is a 3.5 mile long “scalloped precipice” at
the head of the Lower Grand Coulee.
Glaciers moved south across North America nearly 20,000
years ago causing an ice sheet that made a natural dam flooding a significant
part of Montana forming a gigantic lake called Lake Missoula. During the same time period another ice
dam formed on the Columbia River making Glacial Lake Columbia. Eventually Lake Missoula rose so high
that the dam gave way causing a cataclysmic flood spilling into Glacial Lake
Columbia and then down the Grand Coulee.
It is thought that this flooding probably happened dozens of times
during the years of the last Ice Age.
The “sudden flood put parts of Idaho, Washington and Oregon under
hundreds of feet of water in just a few days.”
When the ice melted at the end of the Ice Age the river
returned to its normal levels and left Grand Coulee and these falls dry.
There is an Interpretive Center at Dry Falls in the Sun
Lakes-Dry Falls State Park located near the town of Coulee City. A Discover Pass is required for parking
but admission free.
Additional information can be found here:
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