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by Tim Steury
photography by Robert Hubner
Palouse Falls
The trail down into the canyon below Palouse Falls is loose
talus, poison oak, stinging nettles, and rattlesnakes. But mostly,
it's steep, dropping quickly through a notch in the otherwise sheer
basalt walls of the canyon. Still, WSU geologist Gary Webster, at
70 the oldest in our party, is the first to the bottom. In fact,
he's already fishing before the next one of us arrives.
Webster is the picture of contentment, not only because of the
anticipated bass eyeing his fly. He is deep within his element.
Although we've dropped barely 400 feet in elevation from the
canyon's edge, we've descended 12 million years in time.
The Palouse River at this point is about 60 feet across. The far
bank is thick with willow. Above it is a shelf of prairie sage and
arrowleaf balsamroot.
Upstream is a cloud of mist from the falls. The falls itself is
still hidden around a bend, but the roar of the river falling 180
feet fills the canyon.
The falls has diminished somewhat from the earlier spring
runoff. But even then, when it channels the melting snow and rain
of the late-winter Palouse, the falls is an insignificant drip
compared with the cataclysmic flow that created it, a mere 15,000
years ago.
In order to comprehend that extraordinary force, first consider
the basalt.
Above the shelf of sage and balsamroot are the upper flows of
the Columbia River basalts, the dense, black volcanic rock that
underlies much of southeastern Washington. About 18 million years
ago, says Webster between casts, the earth cracked, and great flows
of lava erupted, spreading from vents in eastern Washington,
northeastern Oregon, and Idaho across what is now the Columbia
Plateau. (One of those vents is exposed below the dorms on the
south end of the Pullman campus of Washington State University and
can be traced all the way to Davenport.) A succession of seven
flows continued over the next many million years. Some of these
flows reached as far as the Pacific Ocean. In fact, the basalt
bluffs of the Oregon coast originated from vents near Lewiston,
Idaho. In some places, the basalt underlying the region is 5,000
feet thick.
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Continued
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Unnoticed, even unknown to
many, the Channeled Scablands is the latest manifestation of
the region's catastrophic history. But in many ways it is not
what it used to be.
Palouse Falls
 Gary Webster (right) and Washington State Magazine editor Tim Steury
recover from descending 12 million years from the rim of Palouse River
Canyon.
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