LAKE ROOSEVELT
The Grand Coulee Dam and the Columbia Basin Reclamation Project
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Section III.
THE COLUMBIA RIVER AND ITS WATERSHED (continued)
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In spite of the unprecedented use of machinery and power, men of a
great variety of crafts were employed, and much manual labor was
required in building the base of the dam. Final clearing of bedrock
was done by hand.
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The contours of the river bed were determined accurately by soundings
and cribs for the cross-river cofferdams were built to fit them. Riggers,
with their ropes and cables, were indispensable figures in the
construction crews
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Twin steel trestles, 3,000 feet long and averaging 95 and 175 feet in
height, were built across the canyon—and buried in the concrete
they carried. Over 75 million pounds of reinforcing steel will be required
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Four-yard batches of concrete, in huge steel buckets, were lowered into
the forms by long-arm cranes. After at least 3 days, each lift was
scrupulously cleaned with sandblast, air, and water before another was
laid on it
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Diagram of Grand Coulee Pump and Pumping Plant. (click on image
for a PDF version)
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grand_coulee_dam/sec3c.htm
Last Updated: 01-Feb-2008
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