Modern Marvels The Tennessee Valley Authority



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Bowmaster: "There was just so much to be done. But we didn't have to know the details. So we could fill in the details on the drawings later."

Footage of cement plant, trains, buckets, vibrator crews


NARRATOR: To support this building frenzy, huge concrete mixers were designed to churn out six tons of cement every minute. An ingenious railroad and cable system delivered this concrete in drop-bottom buckets. Crews with pneumatic vibrators shook air bubbles out of the cement as it settled.

buckets of cement empty out

VA's first dam, Norris, required 166-thousand buckets of cement--more than a million cubic yards, delivered around the clock, bucket by bucket, every 90 seconds.



still of partially completed dam, river flowing

When complete, Norris would be 265 feet high, and 1860 feet across. It could hold an entire year's rainfall, in a lake measuring 83 square-miles.



still man inside penstock, footage of penstock moving into place

Giant pipes, called penstocks, would funnel this water toward two electric generators. Each section of penstock weighed 40 tons, and moving them into place was treacherous business. Thousands of men risked their lives every day at TVA dams. The work was gritty, back-breaking, and above all, dangerous.










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