Dams
Today, hydroelectric power. The University of Houston presents this series about the machines that make our civilization run, and the people whose ingenuity created them.
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Dams are fascinating structures. Beautiful, at least to my eyes. And wonderful sources of clean energy. But anytime we manipulate huge amounts of energy we must tread with caution. Coal-fired power plants damage our atmosphere. Nuclear power must be managed with care. Solar and wind power take up space.
And dams ... they sometimes fail. Not often. But some large collapses have had devastating effects. Some ten such failures have killed over a thousand people each. Only one after 1979.
Worst of these was China’s Banqiao Dam failure. Its death toll was hard to pin down. Maybe as few as twenty-six thousand. Maybe two-hundred-and forty thousand. This was during China’s Cultural Revolution. Information was hard to come by.
Each of those disasters failed to meet some challenge. So why’ve dams done better since then? Certainly greater care has to be part of the story. But let’s look at older dams still standing.
I have a favorite: Diablo Dam, built in 1930 – same year I was born. On the Skagit River, off in the Cascade mountains. It was the world’s tallest dam at the time – stood almost four hundred feet. And, when it began delivering power, it served a large part of Seattle’s power needs. It’s still active today. Of course its output is now a small part of Seattle’s far larger needs.
JHL’s first view of Diablo Dam in 1953
So let’s look at America’s largest hydroelectric power supply today. Most of it lies just east of the Cascade Mountains – in what we call the Columbia River Basin. Some hundred and sixty nine dams in that vast watershed. They supply around thirty-six gigawatts of power. Two of the earliest ones stand out: Bonneville dam and Grand Coulee Dam.
Bonneville Dam spillway
Bonneville was the first major dam on the River that had locks for boat travel. One of my job offers in 1951 was with Bonneville Power. And I later did research on the vibration of its power lines. It was a huge presence. And Grand Coulee dam, finished on its heels in North-Central Washington, is still America’s largest hydroelectric plant, even today.
Grand Coulee Dam - Song by Woody Guthrie
Bonneville Dam’s electrical switchyard above its powerhouse
I began by mentioning dam disasters. Let’s go back to that concern. Engineers of the Columbia River Basin certainly did something right. All those dams in its usual list, and not one has failed. Remedial work has been done, of course. But careful building and maintenance underlie this success. Dam building, like, say, nuclear power, can safely serve us.
So: while the Basin provides some forty percent of America’s hydroelectric power, that’s only around two percent of our total electric power. But it displays so much technical success. Now, may we just apply that same care to the other kinds of energy that we so voraciously consume.
I’m John Lienhard, at the University of Houston, where we’re interested in the way inventive minds work.
(Theme music)
Sources:
1975 Banqiao Dam failure - Wikipedia (Pronounced Bahn-chyow)
Cultural Revolution - Wikipedia
Diablo Dam - Wikipedia (Built by 1930. Delivered power in 1936)
List of dams in the Columbia River watershed - Wikipedia
My report written for Bonneville Power Admin. vortexcylinders.pdf
Account of a small dam failure and remedial work in its wake.
More information about dams here: Bureau of Reclamation
Grand Cooley Dam - Song by Woody Guthrie
Color photos by JHL and B&W one is his property
This Episode first aired on October 8, 2026.