The Oroville Dam crisis exemplifies bad risk assessment, fouled by an unsound determination of hazard probability and severity.
It seems likely that Governor Brown and others in government believed that California’s drought was permanent, that they did so on irrational grounds, and that they concluded the risk of dam problems was low because the probability of flood was low. By doing this they greatly increased the cost of managing the risk, and increased the likelihood of loss of lives.
In other words, Governor Brown and others indulged in a belief that they found ideologically satisfying at the expense of sound risk analysis and management. Predictions of permanent drought in California were entertained by Governor Brown, the New York Times (California Braces for Unending Drought), Wired magazine (Drought Probably Forever) and other outlets last year when El Niño conditions failed to fill reservoirs. Peter Gleick of the Pacific Institute explained to KQED why the last drought would be unlike all others.
One would have to have immense confidence in the improbability of a future floods to neglect ten-year old warnings of the need from dam repair by several agencies. Apparently, many had such confidence. It was doubly unwarranted, given that with or without anthropogenic warming, the standard bimodal precipitation regime of a desert should be expected. That is, on the theory that man-made climate change exists, we should expect big rain years; and on rejection of that theory we should expect big rain years. Eternal-drought predictions were perhaps politically handy for raising awareness or for vote pandering, but they didn’t serve risk management.
Letting ideology and beliefs interfere with measuring risk by assessing the likelihood of each severity range of each hazard isn’t new. A decade ago many believed certain defunct financial institutions to be too big to fail, long before that phrase was understood to mean too big for the government to allow to fail. No evidence supported this belief, and plenty of counter-evidence existed.
This isn’t even the first time our government has indulged in irrational beliefs about weather. In the late 1800’s, many Americans, apparently including President Lincoln, believed, without necessarily stating it explicitly, that populating the wild west would cause precipitation to increase. The government enticed settlers to move west with land grants. There was a shred of scientific basis: plowing raises dust into the air, increasing the seeding of clouds. Coincidentally, there was a dramatic greening of the west from 1850 to 1880; but it was due to weather, not the desired climate change.
When the rains suddenly stopped in 1880, homesteaders faced decades of normal drought. Looking back, one wonders how farmers, investors and politicians could so deeply indulge in an irrational belief that led to very poor risk analysis.
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Tom Hight is my name, an old bachelor I am,
You’ll find me out West in the country of fame,
You’ll find me out West on an elegant plain,
And starving to death on my government claim.
Hurrah for Greer County!
The land of the free,
The land of the bed-bug,
Grass-hopper and flea;
I’ll sing of its praises
And tell of its fame,
While starving to death
On my government claim.
Opening lyrics to a folk song by Daniel Kelley in the late 1800’s chronicling the pain of settling on a government land grant after the end of a multi-decade wet spell.