Worse Than the Big One—California’s Looming Megaflood
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| Sacramento, January 1862, USGS |
Intense rainstorms began to pound central California on Christmas Eve, 1861, and continued nonstop for 43 days, converting the rivers that flow from the Sierra Nevada into torrents that flooded the Central Valley. Entire communities were swept away. Sacramento was under water for the next six months, forcing the state government to be relocated to San Francisco. The Central Valley became an inland sea that was 300 miles long and 20 miles wide. Thousands of people and hundreds of thousands of cows were killed. The state was