The Great Flood of 1862

In the winter of 1861-1862, California experienced the most catastrophic flood in its recorded history. A series of atmospheric rivers — massive plumes of Pacific moisture — hammered the state for 43 consecutive days between December 1861 and January 1862. The result was biblical: the entire Sacramento Valley, 300 miles long and 20 miles wide, became an inland sea. In Yuba-Sutter, the Feather River rose nine feet above any previously recorded level. Marysville, situated at the confluence of the Yuba and Feather Rivers, was inundated. The young city's wooden buildings were swept from their foundations. Livestock drowned by the thousands. Fields that had been planted with wheat and barley disappeared beneath turbid brown water that would not fully recede for months. The human toll was staggering across the state — an estimated 4,000 people died, roughly one percent of California's population. Exact figures for Yuba-Sutter are uncertain, but contemporary newspaper accounts describe harrowing rescues and significant loss of life among settlers, miners, and particularly the Native and Chinese populations whose camps occupied the lowest-lying ground. Governor Leland Stanford had to be rowed to his inauguration in Sacramento on January 10, 1862. The state capital was temporarily relocated to San Francisco. Across the valley, entire towns were abandoned. The 1862 flood also had a geological dimension: decades of hydraulic mining had dumped millions of tons of sediment into the Yuba and Feather Rivers, raising their beds and reducing their capacity to carry floodwaters. The flood was nature's event, but human activity had made it dramatically worse. For Marysville and Yuba City, the flood was a turning point. The community began constructing levees — earthen embankments to hold back the rivers. These early levees were crude, built by farmers with mules and scrapers, but they established the pattern that would define the region for the next 160 years: a constant, uneasy negotiation between human settlement and the rivers that made it possible.