🔗 Great California, Nevada, Oregon Flood of 1862

🔗 United States 🔗 California 🔗 Disaster management 🔗 Oregon 🔗 United States/Utah 🔗 Weather 🔗 Weather/Non-tropical storms 🔗 Weather/Floods

The Great Flood of 1862 was the largest flood in the recorded history of Oregon, Nevada, and California, occurring from December 1861 to January 1862. It was preceded by weeks of continuous rains and snows in the very high elevations that began in Oregon in November 1861 and continued into January 1862. This was followed by a record amount of rain from January 9–12, and contributed to a flood that extended from the Columbia River southward in western Oregon, and through California to San Diego, and extended as far inland as Idaho in the Washington Territory, Nevada and Utah in the Utah Territory, and Arizona in the western New Mexico Territory. The event dumped an equivalent of 10 feet (3.0 m) of water in California, in the form of rain and snow, over a period of 43 days. Immense snowfalls in the mountains of far western North America caused more flooding in Idaho, Arizona, New Mexico, as well as in Baja California and Sonora, Mexico the following spring and summer, as the snow melted.

The event was capped by a warm intense storm that melted the high snow load. The resulting snow-melt flooded valleys, inundated or swept away towns, mills, dams, flumes, houses, fences, and domestic animals, and ruined fields. It has been described as the worst disaster ever to strike California. The storms caused approximately $100 million (1861 USD) in damage, approximately equal to $3.117 billion (2021 USD). The governor, state legislature, and state employees were not paid for a year and a half. At least 4,000 people were estimated to have been killed in the floods in California, which was roughly 1% of the state population at the time.