Imagine the Sacramento River 20 miles wide: It happened in 1862

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• Great Flood of 1862
  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
  39 KB (3,953 words) - 15:42, 13 October 2015

The entire Sacramento and San Joaquin valleys were inundated for an extent of 300 miles (480 km), averaging 20 miles (32 km) in breadth.^[17] John Carr wrote of his riverboat trip up the Sacramento River when it was at one of its highest stages of flood:

“

... I was a passenger on the old steamer "Gem", from Sacramento to Red Bluff. The only way the pilot could tell where the channel of the river was, was by the cottonwood trees on each side of the river. The boat had to stop several times and take men out of the tops of trees and off the roofs of houses. In our trip up the river we met property of every description floating down—dead horses and cattle, sheep, hogs, houses, haystacks, household furniture, and everything imaginable was on its way for the ocean. Arriving at Red Bluff, there was water everywhere as far as the eye could reach, and what few bridges there had been in the country were all swept away. I managed to get to Cottonwood, and had to lay over for a week before any of the streams between there and Hay Fork Valley were fordable.[7]