California super floods, lessons from the past

A 43-day storm that began in December 1861 put central and southern California underwater for up to six months, and it could happen again so goes the headline story from a 2013 Scientific American article. We knew sooner of later the Oroville Dam problem would be laid at the feet of Global Warming, if not George Bush. It turns out California has a long history of major drought followed by massive flooding. It is a great read and well worth the time. First the fake news warning:

Nonexistent Global Warming Crisis Blamed for Trouble at Oroville Dam “Oroville Is a Warning for California Dams, as Climate Change Adds Stress,” the New York Times reported.

“Broken California Dam Is a Sign of Emergencies to Come,” reads an article published in Scientific American, adding that “[c]limate change is leading to more extreme rainfalls that can overwhelm infrastructure.”

Actually,

California has a history of abruptly switching from drought conditions to torrential rain.

Brewer describes a great sheet of brown rippling water extending from the Coast Range to the Sierra Nevada. One-quarter of the state’s estimated 800,000 cattle drowned in the flood, marking the beginning of the end of the cattle-based ranchero society in California. One-third of the state’s property was destroyed, and one home in eight was destroyed completely or carried away by the floodwaters.

The Coming Megafloods, talks about what is responsible for most of the largest historical floods in many western states. The megaflood to strike the American West in recent history occurred during the winter of 1861-62. California bore the brunt of the damage. This disaster turned enormous regions of the state into inland seas for months, and took thousands of human lives. The costs were devastating: one quarter of California’s economy was destroyed, forcing the state into bankruptcy.

Today, the same regions that were submerged in 1861-62 are home to California’s fastest-growing cities. Although this flood is all but forgotten, important lessons from this catastrophe can be learned. Much of the insight can be gleaned from harrowing accounts in diary entries, letters and newspaper articles, as well as the book Up and Down California in 1860-1864, written by William Brewer, who surveyed the new state’s natural resources with state geologist Josiah Whitney.

In 1861, farmers and ranchers were praying for rain after two exceptionally dry decades. In December their prayers were answered with a vengeance, as a series of monstrous Pacific storms slammed—one after another—into the West coast of North America, from Mexico to Canada. The storms produced the most violent flooding residents had ever seen, before or since.

Story over at Scientific American