By Kathy Brown, Groveland Yosemite Gateway Museum/Southern Tuolumne County Historical Society
What a winter we are having! Is the amount of rain and snowfall we've experienced so far unusual for California? How often do these long storms occur? How extreme have they been in the past?
Flooding and wind damage caused by winter storms is not rare in California. Over thousands of years the mountains and foothills have been scoured by the run-off of these winter deluges
running into rivers and creeks. The silt deposits they carried helped create the fertile soil in the Central Valley that allowed it to become rich grassland for grazing cattle, and to develop into the “breadbasket of the nation.”
California has always had years of drought and followed by a few wet winters. More recent
examinations of the soil deposits show that extreme storms and accompanying floods, now
called atmospheric rivers or ARkStorms, seem to happen approximately every 200 years or
less. Floods were a way of life in early Sacramento which was not very many feet above sea level. Excerpts from letters written by Dr. Jacob Stillman, who helped establish Sacramento's first hospital, describe what happened there in 1850.
“January 11th, 1850. - We are witnesses in another act in the great drama of Californian adventures. Perhaps, before this reaches you, you will be informed of the calamitous flood that is now spreading destruction and death through the valley. We are all, about forty of us, in the upper story of our hospital.
Jan. 12th - The water is still rising. Tents, houses, boxes, barrels, horses, mules and cattle are
sweeping by with the swollen torrent, that is now spread out in a vast sea farther than the eye
can reach. …the water rose at a rate of six inches an hour. What a night was that of 9th of January! A warm rain from the south melted the snow on the Sierra, and the river during the day rose rapidly, and about midnight began to overflow its banks.…Men continue to come begging to be taken in … they come in boats to the second story windows.”
This description could have easily been written a decade later when, after successive years of
drought in the late 1850s, one of the worst floods in history took place - “The Great Flood of
1862.” On Dec. 10, 1861, the Sacramento Union read, “Another calamity has overtaken our City
- a destructive Flood - it came with the rapidity of a hurricane - in a few hours the whole city was under water - the damage has been great - thousands are houseless while hundreds are in second stories in this city of 15,000 inhabitants many houses two stories high were swept and dashed to pieces …” This was the newspaper report in early December and the storms and their destruction continued until late January.
The excessive flooding described by Stillman was the result of more than a month of almost
constant winter rain and snow. This not only inundated the Central Valley, where some amount of flooding was not uncommon, but the ARkStorm was the largest and most destructive in Oregon, Nevada and California's more recent history. It caused flooding as far north as British Columbia and south to the Mexican border.
An unusual amount rain began to fall in Nov. 1861 with a heavy snow pack accumulating in the
Sierra. By December, the soils were saturated in the Central Valley and flooding began. A
“Pineapple Express” quickly melted the 10-15 feet of snow in the mountains. Also contributing
to flooding was the vast amount of debris from hydraulic mining done in areas such as our own which washed down-river and clogged waterways. Reservoirs and dams built to contain the torrents of water and prevent flooding did not yet exist.
The destruction grew. In just a few days an inland lake, 300 miles long, about 20 miles wide and up to 20 feet deep formed. Weeks later, on March 16, William H. Brewer wrote of Sacramento, “Not a road leading from the city is passable, business is at a dead standstill, everything looks forlorn and wretched.”
Records tell us that about 4,000 people died in this event at a time when California's population was about 400,000. The weather remained unstable throughout the spring. The flood waters did not fully recede until late summer so that recovery could take place.
But what happened in the foothill areas such as our own? Look for Part 2.
Taking You Back in History is provided by the Southern Tuolumne County Historical Society (STCHS) and the Groveland Gateway Museum. The Museum is open Friday - Sunday 10a - 2p