While we’re waiting to see if this year’s El Nino will
be a drought buster, a dud or a disaster, we may want to contemplate a series
of storms that once dumped 66 inches of rain on Los Angeles in one season and turned
vast portions of California into an inland sea.
According to experts, it could happen again.
Retelling the tale serves to underscore the point that
California is no stranger to weather extremes. Droughts are followed by
torrential rains. Torrential rains are followed by droughts. We should be
prepared for either. But too often we’re not.
The story of this megastorm is told by B. Lynn Ingram,
a professor in the Earth and Planetary Science Department at UC Berkeley.
It appeared in Scientific American.
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.
Sixty-six inches of rain fell in Los Angeles that
year, more than four times the normal annual amount, causing rivers to surge
over their banks, spreading muddy water for miles across the arid landscape.
Large brown
lakes formed on the normally dry plains between Los Angeles and the Pacific
Ocean, even covering vast areas of the Mojave Desert. In and around Anaheim, flooding of the Santa Ana River created an inland sea four feet deep,
stretching up to four miles from the river and lasting four weeks.
Residents in northern California, where most of the
state’s 500,000 people lived, were contending with devastation and suffering of
their own. In early December, the Sierra Nevada experienced a series of cold
arctic storms that dumped 10 to 15 feet of snow, and these were soon followed
by warm atmospheric rivers storms.
The series of warm storms swelled the rivers in the
Sierra Nevada range so that they became raging torrents, sweeping away entire
communities and mining settlements in the foothills—California’s famous “Gold
Country.”
A January 15,
1862, report from the Nelson
Point Correspondence described the scene: “On Friday last, we were
visited by the most destructive and devastating flood that has ever been the
lot of ‘white’ men to see in this part of the country. Feather River reached
the height of 9 feet more than was ever known by the ‘oldest inhabitant,’
carrying away bridges, camps, stores, saloon, restaurant, and much
real-estate.”
Drowning deaths occurred every day on the Feather,
Yuba and American rivers. In one tragic account, an entire settlement of
Chinese miners was drowned by floods on the Yuba River.
This enormous pulse of water from the rain flowed down
the slopes and across the landscape, overwhelming streams and rivers, creating
a huge inland sea in California’s enormous Central Valley—a region at least 300
miles long and 20 miles wide.
Water covered farmlands and towns, drowning people,
horses and cattle, and washing away houses, buildings, barns, fences and
bridges. The water reached depths up to 30 feet, completely submerging
telegraph poles that had just been installed between San Francisco and New
York, causing transportation and communications to completely break down over
much of the state for a month.
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.
Sacramento, 100 miles up the Sacramento River from San
Francisco, was (and still is) precariously located at the confluence of the
Sacramento and American rivers.
In 1861, the city was in many ways a hub: the young
state’s sparkling new capital, an important commercial and agricultural center,
and the terminus for stagecoaches, wagon trains, the pony express and
riverboats from San Francisco.
The levees
built to protect Sacramento from catastrophic floods crumbled under the force
of the rising waters of the American River. In early January the floodwaters
submerged the entire city under 10 feet of brown, debris-laden water.
California’s new Governor, Leland Stanford, was to be
inaugurated on January 10, but the floodwaters swept through Sacramento that
day, submerging the city. Citizens fled, yet the inauguration ceremony took
place at the capitol building anyway, despite the mounting catastrophe.
Stanford was forced to travel from his mansion to the
capital building by rowboat. Following the expedited ceremony, with floodwaters
rising at a rate of one foot per hour, Stanford rowed back to his mansion,
where he was forced to steer his boat to a second story window in order to
enter his home. Conditions did not improve in the following weeks.
California’s legislature, unable to function in the
submerged city, finally gave up and moved to San Francisco on January 22, to
wait out the floods. Sacramento remained underwater for months.
Dependent on property taxes, the State of
California went bankrupt. The governor, state legislature, and state employees
were not paid for a year and a half.
Ingram warns that the lessons of the 1861-62 floods
should provide the impetus for flood disaster planning efforts in a region
where housing developments and cities are spreading across many floodplains. A
critical element of living in a place like California is an awareness of these
natural disasters, which requires a deep understanding of the natural patterns
and frequencies of these events.
Today we have building codes for earthquake safety, she
writes, but millions of new westerners are not aware of the region’s calamitous
climate history. Most have never even heard of the 1861–62 floods, and those
may not have been the worst that nature can regularly dish out to the region.
Ingram and her colleagues believe similar if not
larger floods have occurred every one to two centuries over the past two millennia
in California.
If they are right, we had better prepare for another
Big One.
Robert Rector is a veteran of 50 years in
print journalism. He has worked at the San Francisco Examiner, Los Angeles
Herald Examiner, Valley News, Los Angeles Times and Pasadena Star-News. His
columns can be found at Robert-Rector@Blogspot.Com.
Follow him on Twitter at @robertrector 1.
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