Extreme weather.

It’s a term that gets tossed around these days like socks in a dryer.

Such has been the case in the past week of coverage of the two back-to-back atmospheric rivers plummeting California.

But how extreme is it?

Using the yardstick of the Great Flood of 1862 that set the recorded weather history benchmark for California extreme weather, it is a mere drop in the proverbial bucket,

Over the course of 43 days from November 1861 to January 1862, a non-stop series of atmospheric rivers dumped the equivalent of 10 feet of water in the form of snow and rain on California.

The 43 days of precipitation was then capped by a warm, intense storm in the Sierra that melted much of the massive snowpack.

That led to the well-documented flooding of the entire Sacramento Valley and San Joaquin Valley covering over 5,000 square miles with floodwater stretching 300 miles and in places to 20 miles wide to re-create what was once a great inland sea.

It was not — based on climatologists pouring over Army and private records — an El Niño event.

Such a monstrous El Niño style event has been used in hyperbole tucked into stories speculating if weather systems hitting California this year are of Biblical proportions or the storm of the century — or millennium — depending upon how dramatic the conjecture.

The 1862 event was the largest flood in the recorded history of California, Nevada, and Oregon. It also inundated large swaths of British Columbia and Mexico.

It rates as the worst natural disaster in state history, killing 4,000 Californians or the equivalent of roughly 1 percent of the Golden State’s population at the time.

The damage in 1861 when the state had 400,000 and not 39.51 million was estimated at $100 million. In terms of inflated 2023 dollars, that is equivalent to roughly $3.5 billion today.

The damage included one in eight homes being ruined or swept away in floods.

Some 25 percent of the state’s 800,000 head of cattle were killed.

Floodwaters full of sediment destroyed oyster beds.

In San Joaquin County, streets in Stockton were under between 3 feet and 6 feet of water for weeks.

Mokelumne City — a bustling town at a crossing on the river by the same name — was wiped out.

Manteca had yet to take root as a community per se.

But the recorded history of the county’s second attempt at a settlement after French Camp — a Mormon colony near present-day Caswell State Park south of Manteca and west of Ripon — gives an idea of what life was in a valley devoid of levees and dams.

Wet and stormy weather in the winter of 1846-47 caused the San Joaquin and Stanislaus rivers to overflow their banks.

At one point, the “river” opposite Corral Hollow near the base of the Coastal Range was three miles wide.

All of Sacramento was underwater which eventually led to  the existing townsite being rises by 10 feet.

Ironically, the rain at the outset was welcomed by farmers as California was trying to break free of a drought.

As such, it was the first recorded occurrence of the state’s well established cycle of drought punctured by a year — or years — of normal or above average precipitation.

Some climatologists believe based on hydrology history and carbon dating of tree rings, that events such as the Great Flood of 1862 occurs every 100 to 200 years.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com