Petaluma’s Past: A catastrophic engineering failure

It was the close of the “Roaring ’20s,” just three minutes to midnight on March 12, 1928, when an immense disaster hit southern California.

Our Petaluma Argus newspaper blared the headlines.

“200 Dead, 5 Towns Gone. Dead Strewn For 60 Miles. 500 Missing!”

The tragic collapse of the St. Francis Dam in the Santa Clara Valley, 40 miles north of Los Angeles, carried mud, boulders, bodies and debris for over five hours. It was a wall of water, traveling 54 miles, all the way to the ocean. The disaster claimed over 450 lives. Some victims’ corpses were found down the coast in Mexico, having been washed out to sea, their bodies badly mutilated from being swept against buildings, rocks and trees.

Only the Great San Francisco Earthquake of 1906 has cost more lives in a single U.S. disaster. Over 1,000 structures, bridges and roads were destroyed. The towns of Fillmore, Santa Paula, Bardsdale and Castaic were totally washed away. 24,000 acres of ranchland were gone. All across the Santa Clara Valley, only an hour’s drive from downtown L.A., it was said that the awful odor of death hung over valley for weeks.

How in the world had this public works tragedy evolved?

The rapid growth of Los Angeles had, of course, demanded an emergency water source, and respected local Engineer William Mulholland (think Mulholland Drive, et al) was appointed in 1925 to design a dam over the San Francisquito Canyon, near what is now Magic Mountain. The immense structure was 200 feet high and was designed to hold back 12 billion gallons of water, two years’ worth, for L.A.

Tragically, the St. Francis Dam became an example of how the fast evolving civil engineering of the ‘20s had begun to push the limits of technology. The massive dam had only just been completed that winter, and in the days preceding the disaster, the lake it was to hold back was allowed to fill for the first time. It finally came to its capacity on March 7, 1928.

The dam held for just five days.

The United Press on March 22, stated, “Witnesses tried to warn neighbors of risk, but not heeded. “ Dozens of theories were put forward as to the cause of the dam’s failure, and one was espionage. Ideas along those lines ranged from a plot by communists or Germans to disgruntled up-river ranchers. On March 20, the Argus reported, “The L.A. water board is sure dynamite was used. The evidence consisted of a chart of the dam and a piece of rope.”

Apparently, handwriting on the chart had been likened to one found in another dam’s dynamiting. A member of the L.A. water power board was quoted, “We don’t say it is proof of dynamiting. We only say it should be investigated further.”

Guards were immediately dispatched to the Los Angeles aqueduct, to ensure safety there.

Later, geologic researchers deduced that the dam had been founded upon, and had reactivated, massive “paleo mega-landslides.” Its foundation had not been built upon sound bedrock, but earth that couldn’t sustain the incredible weight and water placed upon it. Designers were totally unaware that the bed was geologically unstable, and thus could be activated to slide. Engineer Mulholland was later cleared of legal responsibility after much investigation, because that fault “couldn’t have been discovered by geologists, at that time.”

However, Mulholland’s career and reputation were ruined and he died a few years later, in disgrace.

Meanwhile, in the S.F. Bay Area then, controversy was raging over another engineering idea, the possibility of constructing a bridge from San Francisco to Oakland. In Washington, the U.S. Chief of Naval Operations opposed the idea, saying it would be, “Detrimental to naval defense and bottle-up the harbor.” San Francisco mayor James Rolf strongly objected to that testimony, telling the U.S. Senate, “In case of war, our fleet would not be bottled up in S.F. Harbor. It would be out to sea.”

He won out. We got our Bay Bridge.

1928 signaled the winding down of the “Roaring ‘20s,” and it wasn’t all bad news that year. In New York, the first-ever TV station was opened that December. In June, Amelia Earhart became the first female aviator to cross the Atlantic, the importance of something called “DNA” was established and, in Great Britain, the voting age-limit for women was lowered from 30 years to 21.

Oh. One other major event that year was the debut of a happy rodent named Mickey Mouse, in the Disney film “Steamboat Willie.”

Petaluma was still on top of the egg world that March, having shipped out 133 freight car loads of eggs the previous month. You could rent here a “Two Rm. Apartment. Bath. Sep. Entrance. Garage. $20/Mo. Phone 1453.”

Or, one could purchase, “A going dairy business. 84 ac. 4 miles to Petaluma. 6 rm. house, plenty water, outbuildings. 25 head cattle. 3 horses, all equipment. $15,000.”

And our Tomasini Hardware would sell you, for that ranch, a “De Leval Milker with pulsator located within inches of the udder, insuring instantaneous transmission of pulsations to teat-cups.”

(In case you’ve always wondered about those things).

For your auto driving pleasure, you could buy in Petaluma that year, a “New Marmon Straight Eight w/4 wheel brakes,” at J.H. Madison, at 12 E. Washington St.

And for having that snazzy feel in your new ride, ladies could purchase, at Goldman’s (107 Main St.), “Rayon Bloomers in pink, orchid or peach. $1.00.”

Other U.S. names of ‘28 were Sonja Heinie, Charles Lindbergh, Admiral Byrd, Glenn Miller, Eliot Ness and Margaret Mead. However, looming upon the world stage were other names - Stalin, Hirohito, Mussolini and Hitler.

The stock market crash, the Great Depression and WWII were just around the corner, to end those “Roaring ‘20s.“ They had been mostly good times, but tempered with tragedy and stress as well.

History, it seems, is always a mixed bag.

We must anticipate it.

(Historian Skip Sommer is an honorary life member of the Petaluma Historical Museum and Heritage Homes. You can reach him at skipsommer@hotmail.com)