Sunday, March 15, 2020

1924 St. Francis Dam Failure

(NationalMonumentSatellite)

This dam was built between 1924 and 1926 as part of Los Angeles water supply. Just two years later it catastrophically failed because the soils in the abutments became saturated and gave way. I've seen figures for its height as both 185' and 205'.

(Update: I copied this link from JohnP's comment to make it "hot:"
https://web.mst.edu/~rogersda/st_francis_dam/reassessment_of_st_francis_dam_failure.pdf)

Joel Windmiller posted six photos with the comment:
March 13, 1928
The St. Francis Dam collapse sent a 100-foot high wall of water 54 miles to the ocean over 5 1/2 hours, sweeping away 1,200 houses, 10 bridges and killing 400 - 600 people. Bodies washed ashore as far south as San Diego.
Aaron F. Litt https://sites.google.com/.../st-francis-dam-disaster...
Lee Aldrich Mulholland had no engineering education and designed this dam himself. City utilities then were exempt from engineering reviews. This dam was built on unstable land and the height was raised twice during construction. This led to many laws being passed so this couldn't happen again.
Terry Taylor Lee Aldrich there was a much better dam site Long Valley William McCausland passed on because the land was owned by Fred Eaton who by that time was no longer on good terms with Mulholland.
Kirk J. Poole Mulholland had a large ego. It cost dearly on this 1928 morning. I've been back there and saw the large concrete chunks that still litter the landscape. I visited from 1989-1992.
Kirk J. Poole Well schooled on Mr. Mulholland's monumental failure, despite all the soil warnings they were given. They didn't have even the most rudimentary warning system (bell alarms, etc.) all the way to the ocean from the dam. Over 400 people died. Sad day for California.
AJ Grigg shared
Scott Nielsen It was 100 feet high at first when in the canyon, but once it moved out of the canyon, it was not that high. The first thing that would come was a wall of debris ( houses, tress, cars ). As it moved towards the ocean, it got bigger and bigger, and slower and slower. That's why it took over 5 hours to reach the ocean and it gave telephone operators and the police on motorcycles time to get out in front of it to warn people to get out.
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The St. Francis Dam was based on the design of the Hollywood Dam and it was nearly identical in size and shape. So this photo gives us an idea of what the dame looked like before it collapsed.
Los Angeles Relics posted
Hollywood Dam under construction on February 2, 1924. Source: LAPL



2 comments:

  1. A very interesting study of the dam's failure:

    https://web.mst.edu/~rogersda/st_francis_dam/reassessment_of_st_francis_dam_failure.pdf

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    Replies
    1. Thanks. I added it to the notes to make it "hot."

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