The St. Francis Dam Failure
In 1928 near what is today Magic Mountain , the worst civil engineering disaster in Untied States history occured.
Designed by the DWP Engineer William Mullhulland , the dam was designed as a storage facility in case of an earthquake on the San Andreas fault line . It was located in the San Francisquito Canyon near lake Elizabeth in the Leona Valley which was in and of it's self the San Andres.
if a dam such as this fails the results are simply beyond belief. Everything in the flood waves path is ripped to shreds. Only three people in the canyon actually survived the disaster and then only by luck. The canyon today has a ghostly feel to it. The death toll was set at seven hundred fifty but most likely was much higher being at the beginning of the great depression of the nineteen thirties hundred of homeless people were living in the Santa Clara River bed,
Even today at new housing projects , the remains of victims of the flood are found buried in the earth since nineteen twenty eight. Most victims were found with their clothes ripped off testifying to the intensity of the flood wave which was estimate at one hundred eight feet. The high water mark is still visible today in the canyon..
Such was the case in the St. Francis Failure/
The St. Francis Dam Was begun in 1924 and completed in 1926 . The Dam was 200 feet in height and 1200 feet across with the extension of a Wing Dyke. .
The St. Francis was one of if not the tallest Dam's in the World. The Gravity arch Design simple put means the dead weigh of the concrete is sufficient to support the dynamic load of the structure.
This is a very stable method of dam construction. The water pressure actually drives the side walls of the dam into the hillside giving it increased stability.
In the case of St. Francis , rock from the river bed was used in the dam construction as aggregate , and appearently was unstable and lead to the dams failure. Today rock from this are is illegal to use in construction.
Once again this type of dam rarely fails . However this design can be built to tremendous heights such as the Vionte dam in which failed catastrophically in 1963 near Venice killing almost 3000 .people in Italy . In this failure the Dam remained intact but the lake was splashed out by a landslide for near by Mount Toc in the Dolimite mountains. It went seven hundred feet above the dam and emergedas a three hundred foot wall of water destroying every thins downstream. This disaster is considered one of the worst in the history of Dams.. however in China in nineteen seventy five the failure of the Shimanton Dam and forty subsequent dams killed almost one million people . China has one of the worst safety records in history for dam failure but rarely reports them. Russia is a close second and has some of the highest dams in the world , some over one thousand feet in height.
there have been horrific failures in anticquity but the records have been lost.Egypt has had quite
few also having some of the earliest dam structures in the world.
On the morning of March twelve Mulhulland was called out to the dam by dam keeper tony Harsfenger Who reported severe leakage at the west abutment of St. Francis, with a muddy discharge issuing/ Any dam engineer at this point would evacuate down stream , cloudy water means that Hydraulic Uplift is occuring and the structure doomed to failure . It is just a matter of time , and how catastrophic...
Designed by the DWP Engineer William Mullhulland , the dam was designed as a storage facility in case of an earthquake on the San Andreas fault line . It was located in the San Francisquito Canyon near lake Elizabeth in the Leona Valley which was in and of it's self the San Andres.
if a dam such as this fails the results are simply beyond belief. Everything in the flood waves path is ripped to shreds. Only three people in the canyon actually survived the disaster and then only by luck. The canyon today has a ghostly feel to it. The death toll was set at seven hundred fifty but most likely was much higher being at the beginning of the great depression of the nineteen thirties hundred of homeless people were living in the Santa Clara River bed,
Even today at new housing projects , the remains of victims of the flood are found buried in the earth since nineteen twenty eight. Most victims were found with their clothes ripped off testifying to the intensity of the flood wave which was estimate at one hundred eight feet. The high water mark is still visible today in the canyon..
Such was the case in the St. Francis Failure/
The St. Francis Dam Was begun in 1924 and completed in 1926 . The Dam was 200 feet in height and 1200 feet across with the extension of a Wing Dyke. .
The St. Francis was one of if not the tallest Dam's in the World. The Gravity arch Design simple put means the dead weigh of the concrete is sufficient to support the dynamic load of the structure.
This is a very stable method of dam construction. The water pressure actually drives the side walls of the dam into the hillside giving it increased stability.
In the case of St. Francis , rock from the river bed was used in the dam construction as aggregate , and appearently was unstable and lead to the dams failure. Today rock from this are is illegal to use in construction.
Once again this type of dam rarely fails . However this design can be built to tremendous heights such as the Vionte dam in which failed catastrophically in 1963 near Venice killing almost 3000 .people in Italy . In this failure the Dam remained intact but the lake was splashed out by a landslide for near by Mount Toc in the Dolimite mountains. It went seven hundred feet above the dam and emergedas a three hundred foot wall of water destroying every thins downstream. This disaster is considered one of the worst in the history of Dams.. however in China in nineteen seventy five the failure of the Shimanton Dam and forty subsequent dams killed almost one million people . China has one of the worst safety records in history for dam failure but rarely reports them. Russia is a close second and has some of the highest dams in the world , some over one thousand feet in height.
there have been horrific failures in anticquity but the records have been lost.Egypt has had quite
few also having some of the earliest dam structures in the world.
On the morning of March twelve Mulhulland was called out to the dam by dam keeper tony Harsfenger Who reported severe leakage at the west abutment of St. Francis, with a muddy discharge issuing/ Any dam engineer at this point would evacuate down stream , cloudy water means that Hydraulic Uplift is occuring and the structure doomed to failure . It is just a matter of time , and how catastrophic...
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