This is the St Francis Dam, outside Los Angeles. Or rather, what's left of it. More than 50
metres high, holding back 100,000 tonnes of water. Until it collapsed catastrophically
in 1928, twelve hours after its chief engineer had said that the cracks in it weren't anything
to be worried about.
The chief engineer in question was William Mulholland. He's one of the reasons that LA
is the size and scale it is: Mulholland Drive, home of the stars, is named after him, and
his career before the dam collapse was astonishing. He was in charge of projects that diverted
a river, and caused what became known as the California Water Wars, as locals tried to
dynamite and destroy the infrastructure that was pulling all the water away from their
farms. At the opening ceremony of the Los Angeles Aqueduct, close to here, as water
cascaded down towards the growing city, Mulholland declared to the mayor of Los Angeles: "there
it is, take it". And they did. Remember, Los Angeles was just one small city among many
in the valley at that point -- but its charter didn't allow it to provide surplus water to
anyone else, so the only way for other cities nearby to get access to this was to give up
their independence and become part of LA.
And that might have continued, perhaps Burbank, Pasadena, Anaheim, other cities that have
separate local government today might all be part of one enormous city... if it wasn't
for the St Francis Dam.
The leading theory for the collapse is that the foundations were unsound: on solid bedrock,
the dam would have been perfectly safe -- but it was built on permeable ground, so the weight
of water held behind the dam started to seep through and soften the ground under it. There
had always been a couple of cracks in the dam; that was normal for the time, concrete
can do that as it sets. But more had started to appear, leaks were starting to grow. Mulholland
and his assistant inspected the dam, and decided that it needed maintenance, but the situation
wasn't desperate.
Well, maintenance couldn't have helped: the dam was twelve hours away from collapse. But
evacuation of the areas below could have saved hundreds of lives. Just before midnight, it
gave way catastrophically.
And as the courts of inquiry delivered their verdicts, and as the last standing parts of
the dam were demolished and cleared to stop sightseers and people taking grisly souvenirs,
the cities that hadn't been eaten up by LA yet: Beverly Hills, Santa Monica, plenty of
others -- decided that Los Angeles couldn't be trusted with its water projects. They all
refused to join, and instead they formed what was called a "Water District" with LA -- they
took joint control of any projects like that in future. The dam collapse didn't just end
Mulholland's career: it ended the assimilation of other cities into LA. We might talk about
the urban sprawl, everything in the valley, as being Los Angeles, but it's not: it's separate
towns and separate goverements, and one of the reasons is this valley and the dam that
isn't there any more.
The incredible drone shots in this video came from these guys. Go check out their channels.
This is Ed from Media Giraffes.
You can see all the 4K footage from this shoot
and a few others besides on his channel.
And this is Alex from Drone Gear,
if you want drone reviews and giveaways,
go subscribe to his channel.
And there's a subscribe button round here somewhere for mine as well, so...
Thank you guys! That was amazing!
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