NARRATOR: 1957.
70 miles from Venice,
amid the cliffs and gorges
of Italy's Vajont River Valley,
work begins on the Vajont
Hydroelectric Dam.
Crucial to the
dam's operation is
a vast reservoir that can hold
44 billion gallons of water.
Ever since the filling of
the reservoir in early 1960,
enormous cracks have begun
appearing on Mount Toc,
above the dam.
LUCIA FILIPPIN (IN
ITALIAN): People
could sense that something
big was about to happen
because the ground was
moving and suddenly,
new cracks would appear,
very deep and very large.
NARRATOR: Then, in late
1960, another warning sign.
This time, it's a landslide.
Though relatively small,
it prompts a flurry
of scientific research.
What it confirms is shocking.
As a direct result of
filling the reservoir,
Mount Toc has
become waterlogged,
dislodging a 720 million
ton chunk of rock that
is now slowly slipping down
the mountain towards the lake
below.
And so, in 1962, the
authorities lower
the water by over 70 feet.
At that level, they are
confident the dam can't
be overtopped, provided
the landslide falls
into the reservoir at
the speed they expect.
Even as locals grow
uneasy, officials
remain confident that
the threat is minimal.
FRANCESCO NICCOLINI
(IN ITALIAN):
No one had been
warned in Longarone.
There were no official warnings.
There were just the warnings
coming from the mountain.
NARRATOR: October 9, 1963.
Traveling at over 60 miles
an hour, three times faster
than expected, the mile and
a half wide chunk of rock
is finally unleashed.
In its sights-- the
enormous Vajont reservoir.
FRANCESCO NICCOLINI
(IN ITALIAN):
How can you imagine nine
billion cubic feet of rock
breaking away from a mountain
and falling into a basin
filled almost to the brim?
NARRATOR: It sends two giant
waves in opposite directions,
one towards the dam, the other
towards the village of Erto.
Traveling in over
30 miles an hour,
the first wave engulfs farms
and houses all along the shore,
killing most of their occupants.
Shielded by a spur in the
mouth, the village of Erto
is miraculously spared
the worst of the wave.
At the opposite end
of the reservoir,
the second tsunami
is now hurtling
towards the Vajont Dam.
It sends more than 275 million
tons of water over the edge
and into the valley below.
In its crosshairs, nearly
5,000 inhabitants of Longarone,
with nowhere to run.
The town is gone,
reduced to little
more than mud and rubble.
Of the town's 372 buildings,
just 22 are still standing.
The rest flattened and washed
away down the Piave River,
towards Venice.
ELISA DI BENEDETTO: Longarone
was not there anymore.
They could see that Longarone
didn't exist anymore.
There was only mud
and water and ruins.
No life at all.
NARRATOR: The violent disaster
claimed almost 2000 lives,
making it one of the worst
man-made disasters in history.
