The notorious Vajont Dam is located in the territory of Erto and Casso. You can see it clearly from Longarone. Since 2007, the crown of the dam has been open to the public.
The dam and the Vajont tragedy
In the territory of Erto and Casso visitors can see the notorious Vajont Dam, which caused the October 9th, 1963, catastrophe taking the life of 1910 victims and sweeping away the town of Longarone. The Vajont disaster is one of the darkest chapters in Italian history: this long-shelved case was re-awakened also thanks to theatre show by artist Marco Paolini Il racconto del Vajont (the Vajont story) and film directed by Renzo Martinelli Vajont – la diga del disonore (Vajont: the Dam of Dishonour).
The dam was designed in the late 1920s to produce electricity from water: the project planned to exploit the deep gorge between Mounts Toc and Salta excavated by the Vajont stream, flowing from the Cellina Valley into the river Piave just in front of Longarone. The dam basin would serve to collect water from upstream dams and hydro-power plants built in the Cadore area along the course of the river Piave.
Construction works on the Vajont site terminated in 1960. One could even see the massive dam from down the town of Longarone: its 261 metre high double-arch structure and 360,000 cubic metres of concrete made it the highest of its kind in the whole world, the pride of Italian engineering. However, the major issue lied in the basin banks: the Mount Toc side bank was a massive pre-historical landslide consisting of 260 million cubic metres of heavy compact rock that hadn’t been moving for thousands of years but started moving again when the first filling tests started in the lake. Despite the warning signs nature itself was giving, the dam designers continued with their impoundment tests: their main worry was the protection of the investments they had made. In the months before the disaster, roaring, earthquakes and landfalls in the Vajont Valley intensified and up on the Mount Toc flank the M-shaped landslide profile appeared.
What happened on October 9th, 1963?
On the night of October 9th, 1963, people in Longarone were getting ready for bed. Somebody had stopped at the pub to watch the football match on one of the few televisions in town. Then, at 10.39 p.m. the massive landslide detached, fell into the lake and generated a 50 million cubic metre wave that split in two. One part touched the village of Casso and reached the lower houses of Erto, sweeping away the smallest hamlets on its way. The other part overtopped the dam, channelled into the Vajont gorge and plummeted into the Vajont Valley, crashing on Longarone.
The Vajont death toll was 1910 victims, most of whom were never recovered: in the Memorial Cemetery of Fortogna, not far from Longarone, each of them has their own white memorial stone as a tribute to their memory.