The power of water is often underestimated, even more so when it is used in the generation of power and the potential energy that can be devastating if uncontrolled. This would be the story in a town in northern Italy when the effects of a landslide would cause a monumental flooding incident. I think this is the first time that we've covered an incident in Italy so salivated. Today's disaster is tragic as the loss of human life was so sudden and dramatic, but disaster at the Véont d'Am could have been avoided how the improper surveys and lack of proactive action led to a disaster over topping. Today I'm going to rate this subject here on my plainly difficult disaster scale. One of the tallest dams in the world sits disused at the foot of Montetoc, 60 miles north of Venice. The structure hoped to offer clean energy for the northern region of Italy, taking over 30 years from conception to construction, a time in which spanned a world war and several political changes in the country. When the construction was completed in 1960, a shocking disaster was not on the minds of the workers when they congratulated themselves on the monumental project just three years later. But how could an engineering marvel turn into a living nightmare? The first seed of a dam in the Véont gorge was traced back to 1920s. However, a couple of little known world events got in the way of the construction plans and work would begin in the 1950s after one of the little known events and a drastic government change of sorts was undertaken. SADE operated with monopoly in the region. Ground was broken in 1956 in the Véont torrent. We have worked being mostly completed by 1959 with inauguration in 1960. During construction works the project's license was extended to allow the dam to be raised by an additional 61 meters from the original plans, making it the world's tallest dam at the time. In Doom so, increasing the retention capacity to 169 million cubic meters instead of the 58 million cubic meters originally envisioned. The design of the dam made use of a double curve arch made a concrete 261 meters high with a width of 160 meters. Intended to provide as much electricity as possible, the structure impressively loomed over the village of Longoroni. Longoroni was a small town on the banks of the Pierre-Vie river. Its history goes all the way back to its establishment of a municipality in 1806, however the settlement's history goes all the way back to the Middle Ages. Geological studies have been undertaken in the area as early as 1928, with further studies in 1948 and more wearingly close to construction 1957. In August of 1957 a vulnerable zone was identified, hinting at the risk of a landslide along the banks of the soon-to-be-filled reservoir. Waringly in a nearby Montetoc was given the nickname the mountain that walks due to its known instability in the area. A local newspaper highlighted the local fears and legal action was taken against it for spreading false news and disturbing the peace. The basin began to be filled in early 1960 and within a couple of months small earth movements were recorded. A landslide was recorded in November when the reservoir was at a depth of 600 feet or 190 meters at an elevation of 645 meters, releasing around 800,000 cubic meters of material into the lake. The water level was decreased to a depth of about 450 feet or 600 meters of elevation. And more investigations into the stability of the banks were launched. Between 1961 and 1962, tests were conducted on a one two hundred scale model of the dam, results led to a maximum filling elevation of 700 meters being set for the dam. Once again the lake was filled in 1962 up to a limit of 700 meters of elevation and once again movement was recorded in the banks and local residents reported cracks appearing on homes. Again the water level was decreased stopping the seismic activity. During 1963 the dam was filled above its limit at 750 meters. And again the land around the dam and reservoir became unstable with land shakes and movements of up to 1.2 inches per day were recorded and this number was increasing daily. The dam's ownership changed from a privately owned monopoly to a government owned company named ENEL. The higher water level was exasperated by large levels of precipitation during the summer, which also fed into the banks' instability. Warried the operator decided to load a reservoir level again but this proved slow work. By September daily ground movements had increased to around 8.5 inches. A road that ran along the lake had deformed beyond use and by October disaster was never-table. With Monte Dox southside collapsing with movement at around 1 meter per day. On the night of October around 10.30pm the land slip began. Over 260 million cubic meters of earth and rocks slid down the mountain at speeds of near 90 kilometers an hour, creating a deafening roar as the material hurtled towards the lake. The water level at this point was at 700.4 meters of elevation just above what was thought to be a safe depth to prevent overflowing up the dam. The land slip cut off the electricity supplied to Longoroni plunging the doom town into darkness. As the massive material from the mountain entered the reservoir it displaced the water within creating deadly tidal waves. It was predicted the volume of the slide was about twice the volume of the water held behind the Vajant dam. A wave 150 meters high violently topped the dam flowing into the valley heading towards Longoroni. Powerful air streams first hit then the water and massive rock and mud flowed through the town decimating everything in its wake. Between 1900 and 2200 people were swept away by the uncontrollable flow. As seen here and used before and after photos the massive material had flattened Longoroni which was once a vibrant town was now a flat plane of mud. The dam itself was largely intact apart from a few outline buildings for electrical management and control. The main structure had only minor damage to the top of its masonry but destruction was inconceivable and the cleanup efforts would run into millions of man hours and even more in Lyra. Over 10,000 people were mobilised for the recovery and cleanup efforts led by the Italian army and many were volunteers. The works utilised hundreds of vehicles including bulldozers, helicopters trucks and other construction equipment to try and recover any survivors and bodies. Around 73 people were safe from the waters and rubble. Some 1600 round bodies were found with only around half of them eventually being identified. It is thought that around 350 families were entirely lost, leading to the many unidentified victims. On Sunday the 13th of October a mass ceremony was held for the endless line of coffins. The site was selected on farmland nearby. In hindsight the dam should never have been built where it was due to the large instability and unfortunately the alarm bells were newly ignored. Even at a fraction of the reservoir being filled instability was recorded but unfortunately like with many construction disasters once enough money has been spent on a project it has to be completed even against the evidence screaming the opposite. On 11th of October 1963 an investigation commission was appointed to determine the cause of the catastrophe and to find out who was responsible. This led to 1968 and on the 20th of February the assigned Belonno magistrate summoned 11 individuals to stand on trial on counts of negligent manslaughter due to the disaster being preventable. Three were died before sentencing with the remaining eight mostly being acquitted due to lack of evidence. However the lead engineer was sentenced in 1977 to five years of jail time although this was later reduced to one year. On 15th of February 1997 the Belonno civil and penal court sentenced to private company who originally built the dam to compensate the town of Longoroni for damages totaling 55 billion leera covering property non property and moral damages plus another 526 million leera for fees. Longoroni was rebuilt with a population today of around 4000. A panmy station was installed to keep the reservoir level low and a bypass tunnel was installed for water to flow around the dam. Although still in situ the dam is unused for its original purpose. The disaster highlights that it isn't always the dam itself that can fail but everything else around it and at the yont it seems that it was the right dam but in the wrong place. I hope you enjoyed the video. 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