21. Val di Stava Dam Collapse, Italy
Built: 1969
Collapsed: 1985
Est. Damages: Unknown
One of the worst civil disasters in Italian history occurred on July 19, 1985, when two dams close to Tesero failed. It was determined that there was an issue with the dam’s drainage system, which resulted in an increase in pressure on the upper dam. The upper dam soon caved under the pressure and this led to the collapse of the lower dam as well.
Val di Stava Dam Collapse, Italy @David_Bressan / Twitter.com
The result was more than 6.3 million cubic feet of sand, water, and mud, rushing towards the village of Stave at speeds reaching up to 56 mph. Eight bridges and 63 buildings fell victim to the destruction caused by the dams’ collapse, and 268 people ended up losing their lives in the disaster.