In 271 BC the Roman consul Manius Curius Dentatus ordered the construction of a canal (the Curiano Trench) to divert the water from the marshes in the Rieti Valley and from Lake Velino over the natural cliff at Marmore, creating the waterfall. This caused flooding in the valley around Terni below. For a long time this became the cause of interminable quarrels between the cities of Rieti and Terni. The issue was so contentious between the two cities that the Roman Senate was forced to address it in 54 BC. Aulus Pompeius represented Terni, and Cicero represented Rieti. The Senate did nothing about the problem, and the problem remained the same for centuries.
In 271 BC the Roman consul Manius Curius Dentatus ordered the construction of a canal (the Curiano Trench) to divert the water from the marshes in the Rieti Valley and from Lake Velino over the natural cliff at Marmore, creating the waterfall. This caused flooding in the valley around Terni below. For a long time this became the cause of interminable quarrels between the cities of Rieti and Terni. The issue was so contentious between the two cities that the Roman Senate was forced to address it in 54 BC Aulus Pompeius represented Terni and Cicero represented Rieti. The Senate did nothing about the problem, and the problem remained the same for centuries.