Valencia's relationship with flooding was ancient and well documented. Between 1321 and 1897, historians recorded up to 75 separate floods in the city, roughly one every eight years across seven centuries. The Turia, fed by storms sweeping off the Mediterranean, had a long habit of overwhelming its banks during autumn downpours. But familiarity did not mean preparedness. When heavy rains began in October 1957, they struck first in the inland towns of Chelva, Casinos, and Ademuz, causing light flooding. The rain continued building for days. By midday on October 14, torrential rainfall hit Valencia itself. The Natzaret district near the port was cut off from the rest of the city as water rushed through the streets. At least 81 people died, and the damage to property was staggering.

Ten days after the flood, on October 24, dictator Francisco Franco visited the devastated city. He promised government funding for reconstruction and supplies for those who had lost everything. In a regime that controlled the press and shaped public narratives, the flood presented both a crisis and an opportunity. Franco's government devised the Plan Sur, a scheme of extraordinary ambition: the Turia would be diverted entirely, rerouted through a new channel south of Valencia so that it could never again threaten the city center. The plan was not universally welcomed. The municipalities of Quart de Poblet and Mislata, located to the west of Valencia along the proposed new channel, objected to a project that would shift the flood risk onto their communities rather than eliminate it.

Despite the objections, construction on the Plan Sur began in 1964 and took nearly a decade to complete, finishing in 1973. The new course of the Turia ran 12 kilometers through a channel 175 meters wide, bypassing the city three kilometers to the south. The scale of the project was immense: an entire river, rerouted around a major European city. The old riverbed, suddenly dry and useless for its original purpose, presented an unexpected urban planning opportunity. Rather than filling it in and building over it, Valencia gradually transformed the former Turia into the Jardin del Turia, a nine-kilometer ribbon of parks, gardens, and recreational space that has become one of the city's most celebrated features.

The 1957 flood was catastrophic, but it did not end Valencia's vulnerability to extreme weather. Storm Gloria brought severe flooding to the region in January 2020. In October 2024, devastating floods again struck the Province of Valencia, a reminder that the Mediterranean climate's capacity for sudden, intense rainfall has not diminished. The phenomenon behind these events, known in Spanish as gota fria or cold drop, occurs when cold air from the north collides with warm, moisture-laden Mediterranean air, producing violent downpours concentrated over short periods. The Plan Sur protected the city center from the Turia, but the broader region remains exposed to a threat as old as the landscape itself.