Emergenza Vajont: ecco come è stato risolto il problema del lago fuori controllo

Overcoming the challenge of water and securing the valley was a truly remarkable feat, requiring enormous efforts. Thanks to the study of some unpublished documents, this report will delve deeper into the historical phases of the post-disaster period, listing the main interventions carried out both in the rescue operations and in the works necessary to empty the lake. One of the most concerning aspects was the residual lake level upstream of the landslide, as the overpass tunnel had been found to be blocked, making it impossible to control the level of the reservoir. In this condition, without an outlet, the lake would have continued to rise, sooner or later submerging the village of Erto in the worst-case scenario. In the event of further landslides, the inevitable waves would have caused the water to overflow from the San Osvaldo pass, also putting the village of Cimolais at risk. A pumping system was therefore needed to control the lake level, but building such a facility with winter approaching, in an area often blanketed in snow, required enormous efforts. Therefore, a large number of companies were deployed. Among those who promptly responded to ENEL's invitation, some had already worked on the dam's construction, such as Torno of Milan, which will restore the road system, and Icos-Consonda, which will conduct surveys of the bypass tunnel. Already in the first weeks after the disaster, dozens of companies were operating in the area with all available resources. In mid-November, the construction of the pumping station was awarded to CESICA of Pordenone, while Monti of Auronzo began excavation work to lay the 1,800-meter wooden channel needed to convey the water beyond the S. Osvaldo pass. At the same time, the installation of new foundations for the reactivation of the 10 kV Gardona-Dogna line continues, and work has also begun on the two 20 kV Barcis-S.Osvaldo and Codissago-Erto-S.Osvaldo lines, which will supply power to the pumping station under construction. Meanwhile, the RAFFIN company of Pordenone has begun landscaping along the Tremenigia Valley for the drainage channel into the Cimoliana. ICOS-Consonda is preparing the construction site for waterproofing the S. Osvaldo pass. Meanwhile, the Pierobon company of Belluno began excavating the drainage tunnel on the Cimolais side on November 25th. At the same time, drilling of a 3-meter-diameter, 90-meter-deep well in the Tuora Valley is underway to intercept the existing tunnel on the Vajont side. Resuming partial excavation of the Cimoliana-Vajont tunnel is also being considered. These two incomplete tunnels were designed by SADE in the 1950s: one at 721 meters above sea level to divert water from the Cimoliana stream and use it in the Erto power plant, and the other at 640 meters above sea level to use water from the Vajont stream in the Cellino power plant. Both were never built. During the 1963 emergency, after appropriate modifications, these tunnels proved crucial in securing the lake. In February 1964, the pumping station became operational and remained in operation until August. Then, with the activation of the tunnel at 721 meters above sea level, the lake stabilized, but the reservoir was not fully secured until 1966, when the water level dropped significantly thanks to the activation of the tunnel at 640 meters above sea level and the flow through leaks in the bypass tunnel, which was finally cleared. For those wishing to learn more about the history of the Vajont Dam and the disaster, we recommend our two-part documentary, produced on the 60th anniversary of the tragedy, which provides a wealth of historical and technical information on the subject: [Great Vajont - Part 1]    • Vajont 60 anni dopo il disastro - Esploria...   [Great Vajont - Part 2]    • Vajont 60 anni dopo il disastro - Esploria...   [Inside the Vajont, the "secret" areas of the dam that no one has ever shown you]    • Dentro il Vajont 62 anni dopo, le zone "se...   https://www.loststructures.net/ Follow us on IG:   / channel   or on FB:   / loststructures     / 270073201116625   and also on Telegram: https://t.me/LostStructures You can help us too by supporting the LS channel with PayPal: https://www.paypal.com/ncp/payment/KY... Historical video credits: Archivioluce.com, Cineteca del Veneto, Ferrania Film Museum Historical photo credits: "The History of Vajont" (Edoardo Semenza), "Vajont the Dam" (Agostino Sacchet), "Vajont and the Other Dams" (Elsa and Rico Mazzucco) Gabriele Milani archive, Evaristo Fusar archive, Boris Brescak archive Music: Evan King - Titan Striker [CC-BY royalty-free music] #dam #hydraulic #hydro #engineering #disaster #abandoned #friuliveneziagiulia #explorer #exploration #loststructures #italian #history