Vajont Dam Disaster – 60 Years Later

Today marks the 60th anniversary of the Vajont Dam disaster – a tragic event that serves as a stark reminder of the profound interplay between geology, engineering, and the forces of nature.

On the fateful night of October 9, 1963, a massive landslide plunged into the reservoir behind the Vajont Dam in northern Italy. The displacement of water caused a wave to overtop the dam, resulting in the catastrophic loss of nearly 2,000 lives in the towns below. While the dam itself remained structurally intact, the tragedy lay in the devastating force of the displaced water and the failure to fully understand and predict the geological complexities of the region.

Several factors contributed to the disaster. The Monte Toc slope, which collapsed into the reservoir, was known to have experienced landslides in the past. As the reservoir was filled, the rising water levels increased the hydrostatic pressure on the mountain, likely reactivating existing shear surfaces. Furthermore, deep-seated gravitational slope deformations and the geology of the slide surface, with its alternating layers of limestone, clay, and marl, complicated the mechanics of the landslide.

The town of Longarone, Italy after the 1963 Vajont Dam disaster

For us, the Vajont Dam disaster is not just a tragic event in history but a lesson that underscores the need for interdisciplinary collaboration. It highlights the importance of understanding the ground we build on, the need for continuous monitoring, and the value of heeding warning signs.

As we remember the lives lost 60 years ago, let us also commit to approaching our work with humility, rigor, and an unwavering commitment to safety.

Brief Documentary on the Vajont Dam Disaster

This documentary is not bad, despite the cheesy “Fascinating Horror” label. If you have HBO Max, I also recommend you check out the show “Mysteries of the Abandoned”, Season 2, Episode 1 (near the middle) which has a very good summary of the event with some stunning visuals and simulations.

Longarone, Italy – Before and After Photo

A Selection of Technical Papers on the Vajont Dam Disaster

This is by no means a comprehensive list, but if you are interested in learning more about the geotechnical aspects of the Vajont Dam landslide and subsequent tsunami, these are some good publications to get started with.

Hendron, A. J., & Patton, F. D. (1985). The Vajont Slide, a Geotechnical Analysis Based on New Geologic Observations of the Failure Surface. Engineering Geology, 24(1-4), 475-491.

  • This paper provides a comprehensive geotechnical analysis of the Vajont landslide based on new geologic observations. It’s often cited for its detailed study of the slide mechanics.

Genevois, R., & Ghirotti, M. (2005). The 1963 Vaiont Landslide. Giornale di Geologia Applicata, 1(1), 41-52.

  • This paper provides an overview of the Vajont landslide, discussing the geology, geomorphology, and the main factors leading to the landslide.

Kilburn, C. R. J., & Petley, D. N. (2005). Forecasting giant, catastrophic slope collapse: lessons from Vajont, Northern Italy. Geomorphology, 66(1-4), 69-84.

  • The authors discuss the challenges of predicting giant catastrophic landslides and draw lessons from the Vajont disaster.

Paronuzzi, P., & Bolla, A. (2012). The ancient Vajont rockslide: An updated geological model. Geomorphology, 139-140, 79-95.

  • This paper provides an updated geological model of the Vajont rockslide based on new findings and research.

Paronuzzi, P., & Bolla, A. (2012). Influence of the deep-seated gravitational slope deformations (DSGSD) on the Vajont rockslide (October 9, 1963, Italy). Geomorphology, 171-172, 224-235.

  • The authors explore the role of deep-seated gravitational slope deformations (DSGSD) on the Vajont rockslide, providing insights into the mechanics of the slide.

Semenza, E., & Ghirotti, M. (2000). History of the 1963 Vaiont slide: The importance of geological factors. Bulletin of Engineering Geology and the Environment, 59(2), 87-97.

  • This paper emphasizes the importance of geological factors in the Vajont slide and provides a detailed history of the event.

Tika, T., & Hutchinson, J. N. (1999). Ring shear tests on soil from the Vaiont landslide slip surface. Geotechnique, 49(1), 59-74.

  • The authors conduct ring shear tests on soil samples from the Vajont landslide slip surface, providing insights into the soil mechanics of the slide.