New seismic tool from IIT Madras to test the safety of India's ageing dams

"Researchers from the Indian Institute of Technology (IIT) Madras have developed a first-of-its-kind computer programme designed to evaluate the earthquake vulnerability of India's vast network of more than 6,500 large dams. Prompted by the national requirements set forth in the Dam Safety Act of 2021, the scientists created a standalone software application that uses thousands of years of historic earthquake data to calculate highly precise, site-specific seismic risks. By analysing each dam's unique structural characteristics alongside local fault lines, the tool creates a more accurate hazard classification system to help authorities identify which infrastructure needs urgent safety upgrades."

"India is currently home to the third-highest number of large dams in the world. Crucially, more than 5% of these colossal concrete and earthen structures are over a century old, and an additional 20% have been standing for between fifty and one hundred years. Many of these reservoirs were constructed long before the advent of modern seismology and updated building codes. Furthermore, India sits on a highly complex tectonic landscape."

"The convergence of the Indian and Eurasian tectonic plates makes the Himalayan region incredibly active, while the ostensibly stable peninsular shield in the south has still produced devastating, highly destructive intraplate earthquakes in recent decades. As downstream populations have swelled over the years, a catastrophic dam failure triggered by a major seismic event would result in unimaginable tragedy."

"Historically, civil engineers in the country relied on simple deterministic zonation maps. These older methods chopped the vast nation into broad seismic zones, assigning a uniform hazard level and a generic peak ground acceleration to large regional swathes. This approach proved problematic because it completely ignored local variations in fault geometry, site-specific soil effects, and the statistical recurrence of major tremors."