The Shirur landslide of July 2024 triggered by intense rainfall and unchecked development

Abstract

On the morning of July 16, 2024, a significant landslide occurred in Shirur of Uttara Kannada district, Karnataka, India. The landslide claimed seven lives, leaving one person missing and severely disrupting the transport network by blocking National Highway 66. The displaced debris travelled 180m across the highway and into the Gangavali River, causing a significant splash and damaging structures on the opposite bank. The event, characterised by a rotational slip, was triggered by a combination of anthropogenic activities and intense rainfall. The construction of National Highway 66, which involved the removal of the slope's toe without adequate protection for the excavation, significantly destabilised the area. On 15th July, the rain gauge in Ankola recorded rainfall of 260 ​mm. The accumulated rainfall calculated for Shirur using Inverse Distance Weightage (IDW) for the storm period of 4 days was 198 ​mm, which increased the pore water pressure within the soil, weakening its shear strength and leading to slope failure. This incident underscores the need for further analysis and the implementation of appropriate mitigation measures, as the region remains at risk for future landslides. The Shirur landslide serves as a critical reminder of the dynamic nature of such disasters, particularly when human activities exacerbate natural hazards.