Why are India's river deltas sinking?

India's river deltas are sinking primarily due to human activities like unsustainable groundwater extraction and rapid urbanization, which accelerate natural geological processes.

What are the impacts of delta subsidence in India?

Delta subsidence leads to increased flooding, permanent land loss, saltwater intrusion into freshwater sources, and damage to infrastructure.

Which Indian deltas are affected by land sinking?

The Ganges-Brahmaputra, Brahmani, Mahanadi, Godavari, Cauvery, and Kabani deltas in India are confirmed to be sinking.

Home / Environment / India's deltas sinking due to human activity

India's deltas sinking due to human activity

22 Jan

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Summary

Indian river deltas are sinking primarily due to human activities.
Satellite data from 2014-2023 revealed significant land subsidence.
Subsidence causes increased flooding and saltwater intrusion.

India's deltas sinking due to human activity

A recent international study has revealed a significant and systemic drop in land elevation across India's major river deltas, with human activities identified as the primary cause. Researchers utilized data from the European Space Agency's Sentinel-1 satellite, collected between 2014 and 2023, to map subsidence rates.

Six Indian deltas, including the Ganges-Brahmaputra, Brahmani, Mahanadi, Godavari, Cauvery, and Kabani, were found to be sinking. In several of these, particularly the Ganges-Brahmaputra, Brahmani, and Mahanadi deltas, over 90% of their area is affected. The subsidence rates in some deltas even surpass the regional sea-level rise.

Unsustainable groundwater extraction is a major driver in the Ganges-Brahmaputra and Cauvery deltas, while rapid urbanization heavily impacts the Brahmani delta. The Mahanadi and Kabani deltas are affected by a combination of groundwater depletion, reduced sediment flow, and population pressure. Kolkata's subsidence is exacerbated by the city's immense weight and resource consumption.