ISRO releases before-and-after flashflood satellite images of Uttarkashi's Dharali village

The catastrophic flashflood that struck Dharali village in Uttarkashi district of Uttarakhand on August 5 has left behind a trail of devastation, now starkly visible in satellite images released by the Indian Space Research Organisation (ISRO).

Satellite Insights Aiding Rescue & Relief Ops

ISRO/NRSC used Cartosat-2S data to assess the devastating Aug 5 flash flood in Dharali & Harsil, Uttarakhand.

High-res imagery reveals submerged buildings, debris spread (Rs 20ha), & altered river paths, vital for rescue teams on… pic.twitter.com/ZK0u50NnYF

— ISRO (@isro) August 7, 2025

The National Remote Sensing Centre (NRSC), a division of ISRO, conducted a rapid damage assessment using high-resolution images from the Cartosat-2S satellite.

The comparison between June 13 and post-event images taken on August 7 reveals the true scale of destruction.

A massive fan-shaped deposit of sediment and debris, measuring approximately 750 metres by 450 meters and covering an area of about 20 hectares has formed at the confluence of the Kheer Ganga and Bhagirathi rivers.

This deposit is one of the clearest signs of the flood’s fury.

The satellite images also show:

Significant widening of stream channels

Altered river morphology

Extensive damage to infrastructure

Partial or complete destruction of numerous buildings

Several structures submerged or swept away by the mudflow and debris

ISRO noted that many buildings appear to be either entirely submerged or buried under mud and debris in Dharali village.

These satellite visuals would play a critical role in ongoing rescue and relief efforts, helping authorities identify isolated regions, locate stranded individuals and restore essential connectivity.

The flashflood struck around 1:30 PM on August 5 following intense rainfall, sweeping away homes, roads, bridges and lives.