MoRTH deploys InSAR-based early-warning systems to make Himalayan highways landslide-resilient

After cloudbursts and slope failures in the hills, the highways ministry is shifting from disaster response to prediction — using satellite radar monitoring on the Char Dham route and other vulnerable stretches.

What happened

• Following events like the devastating 2025 cloudburst in Uttarkashi's Dharali and Sukhi Top regions — which triggered flash floods and slope instability — the Ministry of Road Transport & Highways (MoRTH) is increasingly using advanced technologies to safeguard hill-road infrastructure.
• A key measure is the deployment of Interferometric Synthetic Aperture Radar (InSAR)-based landslide monitoring and early-warning systems along a 100-km stretch of the Char Dham route in Uttarakhand, enabling authorities to detect subtle ground movements and identify vulnerable slopes before disaster strikes.
• Complementing this are plans for an advanced warning and alert system on the Parwanoo-Solan section of NH-5 in Himachal Pradesh to monitor landslides, land sinking, groundwater movement and rockfall-prone zones in real time.
• MoRTH has strengthened institutional collaboration with scientific agencies, including an MoU with the Geological Survey of India (GSI) for geological investigations.
• Together, these reflect a shift from responding to disasters after they occur to predicting and preventing them — building a safer, more resilient highway network across India's hill states.

For Prelims

• InSAR (Interferometric Synthetic Aperture Radar): A satellite/radar remote-sensing technique that detects millimetre-scale ground deformation by comparing radar images over time — used here for early detection of slope movement and land subsidence.
• Landslides in the Himalaya: The young, fragile Himalaya are highly landslide-prone, worsened by cloudbursts, road-cutting, deforestation and seismicity; the Geological Survey of India (GSI) is the nodal agency for landslide hazard mapping (and runs the National Landslide Susceptibility Mapping).
• Cloudburst: Sudden, very intense localised rainfall (often >100 mm/hour) common in Himalayan terrain, triggering flash floods and landslides — e.g. the 2025 Uttarkashi (Dharali) event cited.
• Char Dham: The Char Dham road project connects Yamunotri, Gangotri, Kedarnath and Badrinath in Uttarakhand — strategically and religiously important, but cutting through fragile slopes.
• Geological Survey of India (GSI): An attached office of the Ministry of Mines; India's nodal agency for geological/landslide studies — MoRTH's scientific partner here.
• Disaster Management framework: The Disaster Management Act, 2005 and NDMA promote a shift from a relief-centric to a prevention/mitigation and preparedness approach — the framing of these MoRTH measures.
• Don't confuse: InSAR is a monitoring/early-warning (prediction) tool — not a physical slope-stabilisation structure; both are needed. The GSI (geology/hazard mapping) is distinct from the NDMA (disaster-management coordination).

For Mains

Syllabus: GS3.15 · GS3.9 · Linkage L2