Answer

Introduction

India lies at the collision boundary of the Indian and Eurasian plates, with Delhi in Seismic Zone IV and the Northeast in Zone V. As per the National Center for Seismology (NCS), the July 10, 2025, Delhi tremor (magnitude 4.4) revealed how over 80% of buildings in Delhi remain non-compliant with seismic codes, highlighting urgent gaps in preparedness.

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Causes of Seismic Vulnerability

• Tectonic Setting and Plate Collision: India’s northward drift at 4–5 cm/year causes high seismic stress along the Himalayan belt.
• Shallow Earthquakes with High Impact Potential: Moderate magnitude quakes at shallow depths cause more surface damage.
  Eg: July 2025 Delhi quake (4.4 magnitude, 5 km depth) exposed fragility of infrastructure.
• Historical Seismic Activity: Previous major earthquakes show recurring risk in the Indian subcontinent.
  Eg: 2001 Bhuj (7.7 magnitude, 20,000+ deaths), 2015 Nepal (7.8 magnitude), recent Mandalay quake (7.7) in March 2025.
• Seismic Zones Cover Vast Populated Areas: Zones II–V span across densely populated regions with inadequate retrofitting.
  Eg: Northeast states like Mizoram, Nagaland, and Manipur lie in Seismic Zone V (PGA > 0.36g).
• Soft Soil and Liquefaction-Prone Zones: Soils in many urban areas amplify shaking, increasing structural vulnerability.
• Global Seismic Unrest Reflects Rising Risk: Rising tremors globally indicate dynamic tectonic conditions.
  Eg: Quakes in Greece (6.2 magnitude, May 2025), Indonesia, Chile, and Ecuador hint at tectonic instability.
  

Challenges to Earthquake Resilience in Urban India

• Non-Compliance with Building Codes: Majority of buildings lack seismic resistance features.
  Eg: Over 80% of Delhi buildings, especially pre-2000, don’t follow IS seismic code.
• Rapid and Unregulated Urbanisation: Expansion outpaces planning, especially in high-risk zones.
• Enforcement and Awareness Gaps: Seismic laws exist but are poorly implemented at local levels.
  Eg: Unlike Bangkok’s updated codes post-2007, India’s enforcement remains patchy.
• Lack of Real-Time Preparedness: Early warning systems are underused and public education is weak.
  Eg: NCS’s IndiaQuake app exists, but public and institutional awareness lags.
• Vulnerable Legacy Infrastructure: Older buildings remain structurally weak and unretrofitted.
  Eg: Buildings in Bhuj and Guwahati lack ductility and are built on unstable soils.
• Lack of Community-Level Disaster Planning: Limited training and response teams delay mitigation.

Policy and Infrastructural Measures

• Mandatory Retrofitting in High-Risk Zones: Implement steel jacketing, shear walls, and base isolation in legacy buildings.
  Eg: Delhi Development Authority must retrofit structures pre-dating 2000.
• Strict Enforcement of IS 1893:2016: Ensure building designs in all seismic zones comply with latest standards.
  Eg: Guwahati in Zone V must avoid floodplain construction and adopt deep pile foundations.
• Strengthen Early Warning and Monitoring Systems: Expand IndiaQuake coverage and integrate it with municipal alert systems.
• Public Awareness Campaigns and Safety Drills: Educate people about emergency kits, safe exits, and evacuation plans.
• Incentivise Seismic-Resilient Construction: Subsidies or tax rebates for earthquake-resilient construction in private buildings.
  Eg: Investments of ₹50,000 crore annually needed for retrofitting as per expert estimates.
• National Seismic Resilience Mission: Launch a centralised mission integrating state and urban bodies for seismic safety.
  

Conclusion

The 2025 tremors are a critical reminder of the seismic risks India’s cities face. Building resilience requires enforcing codes, retrofitting old infrastructure, raising awareness, and investing in seismic research. Lessons from Bhuj, Nepal, and Myanmar must drive proactive planning before the next disaster strikes  for India, it’s not a question of “if” but “when.”

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