India’s Earthquake Zoning Debate: Balancing Safety, Development and Climate Goals
Why in News?
The Government of India rolled back the proposed revision of earthquake zoning norms prepared by the Bureau of Indian Standards.
The revision attempted to adopt a probability-based seismic risk assessment and proposed a new Zone VI, covering high-risk areas such as:
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Kashmir
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Parts of the Himalayan region
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Kutch in Gujarat
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North-East India
However, the framework was withdrawn due to concerns regarding high construction costs, development delays, and policy implications.
What is Earthquake Zoning?
Earthquake zoning divides a country into regions based on seismic hazard risk.
The zoning determines:
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Building design standards
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Infrastructure safety norms
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Urban planning guidelines
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Disaster preparedness strategies
India currently follows four seismic zones under BIS guidelines:
| Zone | Risk Level |
|---|---|
| Zone II | Low risk |
| Zone III | Moderate risk |
| Zone IV | High risk |
| Zone V | Very high risk |
The proposed revision introduced Zone VI (extreme risk).
Why Was the Revision Proposed?
India’s current seismic zoning system is considered simplistic and outdated.
The proposed update aimed to shift towards a modern method called Probabilistic Seismic Hazard Assessment (PSHA).
What is PSHA?
PSHA is a probability-based seismic risk model.
It estimates the likelihood of earthquakes of different magnitudes occurring at a location over time.
Instead of a fixed zone, it considers:
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Fault lines
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Earthquake history
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Ground motion probability
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Geological conditions
Many earthquake-prone countries such as Japan and the United States use this method.
Concerns Raised Against the New Zoning
1. Increased Construction Costs
Stricter seismic standards mean stronger structures.
Estimated cost increase:
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20% increase for a one-zone jump
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Up to 30–35% increase for two-zone changes
For infrastructure like:
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Metro systems
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Dams
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Power plants
costs could rise significantly.
2. Impact on Development
Regions likely to fall into Zone VI include economically sensitive areas such as:
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Himalayan states
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North-East India
Urban planners fear that strict norms could:
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Slow infrastructure development
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Reduce investment
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Increase housing shortages
3. Expansion of Informal Housing
India already has nearly 80% of homes in the informal sector.
Higher compliance costs could push people to build unsafe, unregulated structures, increasing disaster vulnerability.
4. Inter-Ministerial Concerns
Several government bodies raised objections, including:
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Ministry of Housing and Urban Affairs
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Ministry of Home Affairs
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Central Water Commission
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National Dam Safety Authority
Climate Dimension
Earthquake-resistant construction also has climate implications.
The construction sector:
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Is one of India’s largest sources of carbon emissions
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Uses energy-intensive materials like cement and steel
Stricter seismic standards could increase:
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Material use
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Construction emissions
Thus, policymakers must balance disaster resilience with climate mitigation.
Why Earthquake Zoning Matters for India
India is highly vulnerable to earthquakes.
About 59% of India’s land area is prone to moderate or severe seismic risk.
Major earthquake-prone regions include:
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Himalayan belt
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Indo-Gangetic plains
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North-East India
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Kutch region
Recent disasters highlight the need for stronger building codes.
Importance for Urban Infrastructure
India is undergoing rapid urbanisation and infrastructure expansion.
Projects affected by seismic norms include:
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Smart cities
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Metro rail
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Dams and hydropower
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Highways
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Power infrastructure
Correct zoning ensures future resilience of urban infrastructure.
Way Forward
A balanced approach is required:
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Gradual implementation of seismic norms
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Better consultation with engineers and urban planners
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Integration with climate-friendly construction technologies
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Strengthening building code enforcement
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Retrofitting vulnerable buildings
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Promoting earthquake-resilient affordable housing
UPSC Previous Year Question (PYQ)
UPSC Prelims 2015
Which of the following regions of India are most vulnerable to earthquakes?
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Himalayan region
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Indo-Gangetic plains
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Western Ghats
Answer: 1 and 2
Possible UPSC Prelims MCQ
Consider the following statements regarding earthquake zoning in India:
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India currently follows five seismic zones.
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Probabilistic Seismic Hazard Assessment (PSHA) uses probability-based modelling of earthquake risk.
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Nearly 60% of India’s land area is vulnerable to earthquakes.
Which of the statements given above are correct?
Answer: B
Conclusion
India’s earthquake zoning revision highlights the complex trade-off between safety, development, affordability and climate goals.
As India expands its urban infrastructure, adopting scientifically sound and implementable seismic standards will be crucial for building resilient and sustainable cities.
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