[12th March 2026] The Hindu OpED: A seismic decision: On revision to India’s earthquake zoning, rollback 

Mentor’s Comment

The rollback of the Bureau of Indian Standards (BIS) revision of India’s earthquake zoning framework has revived debate over seismic risk assessment. The proposed revision sought to replace the simplified fixed seismic zoning model with probabilistic seismic hazard assessment, a method widely used globally. It also introduced a new high-risk Zone VI covering vulnerable regions such as Kashmir and the Himalayan belt. However, stricter zoning raised economic concerns, as construction costs could increase by about 20% with a one-zone rise and nearly one-third with two zones. 

Why does India require a revised earthquake zoning framework?

1. Urban Expansion and Risk Exposure: Rapid urbanisation increases population and infrastructure in seismically vulnerable areas. Large infrastructure such as metro systems, dams, highways, and power stations require updated seismic design standards.
2. Disaster Preparedness: Accurate zoning enables safer city planning, infrastructure design, and disaster management strategies. It reduces casualties and economic losses during earthquakes.
3. Climate and Disaster Resilience: Earthquake-resilient infrastructure contributes to broader climate-resilient development and sustainable cities.
4. Infrastructure Protection: Critical infrastructure projects must incorporate seismic design standards to prevent catastrophic failure during earthquakes.

What is the current earthquake zoning system in India?

1. Fixed Zoning Model: India currently uses a simplified seismic zoning map, dividing the country into fixed categories based on historical seismic activity.
2. Seismic Zones: India’s seismic classification includes Zones II, III, IV and V, with Zone V representing the highest risk areas.
3. Limitations of Fixed Zoning: Fixed zones rely heavily on past earthquake records and may not fully capture future seismic probabilities or micro-level risk variations.
4. Urban Planning Integration: These zones influence building codes, infrastructure design standards, and urban planning guidelines.

What changes were proposed in the BIS revision?

1. Probabilistic Seismic Hazard Assessment (PSHA): Introduces probability-based simulations to estimate earthquake intensity and frequency rather than relying solely on historical data.
2. Introduction of Zone VI: Adds a new highest-risk seismic zone, covering Kashmir, parts of the Himalayan belt, Kutch in Gujarat, and the northeast.
3. Improved Risk Modelling: Uses dynamic modelling of ground motion probabilities to improve earthquake preparedness.
4. Alignment with Global Practice: Aligns India’s seismic risk assessment methodology with advanced economies and seismically active regions worldwide.

Why did the proposed revision face opposition?

1. Economic Cost: Construction costs could rise significantly.
   1. One-zone increase: Costs may rise by around 20%.
   2. Two-zone increase: Costs may rise by nearly one-third.
2. Infrastructure Cost Escalation: High-value projects such as metro systems, dams, and power stations may face substantially higher structural design costs.
3. Development Concerns: Urban planners fear stricter zoning could slow infrastructure development in economically fragile regions.
4. Housing Informality: Nearly 80% of India’s housing stock lies in the informal sector, raising concerns that stricter regulations may increase unregulated construction.

What are the broader governance and policy challenges?

1. Institutional Coordination: The proposal faced resistance from multiple agencies including Ministry of Housing and Urban Affairs, Home Affairs, Central Water Commission, and National Dam Safety Authority.
2. Policy Consultation Gap: Large regulatory changes require extensive consultation across government agencies, industry stakeholders, and technical experts.
3. Balancing Safety and Affordability: Stricter building standards improve safety but increase construction costs and housing affordability pressures.
4. Implementation Capacity: Enforcement challenges remain significant due to informal housing markets and limited regulatory capacity.

How does the debate intersect with climate and sustainability goals?

1. Construction Sector Emissions: The construction sector is among the largest dispersed sources of carbon emissions in India.
2. Infrastructure Lifecycle: Seismic-resilient structures reduce the need for reconstruction after disasters, lowering long-term carbon and economic costs.
3. Resilient Urban Development: Disaster-proof infrastructure supports climate adaptation strategies and sustainable urbanisation.

Conclusion

Revising India’s earthquake zoning framework remains essential for ensuring disaster-resilient urban growth and infrastructure safety. However, scientific improvements must be accompanied by broad institutional consultation, economic feasibility assessments, and strong implementation mechanisms. A balanced framework that integrates advanced risk modelling with practical governance capacity is critical for strengthening India’s long-term disaster resilience.