From CK Nayak
NEW DELHI, March 9: Citing the ‘high cost’ of saving lives, the central government has scrapped its own upgraded earthquake safety norms for the Northeast, choosing to revert to older, weaker building standards after infrastructure departments and dam builders complained that making structures quake-proof in the region was becoming too expensive.
This move has drawn stiff opposition from its own infrastructure departments.
Surge in construction cost, inadequate consultation, project feasibility and administrative oversight are believed to be the main reasons for resending a major decision which would impact a large part of the country but mainly the Northeast and parts of Himalayan region.
Several government departments including the Ministry of Housing and Urban Development, Metro Rail corporations, National Dam Safety Authority (NDSA) and infrastructure authorities feared a surge in construction costs of projects nationwide. The infrastructure bodies have flagged the potential impact of the revised probabilistic seismic hazard assessment (PSHA) framework on construction costs.
The Bureau of Indian Standards (BIS) had issued a gazette notification on November 6, 2025, introducing revised earthquake hazard zoning under the updated IS 1893 (Part 1): 2025 code, which governs the earthquake-resistant design of structures. The revised standard was meant to replace the existing ‘IS 1893 (Part 1): 2016’ framework that currently guides structural design norms across the country.
However, the revised notification has been withdrawn through a fresh gazette notification issued on March 3 this year, effectively restoring the earlier code with immediate effect. The development also has major implications for most vulnerable areas like the Northeast and Himalayan region.
With the rollback, the country returns to the four-zone system with Zone V (Very High Risk) which includes the entire Northeast, parts of Jammu and Kashmir, Himachal Pradesh, Uttarakhand, the Rann of Kutch and the Andaman & Nicobar Islands.
Developers had warned that the revised zoning framework could disrupt financing for ongoing projects. Some even feared that several under-construction high-rise developments could risk turning into “stranded assets” if costs escalated sharply after financial closure.
The BIS notification issued in November last year significantly revised India’s seismic risk framework by incorporating updated PSHA-based modelling and new hazard parameters. Under the proposed classification, more than 60% of India’s landmass mostly in Himalayan belt would fall under moderate to high earthquake risk zones, representing a major shift in the country’s earlier seismic hazard mapping.
One of the most notable changes in the revised framework was the introduction of a new highest-risk ‘Zone VI’, bringing parts of Himalayas, the Northeast and the Kutch region of Gujarat under the most stringent seismic design standards. Several other regions across the Himalayan belt were categorised under Zone V, indicating very high seismic vulnerability.
Such changes would have required significant revisions in structural design standards for buildings and infrastructure projects, including stronger foundations, additional reinforcement in structural components and higher safety margins to withstand greater seismic forces.
The National Dam Safety Authority (NDSA) also reportedly raised scientific objections to the revised hazard values when the draft circulated among stakeholders in mid-2025. The NDSA said that the authority had examined the draft framework and found the proposed hazard parameters significantly higher than what its own assessments suggested.
Technical discussions within government agencies also raised questions about the methodology used in the revised probabilistic seismic hazard assessment. Experts acknowledged that the underlying scientific framework was robust but noted that the peak ground acceleration values proposed in the revised model were significantly higher than those typically used in international practice.
At high-level discussions following the November 2025 notification, experts pointed out that peak ground acceleration values in the revised framework were allowed to rise close to 1g, whereas global practice generally keeps them closer to 0.4g. This raised questions about whether India’s hazard parameters should be equated with highly seismic regions such as Japan or Taiwan.
The revised zoning map would have significant cost implications for infrastructure and real estate projects across the country. The builders would need to use more cement, steel and stronger foundation systems to meet revised structural safety standards.
However, around 42% of the country would have seen a one-zone increase, including parts of Gujarat, northern India and the Northeast, where the shift could have raised construction costs for buildings by 10-20% due to stricter design requirements.
The Northeast, other parts of Himalayan region and Gujarat would have experienced a two-zone increase, which officials said could push construction costs for residential and institutional buildings up by over 30%. This region is about 6% of the country’s total area.
Officials also warned that the impact would be particularly severe for dam infrastructure, where higher seismic hazard values could have pushed construction costs up by 10-20% in several regions. In highest-risk zones like the North East and other Himalayan regions the cost could be like 50% more because of stricter structural safety requirements.
The cost implications would have extended beyond large infrastructure projects to ordinary housing construction. Officials noted that nearly 80% of housing in India falls under what engineers classify as “non-engineered” construction — typically self-built homes constructed without formal structural design or engineering supervision.
While the real estate sector and government departments have hailed the move as a necessary economic relief, geologists and seismologists have criticised the rollback as a “missed opportunity” to improve disaster resilience in high-risk regions.
