Changes in India’s seismic design standards notified by the Bureau of Indian Standards (BIS) in November last year have prompted Gurugram Metro Rail Limited (GMRL) to revise the structural design of the entire Gurugram metro alignment, with stronger safety measures being incorporated into piles, pillars and stations, officials said.
Metro officials said designs for piles, pillars and stations are being updated to meet specifications under the new seismic zone notification issued by BIS. Additional designers and planners have been deployed to rework structural designs, though officials said efforts are being made to ensure the revisions do not affect construction timelines.
As per GMRL officials, the cost of revision in design is being estimated but it won’t have any significant increase in the project cost as the construction has just started. The metro corporation said that they are taking steps to ensure the timelines are not impacted for the first phase. Only structural design needs to be revised, they added.
According to the revised seismic design standard IS 1893 (Part 1):2025 and Part 5:2025 issued on November 3, 2025, most new projects are expected to be designed to zone five safety levels, even though the region remains officially in zone four. Experts said the norms require stronger reinforcement and ductile detailing, thicker structural walls, stiffer frames and deeper, more resilient foundations. The updated code replaces the 2016 version and is mandatory for all new construction nationwide, including Delhi NCR.
A senior GMRL official said the structural design of pillars, piles, spans and other components is being updated to meet zone five specifications. “Our job has become difficult and more time taking as all structures are being redesigned. The design softwares earlier were using seismic zone four specifications as base but now these are being updated. The design will ensure that the structures will be more resilient and tolerate stronger earthquakes,” the official said, adding that the revised parameters will be incorporated into the phase two tender.
An official of Systra, the design consultant for the metro, confirmed the changes. “This means deeper deeper bores, heavier reinforcement and more strength in the structures. This will cost more time and resources but the structures will be ready to to meet any eventuality,” he said.
Yogesh Bhasin, president, Structures. Signature Global, said the revised zoning effectively requires Delhi NCR to meet zone five specifications. “In seismic-prone regions like Delhi-NCR better design of structures, introducing vibrant control equipment, better reinforcement was key for safety. Meeting zone five parameters meeans we are ready for earthquakes measuring 7 on the richter scale. Doing it in the metro project at the design stage is a positive step,” he said.
Naveet Kour, scientist at Central Road Research Institute, said adopting the new code will improve earthquake safety. “Delhi NCR is practically in Zone five seismic category and the construction practices will have to be followed as per the new design code,” she said.