Mumbai: In a first for an urban local body in Asia, the Brihanmumbai Municipal Corporation (BMC) in January approved through its high-rise committee (HRC) for empanelment of geotechnical/foundation experts to scrutinise as independent signatory for the foundations of high-rise buildings and ensure that excavation and construction practices meet stringent safety standards. The new norm states that buildings taller than 180m will have to obtain a mandatory clearance from HRC before key stages of construction can proceed.The move comes as Mumbai’s skyline grows increasingly vertical, with a rising number of super-tall towers being planned on tightly packed urban plots that require deep excavations and complex foundation systems. Palais Royale in Worli is Mumbai’s tallest under-construction building at 320m. Lokhandwala Minerva, Piramal Aranya Arav, Lodha World One, and others shape Mumbai’s skyline, with many other proposals in queue.“This is a big step in ensuring the safety of building foundations. Our high-rise committee examines whether the foundation design is appropriate for the soil/rock conditions, whether excavation is being carried out safely, and whether adequate safeguards are in place to prevent damage to nearby buildings and underground utilities,” said IIT- Bombay’s civil engineering department Deepankar Choudhury, who is a member of BMC’s HRC and a geotechnical/foundation expert. “This includes reviewing soil/rock investigation reports, shoring systems, and other measures deployed during deep digging for basements and foundations.”Until now, these aspects were largely reviewed and signed by structural engineers appointed by developers as part of the building approval process.However, a series of structural failures of foundations or shorings in recent years that pointed to lapses in foundation quality prompted the BMC to consider specialised oversight from geotechnical consultants as independent signatory taking responsibility of foundation/geotechnical design.Choudhury said the committee to empanel geotechnical consultants will include independent senior geotechnical engineers from academia and industry with aligned technical specialisation who will provide the much-needed an additional layer of scrutiny before work proceeds on projects involving deep foundations. “With dense construction often taking place only metres away from existing buildings, excavation can pose significant risks if not carefully monitored,” he added.By bringing in independent expert geotechnical/foundation review at the municipal level, the BMC hopes to reduce such risks and ensure that foundation construction for super-tall buildings follows the highest engineering standards.Choudhury said the initiative could set a precedent for other cities grappling with the challenges of rapid vertical growth.
