🌧️ Brihanmumbai Municipal Corporation Begins Trenchless Drain Upgrade to Strengthen Flood Control in Mumbai Mumbai: In a major step towards improving flood management, the Brihanmumbai Municipal Corporation (BMC) has initiated an ambitious project to upgrade the city’s ageing stormwater drainage system using advanced trenchless technology. The initiative focuses on reinforcing more than a century-old underground arch drains across Mumbai through geopolymer lining, a modern technique that enhances structural strength while increasing water-carrying capacity. Officials estimate that the upgrade could extend the lifespan of these drains by at least 50 years. Addressing Ageing Infrastructure Much of Mumbai’s drainage network dates back to the British era and has been under increasing pressure due to rapid urbanisation and frequent extreme rainfall. The city’s coastal geography, combined with tidal influences from the Arabian Sea, further complicates water discharge during heavy rains. According to civic data, Mumbai’s stormwater drainage network spans approximately 621 km, including 495 km in the island city and additional stretches in the eastern and western suburbs. Recent CCTV inspections revealed serious structural issues such as cracks, damaged joints, displaced bricks, and even partial collapses in several sections. Priority Repairs Under Phase 1 Based on these findings, 56 arch drains covering 23.5 km were identified as critically damaged. Of these, 27 drains spanning 14.28 km have been prioritised under Phase 1 of the project. Currently, repair work is underway across key stretches in South Mumbai. Senior officials, including Deputy Municipal Commissioner Girish Nikam and Chief Engineer Kalpana Raut, have conducted on-site inspections to monitor progress and ensure timely execution. Trenchless Technology: A Game Changer The use of trenchless technology allows the BMC to repair underground drains without extensive excavation, significantly reducing disruption to traffic and daily life in densely populated areas. The geopolymer lining method also improves internal flow, enabling faster discharge of rainwater during heavy downpours. This approach was finalised after consultations with experts from Indian Institute of Technology Bombay and Veermata Jijabai Technological Institute, making it one of the first large-scale implementations of its kind in India. Boosting Flood Preparedness In recent years, Mumbai has experienced intense rainfall events, sometimes recording nearly 1,000 mm within a few days, leading to severe waterlogging in low-lying areas. Officials believe that the upgraded drainage system will significantly improve flood resilience by ensuring quicker and more efficient water flow. Sustainable Long-Term Solution Apart from durability, geopolymer materials are considered environmentally sustainable, offering a long-term solution for infrastructure rehabilitation. The BMC plans to use the success of this phase as a model for upgrading other vulnerable sections across the city. Conclusion With monsoon patterns becoming increasingly unpredictable, this proactive initiative by the Brihanmumbai Municipal Corporation marks a crucial step towards safeguarding Mumbai from flooding. By combining modern technology with strategic planning, the city aims to strengthen its infrastructure and enhance resilience against extreme weather conditions.
