Thane–Borivali Tunnel Project: Redefining Urban Connectivity in Mumbai

As India pushes forward with transformative urban infrastructure, the Thane–Borivali Tunnel Project stands out as a landmark development that promises to reshape intra-city mobility in Mumbai. Spearheaded by the Mumbai Metropolitan Region Development Authority (MMRDA), the project exemplifies modern tunneling engineering and integrated urban planning.

Project Specifications and Scope

Designed to ease the chronic traffic congestion between Thane (eastern suburbs) and Borivali (western suburbs), the project comprises twin three-lane road tunnels extending 10.8 km under the ecologically sensitive Sanjay Gandhi National Park (SGNP). Including approach roads, the project spans a total of 11.84 km.

• Estimated Cost: ₹13,200 crore
• Construction Depth: Up to 23 meters below ground
• Primary Contractor: Megha Engineering & Infrastructures Ltd. (MEIL)
• Project Management Consultant (PMC): Hill International
• Expected Completion: 2029

The twin tunnels will significantly cut travel time from the current 1–2 hours to approximately 15 minutes, transforming commute dynamics between key suburban nodes.

Engineering Excellence

At the heart of this project is the deployment of four state-of-the-art Tunnel Boring Machines (TBMs) supplied by Herrenknecht, a German tunneling technology firm known for precision engineering in complex terrains. The first TBM, S1400A, successfully completed its Factory Acceptance Test (FAT) in February 2025, marking a major pre-construction milestone.

Each tunnel will feature three lanes, ensuring high-capacity throughput and allowing for smooth vehicular movement even during peak hours.

Environmental Sensitivity and Compliance

Given the tunnel’s alignment beneath SGNP—a rich biodiversity reserve—environmental assessments have been central to project planning. The National Board for Wildlife (NBWL) granted conditional approval in October 2023, mandating a detailed impact study.

The Wildlife Institute of India (WII) is currently conducting a two-year-long multidisciplinary study, assessing geological, ecological, and hydrological parameters. These evaluations will guide protective measures to ensure minimal disruption to the park’s fragile ecosystem.

Urban Mobility and Strategic Significance

The existing commute between Thane and Borivali requires navigating the congested Ghodbunder Road corridor, often resulting in significant travel delays. The new tunnel corridor eliminates this detour by offering a direct east–west underground link. Upon completion, this infrastructure will not only slash travel times but also reduce vehicular emissions and alleviate surface congestion.

This development aligns with broader objectives in Mumbai’s urban masterplan—promoting seamless, sustainable mobility while enabling decongestion of arterial routes.

Conclusion

The Thane–Borivali Tunnel Project is a bold step toward modernizing Mumbai’s transportation backbone. It reflects the convergence of high-end engineering, strategic urban planning, and environmental stewardship. As construction progresses and tunneling operations commence, the project is set to become a national benchmark for sustainable urban infrastructure.