Mumbai’s Metro expansion continues to gain momentum with Metro Line 7A, a pivotal extension aimed at improving connectivity to the Chhatrapati Shivaji Maharaj International Airport (CSMIA). Spearheaded by the Mumbai Metropolitan Region Development Authority (MMRDA), this line is set to transform airport access, linking distant suburbs to one of India’s busiest airports.
The project, projected for completion by December 2026, will be the third Metro line to connect the airport, following the operational Metro Line One and the upcoming Metro Line 3. Metro Line 7A extends the existing Line 7, which currently services the route from Andheri (East) to Dahisar (East). This southern extension will create a direct link from Andheri (East) to CSMIA, dramatically improving the travel experience for passengers heading to the airport.
Spanning 3.423 kilometres, the line features both elevated and underground sections, designed to navigate Mumbai’s dense urban environment. Upon completion, Line 7A is expected to reduce travel time to the airport from the Mira Bhayandar region and Western suburbs by up to 60 minutes. Its integration with Metro Line 3 and the future Metro Line 8 will further enhance the city’s transport network, ensuring seamless connectivity across Mumbai.
Construction progress on Metro Line 7A is robust, with over 52% of the work already completed. The line’s alignment presents unique engineering challenges, including its partial elevation along the Western Express Highway (WEH) and Sahar Elevated Road, with an elevated station at Airport Colony. The alignment then transitions underground to a station positioned adjacent to Terminal 2, strategically near the CSMIA Metro Line 3 station. Key milestones in the project include the transfer of land from the Airports Authority of India (AAI) in October 2021 and the successful relocation of the Valmiki Nagar and Bamanwada slum in Vile Parle, which was completed by May 2022.
Additionally, the relocation of Purushottam Giri Ashram and temple, and the diversion of critical utilities, including an 1800 mm underground sewer line, were achieved using advanced micro-tunnelling techniques. Ongoing work includes the diversion of a 2400 mm water line in coordination with the Brihanmumbai Municipal Corporation (BMC). The construction involves the use of a Dual Mode Hard Rock Tunnel Boring Machine (TBM), specifically designed for Mumbai’s rocky terrain. With an average mining rate of 4 to 5 metres per day, the TBM’s cutter head measures 6.68 metres in diameter, facilitating the complex tunnelling work.
The twin tunnels, each with a diameter of 6 metres, will be lined with precast segments to ensure structural integrity. Metro Line 7A is set to offer considerable environmental benefits by reducing fuel consumption and CO2 emissions, thus contributing to improved air quality in Mumbai. The design of the CSMIA underground station includes strategic connections at the concourse level to Metro Line 3’s station and direct access to Terminal 2, providing unmatched convenience for airport passengers.
As Mumbai’s infrastructure continues to evolve, projects like Metro Line 7A are crucial in positioning the city as a leader in urban mobility and infrastructure development. “Enhancing connectivity to a key city gateway, this project is integral to supporting Mumbai’s future growth,” stated an MMRDA Commissioner.
