Breakthrough achieved in Mumbai Metro Line 7A: 61% work completed, tunnel linking Andheri and airport reaches major milestone | Mumbai News

MUMBAI: The Mumbai Metro Line 7A project has hit a major milestone with the successful completion of a 1.65-km tunnel connecting Andheri (East) and Chhatrapati Shivaji Maharaj International Airport (CSMIA). On July 14, 2025, the tunnel boring machine (TBM) T-60 achieved the breakthrough, marking significant progress in this critical infrastructure project. Executed by the Mumbai Metropolitan Region Development Authority (MMRDA), tunneling began on September 1, 2023, with the TBM drive starting on November 4, 2023. The tunnel, with a finished diameter of 5.6 meters, was built using 1,178 rings — each 1.4 meters in length and made up of 6 segments. The depth of the tunnel ranges from 12 to 28 meters. The overall Metro Line 7A corridor spans 3.4 km, with a 2.5 km underground section. It includes two underground stations — Airport Colony and T2 Airport — and is designed as a partially elevated and partially underground alignment.

Once operational, the line will provide a seamless interchange at the CSMIA station with Metro Line 3, ensuring better connectivity for commuters. A senior official noted that passengers from Mira-Bhayander could reach BKC with just one interchange at the airport station. The project, targeted for completion in 2026, has now reached 61% completion. Key engineering challenges tackled include construction under the Sahar Elevated Road, an overpass above Metro Line 3, diversion of a major sewer line, and crossing an underground water pipeline. Metro Line 7A will eventually integrate with Metro Lines 2A, 7, 9, and 3, strengthening Mumbai’s metro network and easing travel across the city.