Overview
- The second TBM, Vihar, began excavation on November 7 and has joined the first machine Tulshi so both tunnels under Sanjay Gandhi National Park are now being bored simultaneously.
- Tulshi has already advanced more than 270 metres along its drive and project teams plan to raise tunnelling speeds as conditions allow.
- Both TBMs use Single Shield Earth Pressure Balance technology; Vihar features a 14.49-metre cutter head and an overall length of about 83 metres with a multi-level backup gantry.
- Each tunnel will total 6,675 metres with 5.34 km to be TBM-driven, a 13-metre internal diameter and three traffic lanes per bore to create six lanes of underground east–west connectivity.
- Work at the Mulund shaft has seen 612 of 743 structures cleared with the remaining 131 due by December 2026 or early January 2027 and rehousing at Kanjurmarg underway while the BMC directs safety, muck management and resource reviews to meet the February 2029 target and cut cross-city travel from roughly 90 minutes to about 20 minutes once open.