Mumbai: After shelving its Marine Drive road widening plan, the Mumbai Metropolitan Region Development Authority (MMRDA) has now proposed altering the alignment of the Orange Gate-Marine Drive twin tunnel project to prevent a potential bottleneck near Jawahar Bal Bhavan at Charni Road, according to officials familiar with the matter.Part of the promenade was already widened during the construction of the Mumbai Coastal Road (South), which was inaugurated in March 2024. (Bhushan Koyande/HT Photo)The revised alignment would require reclaiming 2,298 square metres of land—around one-third the size of a football ground—from the Arabian Sea near the Pransukhlal Mafatlal Hindu Swimming Bath & Boating Club Trust, according to the proposal documents accessed by HT.This means the Marine Drive promenade will have to be moved farther into the Arabian Sea. Part of the promenade was already widened during the construction of the Mumbai Coastal Road (South), which was inaugurated in March 2024.Officials said the modification would increase the project’s cost by around ₹40 crore. The Orange Gate-Marine Drive twin tunnel project was approved in March 2023 at an estimated cost of ₹8,056 crore.According to officials, the road widening is necessary to increase the number of lanes outside Jawahar Bal Bhavan from the existing eight (four in each direction) to 13. The twin tunnel project will have entry and exit ramps near Jawahar Bal Bhavan, where vehicles entering and exiting the tunnels will merge with existing traffic. Approximately 300 metres of road between the Coastal Road’s entry-exit points and the Mafatlal swimming pool will need to be widened, said an MMRDA official, requesting anonymity.The proposed 13 lanes would be divided into four categories, officials said. The existing four Nariman Point-bound lanes will be reduced to three. There will be three lanes for vehicles exiting the twin tunnel and headed to Nariman Point. Likewise, there will be another three lanes for vehicles coming from Nariman Point to enter the Orange Gate-bound tunnel. For the traffic headed towards Girgaum Chowpatty, there will be four lanes.Over the last couple of months, MMRDA has begun the process of obtaining environmental clearance for the revised design. The proposal has been submitted to the Maharashtra Coastal Zone Management Authority (MCZMA), which functions under the state’s environment and climate change department.As HT reported earlier this month, MMRDA has put its Marine Drive road-widening project on the back burner after residents pushed back. MMRDA officials had said they wanted to first study the traffic impact on Marine Drive once the twin tunnels became operational, and then initiate the proposed project accordingly. The under-construction twin-tunnel project is scheduled to be completed in June 2028.As per the original plan, the authorities planned to widen a stretch of Marine Drive, from the Coastal Road entry/exit to the National Centre for the Performing Arts (NCPA), from the existing six lanes to 12. Chief minister Devendra Fadnavis had approved this proposal in April 2025, but it will remain on paper for now.