Bengaluru Clears Rs 420 Bn Silk Board–Hebbal Tunnel Plan

The 16.68-kilometre tunnel road planned between Central Silk Board and Hebbal, near Esteem Mall, will run some 36 metres (120 feet) below ground. Bengaluru Smart Infrastructure Ltd (B-SMILE), the special-purpose vehicle set up for major projects, will open the two-package tender within days after receiving state finance clearance on 9 June.

Advanced tunnel-boring machines will drive the four-year build, and cars will pay a toll initially set at Rs 19 per kilometre—about Rs 320 for a full journey—though the tariff may rise with inflation and final cost. B-SMILE director B S Prahallad insisted surface buildings would remain safe but acknowledged that “some borewell points may be impacted”; groundwater belongs to the state, he added.

Total investment is estimated at about Rs 420 billion, including Rs 8 billion for land. Critics, however, question the economics. Bengaluru Central MP P C Mohan warned that taxpayers face a Rs 71 billion subsidy and Rs 107 billion in state-backed loans, asking why private capital “stays away” if the scheme is viable. Congestion at tunnel exits and higher pollution are “inevitable”, he claimed.

Geologists, meanwhile, fear tunnelling could disturb natural dykes and fracture zones that feed borewells. Former Bengaluru University professor T J Renuka Prasad cautioned that miscalculations might destabilise the tunnel or alter aquifer flows, potentially affecting metro corridors.

Despite the controversy, Chief Minister-led planners argue the project will ease chronic gridlock on surface roads and form a backbone for future smart-mobility networks across the Karnataka capital.