Proposed Tunnel Road (TRP) starts over 1 km after Central Silk Board (CSB) near St John’s Hospital and extends 16.6 km to Hebbal—the same distance as via surface roads. A current claim is that the 80–90 minutes using present roads will reduce to ~35 minutes via the tunnel. Other stated benefits include reduced commute cost, air and noise pollution.

Relevant Factors

• With TRP in place, CSB junction must still be crossed via surface roads in both directions since the start and end points of the tunnels are on the city side of CSB.
• Inside the tunnel, with a 60 km/h speed limit, average speed may be ~50 km/h or less. The slowest vehicle will set the pace.
• Entry/exit ramps interface traffic moving at ~50 km/h with surface traffic at ~15–20 km/h. These merges can cause congestion or gridlocks.
• Many tunnel-using cars may need U-turns before entry and after exit, further increasing surface congestion.
• Toll of ~₹20/km (more than double the per-km cost of petrol/diesel) applies for entry ramp + tunnel + exit ramp. Estimated full-length toll: ~₹320 each way.
• No provision for commute between CSB and Lalbagh/Jayanagar since no entry/exit is provided at Lalbagh from/to CSB.
• Construction planned for 5 years—likely to extend—will disrupt services and traffic.
• Water aquifers, wells, borewells, and lakes may be adversely affected.
• Any traffic hold-up inside the tunnel or near ramps (breakdowns, incidents) could trigger gridlock/accidents both inside and outside.
• Metro Yellow Line is functional and targeted for full services by end-2026; possible extension to Attibele. Pink Line (Bannerghatta Road–Nagawara) ~2026–27. CSB–Airport Metro ~2027–28. These lines should significantly reduce congestion.
• Metro between Sarjapura and Hebbal (awaiting final sanction) shares a similar corridor and could drastically reduce traffic along the tunnel alignment.
• Track-doubling between Baiyyappanahalli and Hosur (~2026) and Suburban Rail (Heelalige–Rajankunte, ~2028) can positively impact Hosur Road traffic.
• Emerging options for airport commute: air taxis, helicopters, drone taxis, etc.
• Proposed airport at Hosur could reduce CSB congestion.
• TRP is non-inclusive: ~80% of vehicles in Bengaluru may not qualify to use it; many car owners may not afford the toll.
• Conclusion from this view: TRP may be exorbitantly costly, eco-unfriendly, unsafe, and highly disruptive—potentially increasing overall congestion, commute time, and cost.

Suggested Priorities for Bengaluru