Bengaluru’s ₹17,800 crore twin-tube tunnel road project faces growing opposition over environmental risks, Lalbagh land concerns, and technical flaws, sparking citizen protests, court petitions, and a political showdown.
The proposed twin-tube tunnel road project, stretching nearly 17 kilometres from Hebbal (Esteem Mall Junction) to Central Silk Board, has become one of the most hotly debated infrastructure plans in the city’s history. Designed as an underground expressway, the project aims to ease Bengaluru’s notorious traffic congestion by diverting vehicles below the surface and connecting two of its busiest corridors.
The Karnataka government, led by Deputy Chief Minister DK Shivakumar, has pitched the project as a “transformative mobility solution” that will shorten travel times and decongest arterial roads. The tunnel will run deep beneath the city, carrying motor vehicles through a modern, signal-free corridor equipped with ventilation systems, safety exits, and emergency facilities.
The project is planned under a Public-Private Partnership (PPP) model, specifically the Build, Own, Operate and Transfer (BOOT) framework. This means private concessionaires will finance, construct, and operate the tunnels for a defined period before transferring them to the state.
How Much Will It Cost?
According to official estimates and media reports, the tunnel is expected to cost around ₹17,700 to ₹17,800 crore. The plan divides the corridor into several work packages, and the government expects private bidders to recover their investment through toll collection once the road becomes operational.
Why the Tunnel Road Has Become a Flashpoint?
Technical and Planning Concerns
A technical expert panel appointed by the Karnataka government has raised serious red flags about the project’s planning and feasibility. The Detailed Project Report (DPR), the committee found, contained major deficiencies in key engineering and design parameters.
The experts pointed to insufficient soil and rock testing, inadequate groundwater mapping, and unclear traffic projections. The DPR also failed to detail crucial systems for stormwater management, fire safety, disaster response, and ventilation.
The committee concluded that the DPR was inadequate to establish the project’s technical and financial viability and recommended a complete rework of the alignment, cost estimates, and traffic assumptions before tenders are floated.
Environmental and Heritage Risks: Lalbagh in the Crosshairs
The most controversial part of the project is the proposed alignment that passes directly beneath Lalbagh Botanical Garden, Bengaluru’s 240-acre green lung and one of its most iconic heritage sites.
Blueprints indicate that around six acres of Lalbagh land could be affected along a 1.1 km stretch of Siddapura Road, between Ashoka Pillar and Marigowda Junction. Two massive tunnels, each roughly 15 metres in diameter, are planned here, along with entry and exit ramps and a large ventilation shaft located within Lalbagh’s premises.
Experts warn that tunnelling under Lalbagh Rock, a three-billion-year-old Peninsular Gneiss formation recognised as a National Geological Monument, could have irreversible effects on groundwater systems and the park’s ecological balance.
Renowned environmentalist Dr. Yellappa Reddy cautioned that disturbing the ancient rock could lead to seepage from Lalbagh Lake and destabilise the surrounding areas, including the NIMHANS complex.
Citizen groups such as Citizens for Citizens (C4C) have voiced fears that the tunnel’s proposed ventilation shaft, described as a “chimney”, could expel toxic gases and heat, degrading air quality and threatening Lalbagh’s flora and fauna.
Equity and Urban Planning Concerns
Urban mobility experts have criticised the project as “car-centric” and socially inequitable, arguing that it prioritises private vehicles while neglecting mass transit systems like the metro and BMTC.
Data shows that only about 12 percent of Bengaluru’s population owns cars, while the majority depend on buses, two-wheelers, and shared mobility. Critics argue that investing nearly ₹18,000 crore in an underground road instead of strengthening public transport is a misplaced priority.
The proposed toll fee of around ₹330 per trip is also a major point of contention, with activists claiming it will make the facility accessible only to the wealthy. The DPR’s lack of integration with bus corridors or metro connectivity has deepened these concerns.
State Government’s Expert Committee Findings on the Tunnel Project
The state’s own expert review committee, tasked with evaluating the DPR and project feasibility, issued a detailed critique highlighting multiple deficiencies across engineering, design, and planning domains.
Alignment and Environmental Concerns
- Tunnel alignment runs too close to Metro lines, raising concerns about redundancy and safety.
- The proposed ventilation shaft within Lalbagh should be reconsidered due to the park’s eco-sensitivity.
- Entry and exit ramps could worsen surface traffic; the committee suggested redesigning junctions and widening connecting roads.
- The Mehkri Circle ramp design violates standard norms and requires conversion to a two-lane layout.
- The Hebbal nallah diversion is unrealistic and needs a complete redesign.
Drainage and Geotechnical Studies
- No detailed drainage plan has been prepared.
- Soil and groundwater data are incomplete; full geotechnical investigations are mandatory before proceeding.
Traffic and Planning Issues
- The DPR lacks 25-year traffic projections and mode-share data (public versus private transport).
- Project viability remains unclear given overlaps with Metro routes.
Design and Construction Challenges
- Timelines are unrealistic, with land acquisition and utility shifting not accounted for.
- Designs for tunnel boring machines (TBM), ventilation, fire safety, and lighting require major revision.
- Floatation, creep, and temperature loads have not been factored into the design.
Cost and Operations & Maintenance (O&M) Gaps
- Cost estimates are based on a single vendor’s quotation, missing key financial components.
- Grouting, muck disposal, and TBM costs are not properly detailed.
- Land acquisition, utilities relocation, EIA, and disaster management are absent from the DPR.
Committee Recommendations
- Revise the DPR with complete studies and realistic schedules.
- Secure 90% right-of-way (ROW) before starting any construction.
- Use abandoned quarries for muck disposal to prevent environmental damage.
- Form a single-window technical oversight committee to monitor DPR revisions and project execution.
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Political Theatre: DK Shivakumar vs. Tejasvi Surya
What began as a technical issue has now turned into a full-blown political confrontation.
Deputy Chief Minister DK Shivakumar has strongly defended the project, describing it as a forward-looking step for Bengaluru’s infrastructure. He has repeatedly asserted that “tunnels are the future of modern cities”, insisting that no trees will be cut and that the government will adopt global best practices to minimise environmental impact. Shivakumar maintains that the tunnel will ease traffic congestion and improve urban mobility without harming green spaces.
On the other hand, Bengaluru South MP Tejasvi Surya has emerged as one of the most vocal critics. Calling the project “unscientific and anti-Bengaluru”, he argues that the proposed tunnel will create 22 new choke points instead of reducing congestion, merely shifting traffic from one area to another.
Surya has also highlighted the absence of geological and environmental impact studies and accused the government of bypassing public consultation. He has urged the state to prioritise metro, suburban rail, and BMTC expansion rather than investing in what he calls a “vanity project.”
Lalbagh Row Reaches the High Court
The controversy has now reached the courts. Actor and activist Prakash Belawadi has filed a petition in the Karnataka High Court opposing any alienation of Lalbagh land for the tunnel project and demanding a geological impact survey before work proceeds.
During the hearing, the state government informed the court that no trees in Lalbagh would be cut for the twin-tube tunnel. A bench comprising Chief Justice Vibhu Bakhru and Justice CM Poonacha orally observed that the status quo should be maintained until the next hearing scheduled for December 9.
Belawadi’s petition, supported by advocate and MP Tejasvi Surya, raised concerns about the potential impact on 6.5 acres of Lalbagh land and the three-billion-year-old Lalbagh Rock formation. Senior advocate D.R. Ravishankar, representing Belawadi, told the court that “though it is a stillborn project on paper, they have already started the tendering process.”
Citizens Speak Out: “#SayNoToTunnelRoad” Trends
Public opposition to the tunnel project has been growing both online and on the streets. Over the weekend, citizens, environmental activists, and several public figures including actors Sudha Belawadi and Samyukta gathered near Lalbagh to protest the project.
The hashtag #SayNoToTunnelRoad has been trending across social media platforms, reflecting growing anger among citizens who believe the project undermines the city’s fragile ecological balance.
A viral post from a Bengaluru commuter captured the frustration of many residents: “And do note I have a car and have to travel from Peenya to Jayanagar for work. And still I prefer metro because of the traffic! I oppose the tunnel road. Let there be at least one garden in Bengaluru where we can take our children for a picnic.”
Another widely shared message read: “There are plenty of places in Bengaluru to build commercial complexes. But Lalbagh is our green heritage. Already the city has no proper sewage, no proper roads, and an incomplete metro. What are they trying to do?”
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Signature Campaign to ‘Save Lalbagh’
Senior BJP leaders, including Leader of Opposition R Ashoka, MLC Gopinath Reddy, Bengaluru South District President and MLA CK Ramamurthy, and other party members, joined citizens at Lalbagh to protest the state government’s proposed Tunnel Road project and the acquisition of land within the botanical garden.
During the protest, the BJP Karnataka unit launched a signature campaign urging residents to participate in the movement to protect Lalbagh from land acquisition and potential commercial development. The campaign calls on Bengalureans to stand together in preserving one of the city’s most cherished green spaces.
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The Road Ahead
As public pressure mounts, all eyes are now on the High Court’s December hearing, which could determine the project’s immediate future. Meanwhile, the government and opposition continue to hold their ground, one presenting the tunnel as a vision for a modern Bengaluru, and the other condemning it as a reckless venture that could permanently scar the city’s heritage and environment.
Until the court’s decision, the Tunnel Road Project stands as a defining test of Bengaluru’s urban conscience, a debate between progress and preservation, speed and sustainability.