Bengaluru: In a setback to the Karnataka government and Deputy Chief Minister D.K. Shivakumar’s ambitious Bengaluru tunnel road project, an expert committee appointed by the Urban Development Department (UDD) has raised serious concerns over the quality and methodology of the Detailed Project Report (DPR) prepared for the proposed underground corridor.
The committee, led by Siddanagouda Hegaraddi, Executive Director (Civil) of Bangalore Metro Rail Corporation Limited (BMRCL), observed that the DPR appeared to have been prepared “in a hurry” and based on only four soil test points, which it deemed “far too few for a project of this magnitude.”
Committee questions project preparedness
The expert panel’s findings, submitted recently to the Urban Development Department, pointed to several technical and environmental lapses in the DPR. The report states that reliance on limited geotechnical data could pose significant risks during tunnelling, particularly in Bengaluru’s diverse sub-surface conditions that vary between granite, clay, and silt layers.
“For a project that proposes to run several kilometres underground, four boreholes cannot provide a reliable representation of soil and rock strata. This poses potential design and safety challenges,” the committee noted.
Officials familiar with the review said that the panel has advised the government to conduct a comprehensive geotechnical investigation and independent validation of the DPR before moving forward.
Environmental concerns over Lalbagh
The committee also flagged environmental risks associated with the proposed tunnel alignment, which reportedly involves constructing one of the tunnel shafts inside Lalbagh Botanical Garden, one of Bengaluru’s most prominent green spaces.
“Positioning one of the tunnel shafts within Lalbagh Botanical Garden needs to be re-examined because of environmental sensitivity,” the committee recommended.
Environmentalists have long opposed any construction activity within or near Lalbagh, which is home to hundreds of native and exotic plant species and serves as a vital carbon sink for the city. The expert panel’s endorsement of these concerns adds weight to calls for rethinking the alignment.
Traffic and pollution impact questioned
The panel’s report also cast doubts on the traffic impact analysis conducted for the project, observing that key data and modelling inputs were inadequate. The committee warned that the tunnel road might not alleviate congestion on major corridors such as the Outer Ring Road (ORR), and could, in fact, worsen vehicular pollution by encouraging more private vehicle usage.
“The tunnel road, while intended to ease traffic, could draw additional private vehicles rather than reducing them, leading to higher emissions and air quality deterioration,” the report stated.
It further highlighted that public transport efficiency could be undermined if investment and focus shift towards road-based infrastructure instead of mass transit systems.
Why a tunnel when the metro serves the same corridor?
One of the most striking findings in the expert committee’s review is the overlap between the tunnel’s proposed route and the Namma Metro’s planned north–south corridor. The committee observed that the tunnel alignment runs almost parallel to the upcoming metro line, raising questions about the project’s necessity and financial prudence.
“Without clear data on how many commuters will shift from private vehicles to metro or bus systems in the coming years, the justification for a parallel high-cost tunnel cannot be verified,” the report noted.
Experts said this overlap could lead to duplicated infrastructure, redundant expenditure, and underutilisation of public transport investments, especially as metro expansion continues across Bengaluru.
D.K. Shivakumar’s vision faces fresh scrutiny
Deputy Chief Minister D.K. Shivakumar has championed the tunnel road as part of a broader plan to decongest Bengaluru and modernise its traffic infrastructure. The project, initially proposed to span over 50 kilometres across the city’s core areas, was envisioned as an alternative to elevated corridors that had faced widespread opposition.
However, the latest review by the expert committee has cast a shadow over the project’s feasibility. The government is now expected to revisit the DPR and possibly revise the alignment, cost estimates, and environmental strategy before proceeding to the next stage.
Conclusion
The expert committee’s findings underline a need for greater transparency, data-backed planning, and environmental caution in Bengaluru’s urban infrastructure projects. With the tunnel road proposal now facing multiple red flags — from inadequate soil testing to environmental and transport overlaps — the state government will have to weigh its next steps carefully.
As Bengaluru continues to grapple with chronic traffic congestion, experts suggest that prioritising metro expansion, bus modernisation, and last-mile connectivity could offer more sustainable long-term solutions than expensive road tunnels.