The Adani Group has emerged as the lowest financial bidder for both packages of Bengaluru’s proposed 16.75 km North–South underground tunnel road, according to reports.

Financial bids were opened by Bengaluru Smart Infrastructure Ltd (B-SMILE), the special purpose vehicle overseeing the project. Adani’s bids were significantly higher than the government’s initial estimates—around 24 per cent above projections for the first package and nearly 28 per cent higher for the second.

While the state government had estimated the total project cost at Rs 176.98 billion, Adani’s combined bid stands at approximately Rs 222.67 billion. The wide gap is expected to prompt the government to place the matter before the Karnataka Cabinet to determine the next course of action.

The tunnel road is proposed under the build-operate-transfer model, under which the government will fund 40 per cent of the project cost, with the remaining investment to be mobilised by the private concessionaire.

Four infrastructure companies had initially submitted bids for the project. However, only two—Adani Group and Hyderabad-based Vishwa Samudra Engineering Ltd—cleared the technical evaluation stage to reach the financial round. Dilip Buildcon was disqualified due to a tender condition barring firms linked to the collapse of major structures, while Rail Vikas Nigam Ltd exited after its joint venture partner failed to meet eligibility requirements. With Vishwa Samudra finishing second, Adani emerged as the lowest bidder.

The development marks a key milestone for the high-profile tunnel road, which has sparked intense political and civic debate. Several BJP leaders have opposed the project, particularly the proposed alignment that requires land from the historic Lalbagh Botanical Garden.

Urban mobility experts have also raised concerns that the underground corridor could overlap with and potentially undermine Metro Phase 3A, which runs close to the proposed tunnel route.

The tunnel road is a flagship initiative of the Congress-led Karnataka government and a key proposal of Deputy Chief Minister D K Shivakumar, who has argued that underground corridors are necessary to address Bengaluru’s immediate traffic congestion.

Critics, however, contend that car-centric infrastructure could divert resources away from mass public transport and induce higher traffic volumes over the long term.