TUNNEL VISION

Bengaluru's civic body must ascertain suitability of the city's geology before moving ahead with its tunnel road project for seamless travel

- G V HEGDE AND K C SUBHASH CHANDRA

With over 15 million vehicles plying the roads of Bengaluru, the rapidly expanding megacity no doubt grapples with severe traffic congestion despite the expansion of public transport facilities like the metro-rail services. The 2024 congestion level index by TomTom, a Dutch location technology developer, says Bengaluru is the third-slowest city for traffic in the world, behind only Barranquilla in Colombia and Kolkata. So to decongest the Silicon Valley of India and ensure a “seamless travel solution”, the city’s civic body, Bruhat Bengaluru Mahanagara Palike (BBMP), has unveiled the blueprint of an ambitious public infrastructure plan that involves constructing elevated corridors, under-passes and even tunnel roads between key corridors, such as Hebbal Esteem Mall junction and Silk Road KSRP junction. A New Delhi-based consultancy firm has submitted its feasibility report for the project to BBMP in December 2024.

However, a quick analysis of the feasibility report shows that not much emphasis has been placed on the ground-truth data related to the region’s lithology (which explains the characteristics of rocks) and hydrogeology (movement of groundwater and how it interacts with soil and rocks). Such data is particularly necessary to assess the viability of tunnelling projects that are influenced by the geological condition of the region and may lead to hazards such as subsidence and landslides. It is also important because of the city's complex geology.