Cities across the world are working with geoscientists to improve their understanding of the sub-surface in their urban planning. In India, what can be a better place than Varanasi, the oldest known city in India, to set the foundation of the ‘future city’? IIT Kharagpur in collaboration with the British Geological Survey is in the process of developing plans to undertake this gargantuan initiative. Three dimensional geological modelling of the geology under Varanasi will be prepared to help improve the building of new transport and service infrastructure, the preservation of archaeological sites, the management of flooding hazards and the sustainability of water supplies.
Investment in the challenges of urbanization is growing. But globally, few cities have a central database or planning system that incorporates the subsurface into the decision tree. Across India we are unaware of any examples, although in North America, Europe and other parts of Asia (e.g. Abu Dhabi, Glasgow, London, Manchester etc.) city planners are increasingly linked to consortia of national geological surveys and academic researchers to deliver improved planning decision and economic benefits through better understanding of ground conditions. The potential degradation of resources and environment affects both the city and its rural hinterland (catchment) but few studies consider them as a linked ecosystem, explained Prof. Abhijit Mukherjee, Project Leader from IIT Kharagpur’s Dept. of Geology and Geophysics. The project involves Prof. Probal Sengupta (Geology and Geophysics) and Prof. Joy Sen (Architecture and Regional Planning & RGCGSIDM) as co-Investigators.
Today, Varanasi is being re-designed as a future city with investment in infrastructure e.g. metro, new roads and bridges. Retro-fitting ancient cities like Varanasi to meet the rising demand for modern telecommunication and transport networks presents a challenge to the existing water supply and sewer infrastructure, the preservation of archaeological sites and sustaining a reliable water supply. Its future development will depend upon the sustainable use of natural (groundwater) resources, mitigation of flooding hazard and an understanding of the river dynamics and how these may evolve in response to future climate change. An understanding of the larger and smaller scale controls on past and present fluvial styles will enable prediction of how the system may evolve in the future.
The project includes application of geoscientific methods (e.g. drilling, geological, geophysical, tectonics, hydrogeological and remote sensing). It aims to delineate the evolution of Varanasi and other future of cities of India, from the hazard zonation/mitigation of the city. The retrieved information on rock and sediment lithologies, physical and chemical characteristics, geotechnical properties, hazard potential and groundwater distribution and flow will lead to construction of a multi-scale 3D conceptual model to allow visualisation of the ground beneath the city. It would be the first major 3D subsurface urban study and planning of its kind in India, with the ultimate aim of developing methodologies and input of suburban geology for planning and hazard risk assessment, , said Dr. Martin Smith, Director Science, British Geological Survey.
“The ultimate aim is to develop the methodologies and approaches of urban geosciences and engineering to urban geology at Varanasi as a pilot for other cities and to inform India’s Smart City mission” added Prof. Mukherjee.