A Study of Urban Flooding in the Patna Municipal Corporation Area: Causes, Vulnerability Assessment, and Mitigation Strategies

A Study of Urban Flooding in the Patna Municipal Corporation Area: Causes, Vulnerability Assessment, and Mitigation Strategies Vishal Kumar* Patna, the capital of Bihar and seat of the Patna Municipal Corporation (PMC), is among the most flood-prone state capitals in India, threatened simultaneously by riverine flooding from the Ganga, Punpun and Sone rivers and by pluvial, drainage-congestion-driven urban flooding. The catastrophic waterlogging event of September 2019, in which the city received nearly 430 mm of rainfall in a single month and remained inundated for several days, exposed the compounding effects of rapid unplanned urbanisation, encroachment on natural drainage channels and low-lying depressions, an aging and poorly maintained sewerage network, and inadequate pumping infrastructure. This paper synthesises the physical, hydrological and institutional dimensions of flood risk within the PMC jurisdiction. It reviews the geomorphological setting of the city, evaluates the principal natural and anthropogenic drivers of flooding, and outlines a Geographic Information System (GIS) and remote-sensing-based framework — integrating Digital Elevation Model (DEM) derived slope and drainage density, land-use/land-cover change, rainfall intensity, and population density — for delineating flood-vulnerability zones across PMC wards. Findings from the literature indicate that low-lying south-eastern and north-western pockets of Patna district fall in the very-high vulnerability category, coinciding with areas of high population density and deficient stormwater infrastructure. The paper concludes with an integrated set of structural and non-structural mitigation measures — including drainage network rehabilitation, restoration of natural water bodies, ward-level early-warning systems, and land-use zoning reform — intended to inform municipal flood-management policy and to serve as a methodological foundation for further doctoral research on urban flood resilience in Patna. *Department of Geography, Central University of South Bihar, Gaya, India, Email: [email protected]