Urban Floods: A Case Study of Patna Floods 2019 – Natural or Anthropogenic?

In September 2019, Patna witnessed an urban flood due to a greater than expected rainfall. Nearly 177 mm of precipitation within 48 h broke the decade-old record of 158 mm on September 3, 2013. This was also the highest rainfall recorded in September at nearly 430 mm, eclipsing the old record of 400 mm. Five teams of NDRF were deployed in the city, which rescued nearly 5000 people from the flood-affected areas. The floods led to the loss of property, damaged structures, and the spread of waterborne diseases. In the 6 years (i.e., from 2013 to 2019), what had changed in Patna city that a rise of nearly 12% in highest rainfall during September led to such an extent of flooding? Though the deluge was immediately blamed on climate change, it cannot be understated how unplanned rapid urbanization, deforestation, exploitation of flood plain, and lack of proper drainage networks are the underlying factors which aggravate the impact of climate change. Lack of flood zoning, lack of proper action plan for disaster management, and lack of proper legislation add fuel to the fire in terms of preparedness. This case study aims to explore the different natural and anthropogenic factors which congregated to cause the Patna flood of 2019 so that appropriate mitigation strategies can be worked out and implemented to abate future urban floods in Patna.