India is experiencing rapid urbanisation and escalating urban water demand. The city of Patna, located in the central part of the Gangetic plains, is one of the fastest growing metro cities in India. Despite the fact that Patna is located on the banks of the river Ganga, residents are dependent on only groundwater aquifers for domestic water supply. Increasing pressure on groundwater supplies is exacerbated by the unregulated construction of deep wells, along with the development of apartment complexes to accommodate a mushrooming urban population. A comparison of data sets from 1960 to 2010 shows deep aquifer declines (Saha et al. 2013). This raises concerns about Patna’s water supply security, its economic vitality and sustainability. Projected temperature increases will add to stress on water supplies, through increased water demand and evapotranspiration. The increasing exposure to climate change will be superimposed on existing vulnerabilities. In order to address these vulnerabilities and increase the Patna’s water security, the research recommends building the capacity of city water managers to use climate information in urban planning and development. According to our case studies of United States urban water management practices, consideration of long-term climate variations are key to informing sustainable water planning. One simple adaptation measure is to foster the sharing of climate information and data with water managers. The study concludes that these rudimentary measures to address Patna’s non-environmental water management challenges are a necessary stepping-stone to transformative pathways for dealing with climate change risks.