Water scarcity is a serious concern in emerging economies, as it impacts human development, livelihoods, environment and economic growth. Policies should be formulated in a way that reflects the problem of water scarcity and is oriented towards providing solutions. The science–policy interface can play a key role in translating scientific knowledge into policy action and in mitigating water scarcity of emerging economies like that of India. Hence, the paper aims to review scientific knowledge on water scarcity in India, and analyze the extent to which this knowledge is reflected in the water policies – to understand the science–policy interface. This has been done by extensive review of various scientific approaches used to assess water scarcity at the national and state level. The analysis indicates that Punjab, Haryana, Rajasthan and Gujarat in the north-west, and Andhra Pradesh and Tamil Nadu in the south experience high water scarcity. To analyze whether this scientific knowledge has been translated into policy, existing water policies were critically reviewed. The paper, by identifying key policy areas, discusses challenges and opportunities for strengthening the science–policy interface, in the context of water scarcity mitigation. The paper argues that translating scientific knowledge into policy action continues to be a major challenge in India.