Dr Mukherjee has made significant contributions to interdisciplinary, field and laboratory-based numerical studies to understand the decadal-scale changes in groundwater quantity and quality in India. This work of social relevance quantified geological and human influences on groundwater chemistry, elucidated manmade and geo-genic pollutants and measured groundwater-sea water interactions in two major river basins. He has provided estimates on groundwater-sourced drinking water availability across India, and his studies have informed national water missions and policies.