Isotope Hydrology in India

In the past few decades, sophisticated nuclear hydrological instruments have been developed to measure accurately both stable and radioactive isotopes. Due to the availability of such measurement facilities, many isotope techniques have been evolved and a large number of hydrological studies have been carried out world over using isotope techniques. In this paper, hydrological studies carried out in India using isotopic techniques have been reviewed and are grouped under four categories: (a) surface water studies that includes surface water-groundwater interaction, interconnection between water bodies, lake studies, sedimentation, seepage/leakage, discharge measurement, sediment transport, surface water pollution; (b) ground water studies that includes direct recharge to groundwater using natural and artificial isotope tracers, identification of recharge sources and zones, groundwater dating, soil moisture variation and recharge to groundwater, groundwater salinity, groundwater pollution, geothermal waters, aquifer-aquifer interconnection, (c) basic data generation including basic research in isotope hydrology; and (d) climate changes.