Estimation of replenishable groundwater resources of India and their status of utilization

Dynamic groundwater resources of India have been estimated using groundwater resource estimation methodology-1997. The methodology uses the water-level fluctuation technique and empirical norms for recharge estimation. The groundwater utilization is also estimated. The stage of groundwater development is worked out and assessment units are categorized based on the stage of groundwater development and long-term water-level trend. The annual replenishable groundwater resources of India is 433 billion cubic metre (bcm) and net annual groundwater availability is 399 bcm. The annual groundwater draft for 2004 was 231 bcm. Thus the overall stage of groundwater development is 58%. Out of 5723 assessment units in the country, 4078 are 'safe' and 839 are 'over-exploited'. The rest fall under 'semi-critical' and 'critical' category. Over-exploitation is more prevalent in northwestern, western and Peninsular India. Eastern India has good potential for future groundwater development. Considering the changing groundwater scenario, re-assessment of groundwater resources needs to be carried out at regular intervals. This would require further strengthening of the available database.