Ground Water Year Book, 2019-2020: North Eastern Region

Ground water is a dynamic and replenishable resource and monitoring spatial and temporal changes of this resource is essential for sustainable development and management. The water level data is of paramount importance in development and management of water resources in the country. Central Ground Water Board decided to issue a Ground Water Year Book annually for each State by compiling the hydro-geological, hydro- chemical and water level data collected from the Ground Water Monitoring Stations (GWMS) established by the Board in the States. CGWB, NER has a permanent network of 624 GWMSs in North Eastern Region covering the States of Arunachal Pradesh, Assam, Manipur, Meghalaya, Nagaland and Tripura. Monitoring of water level and chemical quality furnish valuable information on the ground water regime, characteristics of the different hydro-geological units in the States, viz. the pattern of ground water movement, changes in recharge-discharge relationship, behaviour of water level and changes in quantity of ground water in space and time. It also helps in identifying and delineating water logged areas, possible ground water pollution hazards and areas prone to lowering of water table/piezometric surface due to large scale withdrawal of ground water. The behaviour of ground water level monitored from existing GWMSs and the chemical quality of ground water along with maps depicting the ground water scenario for the periods of measurement are presented in this report.