Assessment of Groundwater Level and Fluctuations Using Geospatial Techniques in Nambiyar Watershed, South India

The discharge of groundwater sustains much of the flow in streams and the water in lakes and wetlands, especially during dry periods. Groundwater systems are dynamic and constantly adapt to changes in climate, groundwater withdrawal, and land use, both in short and long term. Long-term measurement is useful for identifying any significant water-level deviation from the mean, as well as the rates of increase and decrease over decades from the initial static water level, forecasts future water levels. Rainfall alone is not a reliable indicator of groundwater level change. If annual withdrawals are constant, recharge is a governing factor.