International Journal of Research and Development in Engineering Sciences https://www.ijrdes.com D. Vijay Kumar 3 3 (May - June) 2021 05 May-June enGroundwaterHydrogeologyInvestigation methodsWater resourcesIndia Groundwater is a vital natural resource in India serving as a primary source of drinking water irrigation and industrial use With the growing population and agricultural demands groundwater depletion and contamination have become pressing environmental challenges This paper presents a comprehensive study on groundwater sources their distribution and methods of investigation in India It explores hydrogeological characteristics aquifer types and regional variations in groundwater availability across different climatic and geological zones Various investigation techniques such as geophysical surveys remote sensing GIS mapping and groundwater quality analysis are discussed for assessing resource potential and sustainability The study also examines issues of overextraction pollution from agricultural runoff and industrial effluents and the impact of climate change on groundwater recharge Policy measures and management strategies implemented under national programs like the Atal Bhujal Yojana are reviewed The paper concludes that integrating scientific investigation with sustainable management practices is essential for conserving Indias groundwater resources and ensuring longterm water security Copyright (c) 2026 International Journal of Research and Development in Engineering Sciences. All rights reserved. 2021 All Rights Reserved