<p>The primary objective of this study aims to conduct a thorough reassessment of the hydrogeological conditions within the Nubian Sandstone Aquifer in the western desert, Egypt. This reassessment entails field hydrogeological and hydro-geochemical studies including pumping tests to ascertain the aquifer’s potentiality for optimal exploitation. Moreover, the study investigates the local water exploitation’s impact on both water level and to achieve the safe yield of the aquifer system, utilizing data obtained from 228 wells across the study area clarify that The depths of the wells vary significantly, ranging from 225&#xa0;m in El Kharga Oasis to 1502&#xa0;m in Siwa Oasis. This variation in depth reflects the geological heterogeneity of the aquifer system across different regions and also the potentiometric head is changed according to region from − 39.3&#xa0;m in the west to over + 150&#xa0;m in the north (above mean sea level), facilitating the construction of a potentiometric contour map. These maps reveal spatial variations in potentiometric head, which influenced by both geographical location and well depth, This demonstrates that variations in well depth and their regional distribution directly affect transmissivity values and aquifer performance. Furthermore, the observed changes in piezometric head from 1965 to the present highlight the aquifer’s sensitivity to long-term pumping stresses, underscoring the importance of forecasting future groundwater behavior for sustainable management. the analysis of pumping test data aids in clarifying the hydraulic parameters of the Nubian sandstone aquifer in the study region. By determining parameters transmissivity differs from 2791 m²/d in Baharyia to 1656 m²/d in Dakhla, and 682 m²/d, 1656 in Farafra, and finally 3137 m²/d in Siwa which means high potentiality in the northern part than the southern part of study area and this analysis provides valuable insights into the aquifer’s characteristics and potential for sustainable water resource management.</p>