The groundwater crisis in northwestern India is the result of over-exploitation of groundwater resources for irrigation. The Government of India has targeted a 20 percent improvement in irrigation groundwater use efficiency. In this perspective, and using a regional-scale calibrated and validated three-dimensional groundwater flow model, this article provides the first forecasts of water levels in the study area up to the year 2028, both with and without this improvement in use efficiency. Future water levels without any mitigation efforts are anticipated to decline by up to 2.8 m/year in some areas. A simulation with a 20 percent reduction in groundwater abstraction shows spatially varied aquifer responses. Tangible results are visible in a decade, and the water-level decline rates decrease by 36–67 percent in over-exploited areas. Although increasing irrigation use efficiency provides tangible benefits, an integrated approach to agricultural water management practice that incorporates use efficiency along with other measures like water-efficient cropping patterns and rainwater harvesting may yield better results in a shorter period.

The Indo‐Gangetic foreland basin has some of the highest rates of groundwater extraction in the world, focused in the states of Punjab and Haryana in northwest India. Any assessment of the effects of extraction on groundwater variation requires understanding of the geometry and sedimentary architecture of the alluvial aquifers, which in turn are set by their geomorphic and depositional setting. To assess the overall architecture of the aquifer system, we used satellite imagery and digital elevation models to map the geomorphology of the Sutlej and Yamuna fan systems, while aquifer geometry was assessed using 243 wells that extend to ∼200 m depth. Aquifers formed by sandy channel bodies in the subsurface of the Sutlej and Yamuna fans have a median thickness of 7 and 6 m, respectively, and follow heavy‐tailed thickness distributions. These distributions, along with evidence of persistence in aquifer fractions as determined from compensation analysis, indicate persistent reoccupation of channel positions and suggest that the major aquifers consist of stacked, multistoried channel bodies. The percentage of aquifer material in individual boreholes decreases down fan, although the exponent on the aquifer body thickness distribution remains similar, indicating that the total number of aquifer bodies decreases down fan but that individual bodies do not thin appreciably, particularly on the Yamuna fan. The interfan area and the fan marginal zone have thinner aquifers and a lower proportion of aquifer material, even in proximal locations. We conclude that geomorphic setting provides a first‐order control on the thickness, geometry, and stacking pattern of aquifer bodies across this critical region.

The Indian Summer Monsoon (ISM) characterizes the hydrometeorological variability across the north Indian region and contributes more than 75% of the annual rainfall during the monsoon (June–September) season. In the present study, we analysed the long-term monsoon rainfall for the Ganga River basin to investigate its spatio-temporal variability. A statistically increasing (10 to 17 mm/year; p < 0.05) trend has been observed in ISM rainfall for the mountainous region since 1980, accompanied by increased temperature. We further note that high, very high and extreme rainfall events are also increasing, enhancing the flash flood risk in the mountainous region. In contrast, the ISM rainfall in the alluvial region is observed to be statistically decreasing (−5 to −20 mm/year; p < 0.05) with the combined influence of reduced vegetation. These findings provide valuable insights into the variations in regional hydrology of the Ganga River basin caused by natural and anthropogenic factors.