Quantitative Assessment of Groundwater Over-Exploitation and Recharge Sensitivity in Delhi, India: A Case Study of Delhi, India

Abstract

Groundwater overexploitation in the National Capital Territory (NCT) of Delhi has reached critical levels, with annual
extraction (~480 MCM) exceeding net recharge (~290 MCM) yielding an overall Stage of Extraction of 165% declining
1–2 m/year in South and Southwest Delhi. This study aims to quantify the recharge–draft imbalance across the National Capital Territory (NCT) and assess the sensitivity of groundwater availability to key hydrological parameters. Groundwater levels from Central Ground Water Board) CGWB, water-supply records from DJB, rainfall data, and land-use information were integrated into a Groundwater Estimate Committee (GEC)-2015 based groundwater balance model. Recharge and draft were computed for all districts, and sensitivity analysis was conducted using ±30 percent recharge and ±20 percent draft variability. Spatial assessment was performed using GIS to identify over-exploited aquifers and potential recharge zones. Results indicate that the city’s overall Stage of Extraction (SOE) is approximately 165 percent, confirming severe over-exploitation. Recharge variability exerts the strongest influence on groundwater balance, with a ±30 percent change shifting the SOE by nearly ±22 percent. South, Southwest, and New Delhi emerge as the most critical zones, while the Yamuna floodplain shows significant recharge potential. Enhancing recharge by 25–30 percent could reduce the SOE to near-sustainable levels (~110 percent). The study provides a robust, evidence-based framework to support Managed Aquifer Recharge interventions and policy decisions under Delhi’s Master Plan 2041.