Assessing Hydroclimatic Drivers of Groundwater Fluctuations through IoT-based Real-Time Monitoring

Abstract

To better understand recharge processes, groundwater depletion in semi-arid regions experiencing increasing development needs ongoing monitoring. This study examines the role of hydroclimatic factors in regulating groundwater level variations on a short timescale and assesses the efficacy of a low-cost Internet of Things (IoT) network for groundwater level monitoring in a managed aquifer recharge (MAR) well in Islamabad, Pakistan. Strong agreement (R² = 0.998) was found when the system was calibrated and validated in the lab against a commercial water level data recorder. In addition to satellite-based meteorological data, daily data from December 2023 to April 2024 contained temperature, total dissolved solids (TDS), and groundwater level. The analysis of the data reveals that atmospheric demand primarily regulates the groundwater system, particularly during the dry season. This is demonstrated by the positive correlations between groundwater level and air temperature (r = 0.68) and ET0 (r = 0.70), whereas precipitation is a response with a lag. Simplified groundwater balance models are inadequate, as evidenced by the weekly water balance's only 2% variability. The need for thorough water quality monitoring is highlighted by the high total dissolved solids (TDS) concentration values (2,300–3,900 mg/L). The study proves the effectiveness of IoT-based systems for real-time MAR performance evaluation in data-poor urban areas.