Climate Variability and Industrial Groundwater Abstraction in a Water-Stressed Petroleum Basin: Water Demand Dynamics in Lokichar Oil Production Wells, Kenya

The Lokichar Basin in Turkana, northern Kenya, is a semi-arid environment marked by pronounced rainfall variability and intense competition for water resources among domestic, livestock, and oil-driven industrial demands. This study assesses long-term rainfall trends (1981–2024), aquifer characteristics, groundwater levels, and demand dynamics to evaluate resource sustainability under oilfield development. Rainfall analyses using the Rainfall Anomaly Index, Standardized Precipitation Index, and Mann-Kendall tests show marked interannual variability, with significant increases in annual and October–December rainfall and evidence of non-stationarity in seasonal precipitation. Pumping tests from 23 boreholes reveal heterogeneous transmissivity (4.17 × 10⁻⁶–6.00 × 10⁻³ m²/s) and specific yield (0.036–0.500), with high-yield zones concentrated in Nakukulas. Continuous monitoring indicates daily groundwater fluctuations linked to domestic abstraction, while simulations project extreme midday drawdowns exceeding 60 m under full-scale oil production. Estimated natural recharge (21.8–43.6 Mm³ yr⁻¹) falls short of 2022 industrial demand (~53.0 Mm³ yr⁻¹), exposing a recharge–demand deficit. These findings highlight the vulnerability of Lokichar aquifer to over-abstraction and emphasize the need for integrated management, regulated abstraction, enhanced monitoring, and climate-responsive planning to secure water resources and support sustainable petroleum development in this fragile semi-arid basin.