Assessing Groundwater Depletion and Sustainable Water Management in Minna Metropolis, Nigeria: Implications for Sustainable Development Goal 6

Abstract

Groundwater depletion has emerged as a critical water management challenge in Minna Metropolis, Nigeria, driven by rapid urban growth, population increase, and persistent inadequacy of public water supply systems. Consequently, households and commercial users increasingly depend on groundwater abstraction through hand-dug wells and boreholes, placing sustained pressure on local aquifer systems. Although previous studies in Minna examined groundwater occurrence and quality, limited attention has been given to integrating household water demand, recharge estimation, and spatial hydrogeological controls into a unified framework for sustainable urban water management. This study adopted an integrated problem-solving approach to evaluate groundwater dependence and quantify the imbalance between abstraction and natural recharge. Geological and hydrogeological mapping, well inventory surveys, structured household water-use questionnaires, and a ten-year rainfall-based water balance analysis were employed. Groundwater was found to occur mainly within weathered and fractured basement formations, with a dominant NE-SW flow direction and identifiable recharge (Tudun Fulani, Maitunbi) and discharge (Kpakungu) zones. Household survey data indicated an average per capita water requirement of 62.5 L/day/person, translating to a total daily demand of approximately 15.5 million liters. In contrast, estimated natural recharge from rainfall infiltration was approximately 408,940 L/day. The results reveal a substantial demand-recharge imbalance of over 15 million liters per day, confirming unsustainable reliance under current abstraction patterns. Targeted management strategies, including recharge protection, artificial recharge, rainwater harvesting, demand-side conservation, and regulation of borehole development, are recommended to advance sustainable water governance and contribute to Sustainable Development Goal 6.

Keywords: groundwater depletion, sustainable water management, Sustainable Development Goal, recharge assessment, Minna metropolis