GROUNDWATER MINERALIZATION AND ITS IMPLICATIONS FOR DOMESTIC AND IRRIGATION PURPOSES IN TOLON DISTRICT, GHANA

Abstract

Groundwater resources play a crucial role in sustaining the livelihoods of inhabitants in the semi arid Tolon District of the Northern Region of Ghana. This study assessed access to drinking water resources in relation to socioeconomic and geographical factors, investigated the sources and mechanisms of groundwater mineralization, evaluated groundwater quality for domestic and irrigation purposes, and assessed the associated human health risks. Ninety-seven (97) groundwater samples were analyzed using a combination of multivariate statistical, geostatistical, and geochemical techniques. Irrigation Water Quality Indices (IWQIs) were applied to determine groundwater suitability for irrigation. The results showed that only 40% of households had access to improved drinking water sources, with about 85% of the population consuming less than 15 liters of water per person per day. Access to drinking water varied significantly across socioeconomic groups and geographical locations. Hydrochemical analysis identified EC, TDS, Na⁺, Mg²⁺, HCO₃⁻, and Cl⁻ as the major contributors to groundwater mineralization, with dominant water types being Na–HCO₃, Na–Cl, Ca–HCO₃, and Mg–HCO₃. Evaporation and anthropogenic activities, particularly agriculture, were found to be the main sources of groundwater contamination. Water quality assessment revealed that several parameters, including turbidity, EC, Ca²⁺, F⁻, NO₃⁻, As, Cd, faecal coliforms (FC), and total coliforms (TC), exceeded the WHO recommended limits. The Water Quality Index (WQI) indicated that 1.82% and 2.38% of groundwater samples were unsuitable for drinking during the rainy and dry seasons, respectively. Health risk assessment identified non-carcinogenic risks associated with NO₃⁻, F⁻, As, and Cd, while carcinogenic risks from As and Cd were notably higher among children. Groundwater suitability for irrigation varied spatially and seasonally, with the southeastern parts of the district exhibiting higher mineralization and generally poorer water quality. In conclusion, the study highlights significant challenges in ensuring groundwater safety for both domestic and agricultural uses. The findings underscore the urgent need for continuous monitoring, improved groundwater management, and the implementation of mitigation measures to safeguard public health and promote sustainable water use in the Tolon District.