Hydrogeochemical Characterization And Evaluation Of Surface And Shallow Groundwater Quality In Talata-Mafara For Irrigation Purposes, Northwestern Nigeria

A combined hydrogeochemical and hydrogeological investigation was undertaken in Talata-Mafara to evaluate irrigation water quality and shallow groundwater’s potential for irrigation purposes. This assessment aimed to ascertain the suitability of surface and shallow groundwater for irrigation. The Piper diagram illustrates Na+–K+–Cl−–SO42− as the prevalent ions, with rock dominance identified as the primary factor influencing groundwater chemistry, as shown in Gibb’s diagram. Analysis of irrigation water quality indicates that most samples were rated as excellent or good in terms of salinity risk, SAR, RSC, magnesium risk, index of permeability, and salinity potential. However, many samples were doubtful regarding Percent Sodium and unsuitable in Kelly’s ratio. Eight Vertical Electrical Profile (VEP) points were collected in the study area, indicating a promising groundwater potential. The apparent resistivity values of the underlying lithology, consisting of clastic sedimentary rocks (sands and gravels) in the form of topsoil (0-20m), weathered/fractured basement (2.5-100m), and fresh basement rocks (>100m thick), supported this conclusion. The pumping test data collected from different boreholes supports the rocks’ conductivity. In most areas, the groundwater is quite shallow, around 9 metres deep, except in New Maradun, where some boreholes had negative yields and a static water level of about 50 metres. The groundwater flow in the area predominantly flows northwest. The region’s surface water and near-surface aquifers can be used for irrigation. Improving the drainage system within farmlands is necessary to mitigate the excessive buildup of dissolved ions in the crop root zone, which may escalate to hazardous levels.