Groundwater quality evaluation for domestic and irrigation purposes for the Nwanedi Agricultural Community, Limpopo Province, South Africa

In addition to quantity of water supply for various water uses, water quality is also of concern. The current state of the water quality is not known; neither is its suitability for domestic and agricultural uses. The current study investigated the suitability of the groundwater resource for domestic and agricultural uses in Nwanedi agricultural community. Water samples were collected from the existing boreholes following procedure for standard water sampling. Physicochemical parameters (pH, TDS, EC), anions (Cl-, SO42-, HCO3, and NO3--N), cations (Mg, Ca, K, and Na), and HCO3 were analysed successively. The assay results were used to generate the agricultural water quality parameters (Sodium Adsorption Ratio, Magnesium Adsorption Ratio, Permeability Index, Residual Sodium Carbonates, Sodium percentage, Kelly's Ration and Chloride Index). Also, the communality test was conducted to investigate the suitability of the data for factor analysis and the loading of different parameters on the resultant factors. The assay results indicated that the water quality in the area is relatively fresh and adequate for domestic consumption, although there are infrequent excessive levels of nitrates ranging between 0.52-135.54 mg/l. Similarly, the groundwater was found to be ideal for irrigation (SAR 0.07-0.94 meq/l, MAR 26-48 meq/l, PI (92.5%) Class 1, PI 13-111 meq/l, RSC <-1, and CI 1/4 Class 1). The communalities which are the index of the measure of efficiency indicated that all the parameters except K were suitable for FA assessment. The hydro-chemical composition is controlled by natural and anthropogenic processes such as on-sight sanitation, agricul-tural leachates, and domestic effluents. Future comparative studies on how groundwater quality is influenced by climate conditions (dry and wet season) should be conducted in this area.

Automated summary

This study investigated the suitability of groundwater for domestic and agricultural uses in Nwanedi agricultural community. The results showed that the water quality is suitable for consumption and irrigation, with occasional excessive levels of nitrates. Factor analysis demonstrated the suitability of water quality parameters. Natural and anthropogenic processes influence the hydro-chemical composition. Future comparative studies on the influence of climate conditions are recommended.