Assessing Water Quality of a Rural Stream Southeast Nigeria for Irrigation Purpose

Aspects of the physicochemical parameters of a rural stream, in Southeast Nigeria, were evaluated for 12 months, between November 2021 and October 2022 in 3 stations in relation to suitability for irrigation purposes. Ten (10) physicochemical parameters were evaluated using standard methods and compared with the Food and Agriculture Organization (FAO) Irrigation Water Quality standard. Irrigation indices like Sodium Absorption Ratio (SAR), Percentage Sodium (%Na), Kelly’s Index (KI), Magnesium Hazard (MH), Soluble Sodium Percentage (SSP), Cation Ratio of Soil Structural Stability (CROSS), Permeability Index (PI), Potential Salinity (PS), Total Hardness (TH), and Residual Sodium Bicarbonate (RSBC) were also used for the irrigation suitability assessment. The physicochemical parameters were: pH (5.00–8.60), total dissolved solids (9.00–75.00 mg l-1), electrical conductivity (18.00–150.00µS cm-1), bicarbonate (22.70–91.50 mg l-1), chloride (17.00–195.00 mg l-1), sulphate (0.01–0.76 mg l-1), magnesium (0.26–3.71 mg l-1), sodium (0.11–1.18 mg l-1), potassium (0.05–0.98 mg l-1) and calcium (0.31–5.11 mg l-1). Spatially and seasonally, the mean values conformed to irrigation water standards except pH (dry season). All the parameters recorded higher values in station 1 and wet season (except Chloride). The irrigation indices were: SAR (0.10 – 0.14), %Na (15.0 – 25.0), KI (0.12 – 0.25), MH (50.00 – 55.60), SSP (10.53 – 18.20), CROSS (0.10 – 0.20), PI (68.2 – 185.7), PS (1.92 – 2.71), TH (0.20 - 0.64), and RSBC (0.89 – 1.10). All indicated suitability except MH (all stations and wet season) and PI (wet season). Anthropogenic activities and seasons influenced the water quality of the stream and the indices. It can be concluded that the Azueke stream is suitable for irrigation.