Assessment of river water quality for irrigation using multiple indices

The use of a single irrigation water index in the characterization of irrigation water quality may not suffice because of the combined and individual impact of several primary water physiochemical parameters on the overall water quality. Therefore, this study aimed to assess irrigation water quality using multiple indices. Surface water samples were taken from ten locations and analyzed using standard methods. The potential effects of the water quality on soil salinity, sodicity, and permeability hazards were assessed by using derived parameters including sodium adsorption ratio (SAR), soluble sodium percentage (SSP), permeability index (PI), Kelly's ratio, potential salinity (PS) and cation ratio of soil structural stability (CROSS)indices.SAR and CROSS values ranging from 1-1.93 and 0.86-1.36 respectively showed that all ten water samples had no sodicity hazard potential. KR and SSP, with values ranging from 0.66-1.58and 39.82-111.32 respectively, showedfour and eight samples were without sodicity hazard potentials, respectively.PS and Electrical conductivity assessed salinity hazard potential, while permeability hazard potential was assessed by the combinative indices of PI, SAR, and CROSS. Results of the indices showed that all ten river water samples were without permeability hazard potentials. However, with salinity hazards, EC and PS values which ranged between 128-552.38 S/cm and 0.52-0.84 showed that 90% and 100% of the river samples respectively were suitable for irrigation. Based on the results, using multiple indices is effective, but for sodicity hazard, the combinative use of SSP and KR should be accompanied by soil analysis