In the Issen irrigated perimeter of the Souss‐Massa Plain, Morocco, under a semi‐arid climate, the use of irrigation is inevitable for most crops. Therefore, groundwater is increasingly being used. Hydrochemical and statistical studies were conducted; they were carried out on the major and secondary elements of water (EC, Ca2+, pH, Mg2+, Na+, K+, Cl‐, SO42‐, HCO3‐, CO32‐, SAR and turbidity). The sampling period lasted over 2 years (2013 and 2014) spread over 3 seasons. The 36 wells that were analysed were spread across the studied plain. The values recorded during the sampling period showed that 11% of the analysed wells are highly saline in which EC > 3 dS m−1. Chemical analysis revealed a wide variety of chemical composition; samples are divided between two facies: sulphated magnesium calcium bicarbonate and sodium chloride. Then, statistical analyses of the studied parameters showed great variability and the results of analysis allowed maps of salinity and the SAR risk of irrigation water to be drawn. Copyright © 2018 John Wiley & Sons, Ltd.