Suitability Assessment of Groundwater Quality in Sidi Allal Tazi Region Using Water Quality Index

Abstract

Groundwater plays a vital role as a natural resource essential for supporting life. This study aimed to evaluate the suitability of groundwater for drinking purposes in the Sidi Alall Tazi region, Morocco, using water quality indices (WQI). Forty-five water samples were collected from different locations in the study area. The investigation focused on the spatial and temporal variations of physical parameters, such as pH, and electrical conductivity (EC), and chemical parameters, such as sodium (Na + ), magnesium (Mg 2+ ), nitrate (NO3 -), chloride (Cl -), potassium (K + ), calcium (Ca 2+ ), and bicarbonate (HCO3 -). The spatial distribution of Ca 2+ , EC, and Na + revealed poor groundwater quality in some wells located near the Nador Canal and the Esbou River. The spatial distribution of nitrates (NO3 -) was higher than the permissible limit in most of the study samples due to the excessive use of agricultural fertilizers in the study area. The results of WQI values ranged from 54.4 to 341. Specifically, samples W33 and W35 were found to be unsuitable for drinking purposes, with WQI values of 341.9 and 317.4, respectively, indicating poor water quality attributed to factors such as river intrusion, overexploitation, and harsh weather conditions. It is worth noting that the majority of the parameter values exceeded the recommended limits set by the World Health Organization (WHO) for safe consumption. By analyzing groundwater quality data and mapping the distribution of pollutants, officials can take measures to mitigate and prevent further pollution.