Assessment of groundwater pollution using PIG index and microbiological indicators in the Angads plain, Morocco

Abstract

This study assessed the hydrochemical quality of groundwater in the Angads plain using the pollution index of groundwater (PIG), and microbiological indicators. Two sampling campaigns were carried out in 2023 (wet and dry seasons), with 45 samples taken each year. The analyses revealed that the majority of the ions studied exceeded the limits recommended and authorized by the World Health Organization (WHO). The PIG revealed that over 80% of samples fall into the insignificant and low pollution categories, with pollution levels increasing during the dry season. Microbiological analyses revealed the presence of fecal coliforms (FC), total coliforms (TC), intestinal enterococci (IE) and sulfate-reducing clostridium (SRC) with average levels of 52, 80, 2, and 0 CFU/100 mL during the wet season, while during the dry season these values increased to 79, 120, 3, and 0 CFU/100 mL, respectively. This study offers vital information on groundwater pollution, enabling decision makers, residents, and scientists to better identify safe water sources and areas at risk. The findings highlight the urgency of implementing effective treatment solutions and devising sustainable management plans to preserve these water resources over the long term.