Assessment of water quality of groundwater, surface water, and wastewater using physicochemical parameters and microbiological indicators

ObjectiveWater quality plays a pivotal role in environmental health, with direct implications for ecosystems and human populations. This study offers a novel and comprehensive evaluation of four distinct water sources in northeastern Algeria raw wastewater (RWW), treated wastewater (TWW), Oued surface water (OSW) from Oued El Azzabi, and groundwater (GW) addressing a significant research gap in integrated water quality monitoring in semiarid regions. Unlike previous studies, this work integrates both physicochemical and microbiological indicators over a full annual cycle to assess the effectiveness of wastewater treatment and its environmental impact.MethodsA cross-sectional analysis was conducted using monthly samples collected from January 2023 to January 2024. Physicochemical parameters such as pH, turbidity, electrical conductivity, nutrients, and organic matter (5-day biological oxygen demand), along with microbiological indicators (total coliforms, fecal coliforms, fecal streptococci, sulfite-reducing clostridia, and aerobic mesophilic bacteria), were assessed. The water quality index (WQI) was used to synthesize the results and evaluate the overall water quality across sources.ResultsTWW met national and international standards, demonstrating the effectiveness of the Ain Beida treatment plant. In contrast, RWW showed high contamination levels, highlighting critical health risks. OSW displayed seasonal pollution patterns, especially during summer, due to runoff and human activities. GW exhibited relatively stable quality but indicated persistent low-level contamination. The WQI scores confirmed these findings, offering a comprehensive overview of spatial and temporal quality variations.ConclusionsThis study contributes valuable insights into water resource management in semiarid regions, emphasizing the importance of systematic monitoring and effective wastewater treatment. The results highlight the need for adaptive management strategies and underscore the potential of TWW as a safe alternative for agricultural or industrial reuse. These findings serve as a foundation for policy development and future research in similar ecological contexts.