Spatial and Temporal Variations in Ganga River Water Quality: Insights from GIS Analysis (2017–2021)

The Ganga River serves as a vital source of fresh water and holds significant cultural and religious value in India, however, pollution has severely degraded the water quality, posing threats to human health and ecological integrity. This study analyzes water quality trends in the Ganga River from 2017 to 2021, focusing on Uttar Pradesh, India, and evaluates the impact of the COVID-19 pandemic on water quality parameters. Results indicated maximum fluctuations in temperature, dissolved oxygen, pH, biochemical oxygen demand (BOD), and nitrate levels were reported 29.5-34ºc, 11–12.5 mg/L, 8.6–9, 560–2200 (µmho/cm), 5.3–9.8 mg/L, 1.83–9.4 (mg/L) influenced by anthropogenic activities and natural environmental dynamics. The correlation analysis highlights significant relationships among water quality parameters. Strong significant positive correlations were observed between pH with fecal coliform (0.73) and total coliform (0.80), whereas a strong negative correlation was calculated between DO with fecal coliform (-.83) and total coliform (0.90). In addition, spatial analysis using GIS underscores the heterogeneous distribution of water quality parameters across the Ganga River basin, emphasizing more pollutant loads downstream which needs targeted interventions to mitigate pollution sources and ensure sustainable water management practices. This study contributes to bridging the existing knowledge gap regarding the dynamic evolution of water quality in the Ganga River, facilitating informed decision-making for policy formulation and implementation to safeguard water resources for future generations.