Water quality assessment of river Ganga in downstream area to Kanpur city

Abstract

The sacred river Ganga in Kanpur city, Uttar Pradesh, India, underwent physio- chemical analysis in the month of Nov 2022. Three samples from each of the ten locations in Kanpur city were collected over two days and analyzed various physicochemical parameters: temperature, pH, total alkalinity (TA), biological oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO), total dissolved solids (TDS), chlorides, electric conductivity (EC), nitrate, and total hardness (TH). Pearson correlation analysis was conducted in SPSS to examine relationships between these parameters. The investigation highlights significant trends in water quality parameters along different sites. The Bithoor site exhibited better DO levels (7.32 mg L-1) and a slightly alkaline pH (8.31), indicating relatively healthier water conditions. In contrast, the Sarsaiya ghat site maintained stable BOD (22.25 mg L-1), chloride levels (16.99 mg L-1), and alkalinity (450.15 mg L-1), suggesting a more buffered but still impacted ecosystem. The Jajmau site showed the highest levels of BOD (38.78 mg L-1) and TDS (270.78 mg L-1), coupled with an elevated pH of 8.67 and chloride concentration of 21.12 mg L-1, pointing to higher organic pollution and industrial effluents. A notable negative correlation was observed between DO and other water quality parameters, reinforcing the trend of declining oxygen levels with increasing pollution. Conversely, pH, temperature, COD, BOD, TA, TH, TDS, chloride (Cl-), EC, sulfate (So₄ ²-), and nitrate (No₃ -) exhibited positive correlations, demonstrating a progressive deterioration of water quality from upstream to downstream. The Ganga river's water quality needs to be routinely checked to conduct appropriate treatment. The findings hold critical relevance for environmental policymakers, offering evidence-based insights for the development of sustainable water resource management strategies. Addressing the pollution of the Ganga is essential to restore its sanctity and safeguard public health, support aquatic ecosystems, and ensure long-term socio-economic sustainability.