Seasonal Water Quality Assessment of Ode Lake: A Two-Year Analysis of Physico-Chemical Parameters and Pollution Load

Abstract: Climate change, population growth, and anthropogenic pollution have intensified water depletion and contamination, making water scarcity a critical global issue. Periodic assessment of freshwater quality is essential for developing protection strategies. In this study, the water quality of Ode Lake, Ahmedabad, Gujarat, was evaluated over two years (Feb 2022 – Oct 2023) using 19 physico-chemical parameters to assess potability and usability. The following water parameters were analyzed in the study to check pollution load on freshwater source – Temp, pH, EC, DO, BOD, COD, Ca, Cl, F, Mg, Na, NH3, NO3, SO4, TA, TDS, TH, TSS, TC. Samples were collected seasonally from February 2022 to October 2023. Laboratory analysis of sample was performed using methods mentioned by IS:3025 and APHA. Results obtained were statistically analyzed to understand characteristics of each parameter of the water body. Pearson correlation matrix was obtained, BISWQI was calculated, and water was classified for each season. Suitability of water for various purposes were determined using CPCB’s ‘Designated Best Use’ guideline. Most of the parameters were within the standard limit set by BIS & WHO. The mean BISWQI of Ode Lake is 90 (SD = 18.9) and Ode Lake water is categorized as ‘Good’. Although water quality being ‘Good’, visible evidence of pollution was found and as per DBU guideline by CPCB, the water is usable for the purpose of irrigation and fisheries. Due to high levels of coliform, BOD and COD, organic pollution in the lake is evident, mainly caused by sewage input and waste disposal. Use of water for drinking purposes without adequate treatment must be avoided due to high coliform levels.