Physicochemical Parameters of West Banas Dam and Selwada Dam, Sirohi District, Rajasthan, India, in 2022–2024

Abstract

Aims: This study measured and compared ten physicochemical parameters and water colour in West Banas Dam (WBD) and Selwada Dam (SWD), Sirohi district, Rajasthan, across summer, monsoon and winter from 2022 to 2024. Study Design: Repeated seasonal field sampling was conducted at three stations in each dam, with three replicate samples per station. The dams were compared using a paired t-test, and seasons were compared using one-way analysis of variance. Place and Duration of Study: West Banas Dam and Selwada Dam, Sirohi district, Rajasthan, India, from summer 2022 to winter 2024, comprising nine sampling campaigns. Methodology: Water temperature, pH, electrical conductivity, total dissolved solids, turbidity, dissolved oxygen, biochemical oxygen demand, free carbon dioxide, total alkalinity and total hardness were measured using standard methods. Water colour was also recorded. Results: West Banas Dam had higher electrical conductivity (mean 477.4 against 320.9 µS/cm, P < .001), total dissolved solids (330.1 against 233.4 mg/L, P = .01), biochemical oxygen demand (3.56 against 2.53 mg/L, P < .001), free carbon dioxide, alkalinity, hardness and pH than Selwada Dam. Its dissolved oxygen was lower (7.32 against 7.97 mg/L, P < .001). Temperature (P = .16) and turbidity (P = .12) did not differ between the dams. In both dams, most chemical parameters were highest in summer. Turbidity was highest in the monsoon, and dissolved oxygen was highest in winter. Dissolved oxygen did not fall below 5.9 mg/L in any campaign. Conclusion: West Banas Dam had a higher ionic and organic load than Selwada Dam, while both dams remained well oxygenated. The data provide reference values for future monitoring of these two reservoirs.