Temporal Variation of Physical and Chemical Characteristics of Water in Buriganga River

The study was performed to evaluate the water quality of Buriganga River in the context of physical and chemical properties for winter (February), summer (May) and rainy (August) season between the periods of 2010- 2020 based on available published information. In-situ water quality parameters such as Temperature, Total Dissolved Solids (TDS), Electrical Conductivity (EC), pH and Dissolved Oxygen (DO) were determined at some selected locations (Mirpur Bridge, Hazaribag, Kamrangir Char, Chandnighat, Sadarghat, Dholaikhal, BD-China Friendship Bridge and Pagla) during winter (February) season, 2020. Weighted Arithmetic Water Quality Index (WAWQI) was used to calculate the water quality status of the Buriganga River. Study findings suggested that, DO concentration of water of Buriganga River was very low particularly in winter season. Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and turbidity concentration crossed the maximum permissible limit during winter (February) and rainy (August) seasons according to recommended standard of inland surface water of the Department of Environment (DoE), Bangladesh. The sequence of the WQI from 2010 to 2020 was 2011>2016>2017>2019>2010>2015>2017>2018>2012>2013>2020 in the winter (February) season whereas in the summer (May) and rainy (August), season the order were 2012>2011>2010>2013>2018>2016>2014>2019>2015>2017 and 2011> 2012> 2010> 2016> 2014> 2015> 2013>2017>2019>2018, respectively. The obtained results also indicate that, water of the Buriganga River is extremely polluted in winter (February) and rainy (August) seasons and it was unsuitable for drinking and fisheries purposes. The implication of these findings can be used to monitor health of riverine ecosystems which provide ecosystem services for society.