Seasonal water quality monitoring of the Bhairab River at Noapara industrial area in Bangladesh

Abstract

The Bhairab River is located in south-western part of Bangladesh which is acting as a source of irrigation, drinking, industrial process water and also sinks for waste water. This study area is stands on this river which is situated at Noapara municipality under Abhaynagar upazila of Jessore district in Bangladesh. This river receives wastewater from various sources along its way which are discharging as industrial effluents, municipal sewage, household waste, clinical waste and oils. It was monitored the seasonal variability of surface water quality and impact of waste water on river which is provide an updated report on present status of the Bhairab River. Water samples were collected in the year 2016–2017 during winter, summer and rainy seasons from six different sampling stations. It was measured arsenic, iron, manganese, lead, chromium and cadmium by HG-AAS and flame-AAS methods respectively. Water quality index was calculated from five parameters at each sampling stations in three seasons individually. Average concentrations of metals in three seasons were compared with DoE standard for inland surface water in Bangladesh. This study is indicated that water quality was relatively good in rainy season due to huge discharge volume of fresh water and less effect of tidal flow. The seasonal pollution load index order was summer > winter > rainy season respectively. Critical condition of water quality observed in summer season due to low discharge volume fresh water, effect of tidal flow and waste water runoff from densely populated catchment.