EVALUATION OF WATER QUALITY OF SOME RIVERS IN DINAJPUR

Abstract

River water samples were collected from three rivers (Esamoti, Punarbhaba and Garbessary) of Dinajpur Sadar, Upazilla Dinajpur, Bangladesh during the months of August, December and April of the year 2014-2015 and analyzed for its quality and suitability for agricultural and aquatic purposes. Analyses were included pH, EC, temperature, dissolved oxygen (DO), alkalinity, cations (Ca2+ , Mg2+, Na+ and K+ ), anions (Cl- , HCO3 - , PO4 3- and SO4 2- ) and TDS (total Dissolved Solids) were done. Several variables such as SAR (Sodium Adsorption Ratio), SSP (Soluble Sodium Percentage) and hardness were also computed. Overall we found that the river water were acidic in nature (pH varied from 5.3 to 7.1) and could be suitable for agricultural and aquatic uses. River water samples contained Ca2+, Mg2+ and Na+ as the dominant cations and HCO3 - and Cl- were the dominant anions. According to TDS and SAR value, all samples were classed as “fresh water” and “excellent” categories. The soluble sodium percentage (SSP) of all water was under ‘excellent’ and 'good' classes. All samples were within 'soft' class regarding hardness. Based on SO4 2- , Cland PO4 3- all river water samples were within the 'safe' limit for irrigation. The DO concentration was suitable for fish production but more DO level should be present for all aquatic life especially for fish production