INVESTIGATION OF GROUNDWATER QUALITY AND ITS SUITABILITY FOR DRINKING AND AGRICULTURAL USE IN DINAJPUR SADAR UPAZILLA OF BANGLADESH

Abstract

For the assessment of the suitability of groundwater for drinking and irrigation uses, a study was conducted to examine the ionic concentrations of groundwater of the Sadar Upazilla in the District of Dinajpur, Bangladesh. Ten Water samples were collected from 10 hand tubewells from 10 different places and analyzed for p H , EC, cations (Ca2+ , Mg2+, Na+ , K+ , S+ and Zn2+ ), anions (HCO3 - , Pand Cl- ),TDS,SAR, SSP, Hardness, permeability index, Gibb‟s ratio and Kelly‟s ratio. The p H value (6.30 to 6.90) indicated that the waters were slightly acidic in nature. All water samples were under „very good‟, „good‟ and „permissible‟ categories according to Wilcox diagram. The content of Ca2+(15.76 to 33.39 mg /L), K + (0.22 to 3.10 mg/L), Na + (0.35 to 2.52 mg/L), Zn2+ (17.87 to 86.30 mg/L), Cl- ( 0.31 to 0.80 mg/L), revealed that all the samples considered in the present study were suitable for drinking and irrigation purpose. SAR and SSP are use to asses of irrigation suitability of water of all the samples were under „excellent‟ class. Kelley‟s ratio for the tested samples were under „good‟ classes that were suitable for irrigation purpose. PI of the tested samples were under classified as class II i.e, „good‟ that were suitable for irrigation purpose. According to TDS values, all samples were classed as „freshwater‟. Maximum samples were within „soft‟ class regarding hardness. According to EC values, the water samples were classified as Permissible. Gibbs diagram indicates that all the samples fall in the precipitation dominance field. Regarding cation and anion constituents, groundwater is suitable for irrigation and drinking purposes except of few wells.