ASSESSMENT OF SURFACE AND GROUNDWATER QUALITY OF DINAJPUR SADAR UNDER DINAJPUR DISTRICT

Abstract

Water samples were collected from different locations of Dinajpur sadar under Dinajpur district of Bangladesh and analyzed for quality assessment. Samples were collected from 16 surface and 24 groundwater. Analyses included pH, EC (Electrical conductivity), temperature, TDS (total dissolved solids), cations (Ca2+, Mg2+, Na+, K+), anions (HCO3-, SO4 2-, PO4 3- and Cl-). Several computed variables such as SAR (sodium adsorption ratio), SSP (soluble sodium percentage), hardness (HT), permeability index (PI), Kelly‟s ratio, potential salinity, Gibbs ratio and water quality index to evaluate the quality of water for specific uses. Almost all the water samples were acidic in nature (pH value varied from 5.70 to 7.25 for groundwater and 5.84 to 6.82 for surface water). All the samples were fresh on the basis of TDS (average 120 for groundwater and 80.63 for surface water). For hardness all the samples were moderately hard (average 213.05 for groundwater and 87.67 for surface water). Based on SAR and EC values, all samples were classed as „excellent‟ (average 1.44 for groundwater and 1.72 for surface water) and „excellent‟ (average 163.08 for groundwater and 118.82 for surface water) categories respectively for irrigation. On the basis of Ca, K, Na and Mg, content the entire water samples can safely be used for irrigation and would not affect the soils. Some correlations and compositional relations were also evaluated. The Water Quality Index indicate the quality of collected samples were good. In comparison with the national and international standards, the water sources of the study area were within the safe limit and recommended for irrigation, drinking and industrial purposes.