ASSESSMENT OF PHYSIO-CHEMICAL PROPERTIES OF GROUND WATER IN THE SOUTH WESTERN COASTAL ZONE OF BANGLADESH

Abstract

Groundwater quality is deteriorating due to contamination of various pollutants from different anthropogenic functions and salt water intrusion in the coastal regions of Bangladesh. Three coastal villages denoted as shoreline (Rajoir), interim (Gangarampur) and inland (Ganopatipur) areas of south western coastal zone of Bangladesh were purposively selected to determine the temperature, pH, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), dissolve oxygen (DO), total hardness (TH), chloride (Cl-), potassium (K+) and calcium (Ca++) ions. A total of 40 water samples were collected from 20 sampling sites based on the maximum water use declared by local communities. Temperature, pH, EC, TDS and DO were measured onsite and TSS, TH, Cl-, K+ and Ca++ were measured in the laboratory. Based on the EC values 100% water samples were within the desirable limit (1500 μS/cm). TDS classification showed that 100% sampling station’s water were fulfilled the criteria for irrigation purpose in shoreline area and 100% sampling station’s water were within desirable category in inland area. The study revealed that the trend of EC, TDS and Cl- concentrations were decreased from shoreline to inland villages, respectively. The study resulted the positive correlation between EC: TDS (r=0.712), TDS: Ca (r=0.585), DO: K (r=0.5041), Cl- : K (r=0.581), K: Ca (r=0.635) showed homogeneous sources of variables and same anthropogenic activities might be responsible for the excess concentrations in the study area. So, the water should not be used for drinking purpose without any proper treatment.