Comparative physico-chemical characterization and spatial distribution of pollutants in rural and urban drains water

The present study was conducted to compare the pollution level of rural and urban drains water in Dinga, Gujrat, Pakistan. The water samples were collected randomly from five sampling points of rural and urban drains each, and total of 29 physico-chemical parameters were analyzed. The comparison of mean values indicated that urban drain was relatively more polluted compared to rural drain. The highly significant difference (p< 0.01) was recorded for the levels of pH, biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total dissolved solids (TDS), an-ionic detergents, sulphates, sulphide, ammonia, chromium, copper, nickel, total toxic metals, zinc, iron and chlorine; while the significant difference (p< 0.05) was found for grease & oil, fluoride and nickel between rural and urban drain. Furthermore, the physico-chemical parameters varied significantly (p< 0.01 or p< 0.05) within different sampling points of each drain. The experimental results of different quality parameters studied in both the drains were interpolated in GIS environment using kriging techniques to obtain calculated values for the remaining locations of the drains. In conclusion, most of the pollutants were in range of NEQS guideline values, but still the risks of increased contamination of water resources cannot be excluded, which may be hazardous for local population. Therefore, there is an urgent need to protect the natural streams from further degradation. These results can be helpful for future management of other polluted drains and small streams in the same eco-region.