Evaluation of effect of wastewater application on saturated hydraulic conductivity of soil

The increasing population in India and many other countries has not only increased the freshwater demand but also increased the volume of wastewater generated. Wastewater reclamation and reuse has now become an important element in water resources planning and management. Wastewater is potentially an important water source for irrigation to some crops. However, degradation of soil hydraulic properties is one of the expected risk of wastewater reuse. The present paper evaluates the effect of wastewater application on saturated hydraulic conductivity (K_s) of soils of the selected two fields (Field-I and Field-II) located in RAU, Pusa campus in Bihar (India). The study indicated that K_s decreases with increase in amount of infiltrated natural wastewater (NWW) or artificial wastewater (AWW). The decrease in K_s with respect to that for freshwater (FW) application varied from about 10 to 20% depending upon the clay content of the soil. Further, the percentage (%) decrease in average value of K_s was found to be greater (14.33%) in the Field-II than Field-I (9.40%) in case of NWW application. Similarly, the percentage (%) decrease in case of AWW application was found to be 18.61% in the Field-II compared to 12.41% in the Field-I. Sealing effect of wastewater application to soil of Field-II was found more than that of Field-I due to higher clay percentage in the former field.