Effect of Climatic Conditions on Treatment Efficiency of Wastewater Stabilization Ponds at Chokera, Faisalabad

Wastewater management is one of the biggest challenges in the world due to increase in population and industrialization. In Faisalabad (FSD), wastewater treatment is being done through Wastewater Stabilization Ponds (WSPs) at Chokera, which is one of the most economical methods of Wastewater Treatment (WWT). Various parameters were examined to check wastewater treatment efficiency of the ponds under diverse climatic conditions. These included Biochemical Oxygen Demand (BOD), pH, Chemical Oxygen Demand (COD), Turbidity, Copper, Total Solids (TS), Total Dissolved Solids (TDS) and Lead. Six locations which were selected for monitoring treatment efficiency, included inlet and outlet of treatment plant, influent of anaerobic ponds, effluent of anaerobic ponds, effluent of facultative ponds, and Pharang drain before and after blending with treated sewage. The testing was performed in two seasons (i.e. Winter 2015 and Summer 2016) in Environmental Engineering Laboratory, Department of Civil Engineering, The University of Lahore, Pakistan. BOD5 removal efficiency of the treatment plant was found 30.08% in winter and 51.74% in summer against designed value of 90% removal. Most of the parameters of the effluent were not meeting the Punjab Environmental Quality Standards (PEQS). The reasons of low efficiency are; variation in climatic conditions (i.e. less solar heat intensity, wind speed and ceased microbial activity in winter), lack of funds by government, increased population, mixing of industrial sewage with domestic sewage and less attention being paid to maintain the performance of Ponds. The study was carried out to assess and compare the efficiency of treatment plant with PEQS in two climatic conditions.