Deterioration of wastewater treatment processes in Iraq: A case study from Al-Samawah

Wastewater treatment is one of the main elements in reducing water pollution in any country. Wastewater treatment plants (WWTPs) in Iraq are facing high challenges due to improper management. Till now, these WWTPs may be considered the major polluter of the country's water bodies. Al-Samawah WWTP, located in Al-Muthanna Governorate, was taken as a case study to analyze the processes in these plants. The plant was visited, available data was collected, and the staff responsible for operations was interviewed. Data analysis showed a deficiency in treatment since the beginning of the plant's operations mainly due to improperness in the design, construction, and management of the treatment train. As of now, there are approximately 76.9E+05 kg of BOD5, 3.24E+06 kg of TSS, 4.01E+07 kg of TDS, 1.55E+06 kg of COD, 9.35E+04 kg of nitrates, 1.097E+0 kg of ammonia, 8.90E+06 kg of sulfates, 2.08E+03 kg of phosphates, 1.57E+06 kg of oils and greases, and 1.74E+05 kg of hydrogen sulfides are loaded annually to Al-Samawah River from the plant making it as the major polluter in the Governorate. There is no measurement for the level of contamination with heavy metals, hydrocarbons, and other toxic materials, but they are expected to be high as well. The highest average change from one period to the next in a model of linear trend analysis was noticed in contamination with oil and grease (ß1=2.311) indicating a high level of deterioration in the process. Discharged wastewater may exceed the standards for BOD5, COD, TSS, NH3, O&G, and H2S concentrations for 1.6, 0.88, 8, 3.36, 119, and 20.2, times respectively. A long list of correction measures is recommended to be implemented in order to comply with the minimum water pollution prevention standards in the country.