Summary:
With population growth, urbanization, and industrialization, both the volume of wastewater generated and its composition are undergoing significant changes. This situation leads to increased energy consumption and operating requirements in wastewater treatment plants. While wastewater treatment plants ensure wastewater is treated to a level that does not harm the environment, they are a significant source of carbon emissions from energy use, chemical consumption, and greenhouse gas emissions generated during treatment processes. Therefore, evaluating the carbon footprint of these facilities has become an important environmental sustainability issue. In this study, the potential carbon footprint of wastewater treatment plants and the main sources of emissions in these facilities are evaluated. In addition, studies conducted at wastewater treatment plants in Türkiye are examined, and the calculated carbon footprint values are compiled and summarized. The findings show that carbon footprint values vary depending on facility type, operating conditions, and wastewater characteristics. Differences also arise from calculation methods, data sources, and the definition of system boundaries. Overall, the results show that implementing energy-efficiency improvements, process optimization, and emission-control strategies to reduce the carbon footprint of wastewater treatment plants is of great importance for both environmental sustainability and climate change mitigation.