The mutual impacts of climate change and wastewater treatment: Critical review of challenges and solutions

Climate change has caused significant challenges to sustainable development in agriculture, industry, and infrastructure. Wastewater treatment, as a fundamental urban infrastructure in promoting sustainable city living, has also faced drastic problems due to climate change. These problems include changes in the volume and quality of influent wastewater, sewer overflows, damage to treatment plant infrastructures, and a reduction in overall treatment efficiency. Wastewater treatment also intensifies climate change effects through fossil fuel burning, greenhouse gas emissions, and marine eutrophication. Life cycle assessment as an effective tool for analyzing the mutual impacts of climate change on wastewater treatment processes indicates that the adoption of novel technologies transforms treatment plants from energy consumers into energy producers. Furthermore, the co-treatment of food and organic waste with conventional wastewater has led to a reduction in greenhouse gas emissions and an increase in biogas production. Additionally, optimizing stormwater treatment unit design and sludge management can reduce fossil fuel-related emissions by up to 84 % and non-carcinogenic human toxicity by up to 56 %. Given the reciprocal negative effects of climate change and wastewater treatment, it is necessary to seek practical approaches (such as reusing treated wastewater, bio-electrochemical processes and membrane bioreactors, constructed wetland, and biochar) to address these negative impacts. Utilizing new methods of wastewater treatment decreases energy consumption, increases plant efficiency, and provides economic benefits. This review provides a comprehensive insight into rectifying the wastewater treatment process for reducing the adverse effects of climate change and supports selecting cost-effective management strategies for decision-makers and plant managers.