Wastewater Treatment: A Solution for Climate Mitigation and Methane Reduction

The event began with an introduction to the topic and highlighted the transformative role of wastewater treatment in the context of climate change. Global efforts led by UNEP and other international entities to highlight climate change mitigation opportunities that can arise from proper wastewater management were addressed.

The participation of Dr. Silvia Saravia Matus from ECLAC focused on sharing the results of an exhaustive analysis on the implementation of circular economy practices in wastewater treatment plants in Latin America and the Caribbean. In her presentation, the official explained how less than 50% of the region’s wastewater receives adequate treatment, which contributes to high levels of pollution, with 25% of rivers experiencing severe impacts. This panorama, aggravated by increasing water stress in urban areas and infrastructure inefficiencies, underlines the need for a structural transformation in water resources management.

Dr. Silvia Saravia Matus highlighted a study carried out in 75 treatment plants in intermediate cities in countries such as Mexico, Costa Rica, Colombia, Peru and Bolivia. According to the analysis, investments of approximately $250 million would be required to recover methane in these facilities, which would allow annual energy savings estimated at $46 million. Calculations suggested payback periods of six years and a positive benefit-cost ratio. Additionally, the results of a similar project in smaller municipalities in Mexico and El Salvador were presented, where more modest investments of $5 million proved to be highly profitable with significant annual savings and payback periods of less than six years.

The presentation also highlighted concrete examples of implementation. El Salvador has decided to advance investments in specific plants evaluated by ECLAC, while Colombia has requested to expand the study to 100 additional plants in intermediate cities, in collaboration with UNEP. These initiatives not only aim to generate economic benefits, but also to reduce air and water pollution, and mitigate biodiversity loss in the region.

The event concluded with a lively Q&A, where participants discussed the feasibility of scaling these solutions and the challenges in closing the technical and financial capabilities gap in the sector. Dr. Saravia underlined the importance of providing solid evidence to policymakers to accelerate the incorporation of circular economy principles in wastewater treatment at different scales. The event served as a call to action to prioritize sustainable wastewater management as a strategic pillar in the global climate agenda.