Waste not, want not? Evaluating the urban sustainability implications of centralized versus decentralized wastewater treatment in Tijuana, Mexico

Abstract

Rapid, unregulated urbanization in Tijuana, Mexico outpaces the city’s wastewater treatment capacity. Efforts to incorporate water reclamation and resource recovery technologies into the city’s treatment network present an opportunity to improve regional public and environmental health without relying solely on the region’s limited water resources. I compare two sustainable wastewater treatment technologies used in Tijuana to better understand their contributions to the city’s attempts to increase economic, social, and environmental sustainability. A sustainable indicator analysis reveals that both facilities utilize water reuse technologies and support reforestation programs. While the smaller-scale, alternative plant makes important contributions to reforestation, slope stabilization, and community education programs, it lacks the capacity and treatment standards of the large-scale, centralized plant to meet the current and future needs of Tijuana. However, I argue that if the final water quality produced by smaller-scale, alternative technologies can be improved, these types of facilities have the potential to augment larger-scale treatment plants and provide important, localized sustainability benefits in a transborder context.