Ambos Nogales Effluent
Perennial flows in the United States of America (US) portion of the Santa Cruz River downstream from the Nogales International Wastewater Treatment Plant (NIWTP) depend on its effluent discharges. The US portion is subject to high variability in flows, due to both wastewater overflow events resulting from heavy rainfall, and decreases in flow resulting from treatment and discharge of Mexican wastewater by Mexico.
The diversion of wastewater generated from NIWTP has the potential to have social, institutional, hydrological, and ecological effects to the Ambos Nogales region (Nogales, Arizona and Nogales, Sonora). Coupled with this change in discharge are potential stressors due to climate variability. The difference in institutions and legal frameworks north and south of the US/Mexico border further complicates water management efforts.
The following analysis focuses on the institutional setting for wastewater treatment and effluent in the Santa Cruz Aquifer Basin. The article describes the physical and legal background of the region and how those factors will impact future management decisions. The article closes by discussing future plans regarding effluent water on both sides of the border.
Information for this article was gathered from a literature review on NIWTP, the Santa Cruz River Aquifer, and policies in the US and Mexico. Five interviews were conducted with representatives from Mexican and American government agencies operating in the Ambos Nogales region.