Authors: Jacob Petersen-Perlman*, University of Arizona
Topics: Water Resources and Hydrology, Political Geography, Human-Environment Geography
Keywords: groundwater, transboundary water, water quality, water cooperation
Session Type: Paper
Perennial flows in the U.S. portion of the Santa Cruz River downstream from the Nogales international Wastewater Treatment Plant (NIWTP), as well as groundwater recharge for the Santa Cruz River Aquifer, are dependent upon effluent discharges from the plant. Past excesses produced from the plant, combined with heavy rainfall, represented environmental and economic impacts to both nations, as overload from the NITWP has led to discharges of wastewater flowing directly into the Santa Cruz River, discharging raw sewage, trash, and industrial wastewater laden with heavy metals. In partial response to this, Mexico built the Los Alisos Wastewater Treatment Plant in 2012, which would divert wastewater from Nogales, Sonora, Mexico to the plant, instead of it being treated at the NIWTP. The diversion of wastewater, and future heavy rainfall events, have the potential to have social, institutional, hydrological, and ecological effects to the Ambos Nogales region (Nogales, Arizona and Nogales, Sonora). The differences in institutions and legal frameworks north and south of the border further complicate water management efforts. This presentation will analyze the institutional setting for wastewater treatment and effluent in the binational Santa Cruz Aquifer Basin. We investigate how existing institutional frameworks on both sides of the border influence the distribution of effluent, and how options for discharging effluent will change conditions for groundwater recharge.