Nogales Wastewater

1. Purpose and Objectives: The purpose is to provide adequate treatment for the Ambos Nogales area to protect public health and the environment. Objectives include providing more treatment capacity for Nogales, Sonora, and implementing an effective pretreatment program.

2. Funding: EPA has given $47,500,000 to USIBWC for this and other border wastewater projects. EPA has given the Arizona Department of Environmental Quality (ADEQ) a grant to provide technical assistance on the project. Additional U.S. funding for this project could come from EPA in future years, based on consultations with BECC and NADBank. In addition, EPA has provided USIBWC $200,000 for development of a pretreatment program.

3. Partners: Primary U.S. partners USIBWC, ADEQ, Arizona Department of Water Resources, Santa Cruz County (Public Works) and Nogales, Arizona. Primary Mexican partners are MxIBWC, CNA, State of Sonora, and the city of Nogales, Sonora.

4. Description: The Ambos Nogales area is currently served by the Nogales International Wastewater Treatment Plant (ITP). However, deficiencies in the system result in raw sewage flowing across the border into the Nogales Wash and adjacent washes. Also, Nogales, Sorona, is utilizing its full capacity at the ITP and additional capacity is needed. The project involves planning, design, and construction of wastewater collection, conveyance, and treatment facilities, and will be done in coordination with planning for the potable water supply project certified by BECC for Nogales, Sonora. The project also involves the development and implementation of an effective pretreatment program.

5. Status: Preparation of a binational facility plan in accordance with IBWC Minute 294 has yet to be initiated. In the meantime, the Nogales, AZ, with grant funding from the EPA, has made some immediate improvements (quick fixes) to its collection system and is identifying further improvements to minimize infiltration and inflow (I/I) into the system. A binational I/I study of the Nogales, Sonora, collection system may also be initiated. An IBWC consultant is calculating the maximum levels of toxic pollutants that can safely be treated at the ITP (headworks analysis). IBWC will then allocate the allowable amounts to the two countries, which will regulate users of the system to ensure compliance.

6. U.S. Contacts: Evelyn Wachtel, EPA Region 9, (415) 744-1167 Armando Roam, USIBWC, (915) 534-6605 Mario Castaneda, ADEQ, (602) 207-4409 Hugh Holub, City of Nogales, AZ, (602) 287-6571