The SBIWTP is a 25 million gallon per day advanced primary treatment plant South Bay International Wastewater Treatment Plant located in San Diego County, California, about 2 miles west of the San Ysidro Port of Entry. The physical - chemical plant treats sewage originating in Tijuana, Mexico and discharges it to the Pacific Ocean through the South Bay Ocean Outfall, a four and one-half mile long 11foot diameter pipe completed in January 1999. From here you can link to various informative pages about the SBIWTP located in San Ysidro, CA.

Nogales International Wastewater Treatment Plant, Nogales, Arizona

The Nogales International Wastewater Treatment Plant, (NIWTP) is adjacent and westerly of the Santa Cruz River/Nogales Wash confluence, about ten miles north of Ambos, Nogales. It treats a daily average dry weather flow of approximately fourteen million gallons, of which seventy per cent is from Mexico. For thirteen years, it has employed oxygenated pond technology and industry – standard chlorination/dechlorination for effluent disinfection. It is expected that a $60 million upgrade, to be online by 2009, will use best available technology, in response to continuing stricter discharge permit requirements.

Nuevo Laredo Wastewater Treatment Plant, Nuevo Laredo, Tamaulipas

The purpose of the Nuevo Laredo Wastewater Treatement Plant is to collect and treat sewage from Nuevo Laredo to standards applicable in the United States as agreed to by the International Boundary and Water Commission. The project is located in Nuevo Laredo, Tamaulipas, Mexico at the confluence of the Rio Grande and the Coyotes Arroyo. The project was authorized by International Boundary and Water Commission Minute No. 279, Joint Measures to Improve the Quality of the Waters of the Rio Grande at Laredo, Texas-Nuevo Laredo, Tamaulipas, signed August 28, 1989. Construction began March 17, 1992. The plant was substantially completed and became operational in 1996 with a dedication ceremony on April 17th of that year. Work continued for the next few years on the plant’s remaining items, including completion of an additional 56 sludge drying beds. A 1997 agreement of the International Boundary and Water Commission provides for U.S. participation for 33% of the total cost of operating and maintaining the plant through 2005.