As a result of efforts by the Mexican government’s interagency work group, the Mexican Section of the International Boundary and Water Commission, United States and Mexico (IBWC) has received 83.982 million pesos (about 3.6 million U.S. dollars) from Mexico’s National Water Commission (Conagua) to rehabilitate Pump Station CILA in Tijuana, Baja California. These resources represent the first payments from the plan announced by the Mexican government last October to address the problem of transboundary wastewater spills in the Tijuana River.
These actions are expected to bring about substantive improvements in the quality of life of residents of the border communities of Imperial Beach, California and Tijuana, Baja California. Once this work is completed later this year, it is expected to reduce the volume of transboundary river flow to San Diego County, California during the dry season by 70 percent. Tijuana River flow during the dry season consists primarily of treated and untreated wastewater so this reduction will benefit public health on both sides of the border.
The money received by the Mexican Section of the IBWC will be used to improve the operation and efficiency of Pump Station CILA by constructing a new pump intake and a sedimentation tank to remove silt, among other improvements. These changes will reduce the trash that clogs the pumps, reducing the time the pump station is out of operation for cleaning. As a result, the number of spills and transboundary flows will decrease.
The work is made possible by an agreement signed in September 2019 between the Mexican Section of the IBWC and the Government of the State of Baja California, which transferred operation and maintenance of the Tijuana pumping plants to the Mexican Section of the IBWC to improve the system’s reliability. In addition to the Mexican Section’s project, the Tijuana utility (CESPT) is planning to install three new pumps that are expected to be put into service in July.
“With these upgrades, we expect to see significant improvement in the Tijuana River Valley during the dry season,” said Jayne Harkins, Commissioner, U.S. Section of the IBWC.
Jesus Luevano, Mexican Secretary of the IBWC, said, “These improvements will help to reduce transboundary spills to the United States, benefitting the health of residents on both sides of the border.”
Pump Station CILA, completed by Mexico in October 1991, is located approximately 1,200 feet (400 m) upstream from the international boundary between the United States and Mexico. This pump station diverts water from the Tijuana River channel into the City of Tijuana’s sewer system, preventing the runoff from entering the United States.
The International Boundary and Water Commission, United States and Mexico, is responsible for applying the boundary and water treaties between the two countries. The U.S. Section of the Commission operates and maintains the South Bay International Wastewater Treatment Plant in San Diego, which treats 25 million gallons per day (1,100 liters per second) of sewage from Tijuana that would otherwise flow through the Tijuana River into the United States.