SAN DIEGO (CNS) — Sewage flow across the U.S.-Mexico border may temporarily increase in the Tijuana River Valley as part of a sewer line-repair project in Mexico starting this week.
In a news release issued Friday, the county Air Pollution Control District announced the project could also increase pollution at South County beaches, as untreated wastewater is diverted south of the border.
Now in its second and final phase, the project is expected to start Tuesday and take roughly one week to complete, APCD officials said.
The existing line moves untreated wastewater to the South Bay International Wastewater Treatment Plant in the U.S., and the San Antonio de los Buenos Plant in Mexico, according to the APCD.
"The completion of this line is critical for preventing potential catastrophic failures and increasing reliability of Tijuana's wastewater infrastructure," the APCD stated.
The International Boundary and Water Commission will stay in touch with construction and project managers in Mexico, monitor progress and share updates, according to the ACPD.
The IBWC "has been working extensively with Mexico to mitigate wastewater spills as much as possible and have coordinated bypass lines to pump as much wastewater as possible" to the South Bay plant, according to the county.
The IBWC, U.S. Environmental Protection Agency, state Department of Public Health, San Diego Regional Water Quality Control Board, the APCD and county government have collaborated since last year on sewage treatment issues.
The APCD monitors odor complaints and hydrogen sulfide levels for communities located near the Tijuana River Valley.
According to the county, residents in affected communities can reduce the impact of the hydrogen sulfide odors by limiting outdoor activities if the smell bothers them.
The county also advises keeping doors and windows closed, using fans or portable air condition to increase circulation indoors and using an air purifier with a high-efficiency particulate air filter, activated charcoal and potassium permanganate.
According to the APCD, people with chronic conditions such as asthma or chronic obstructive pulmonary disease should have their rescue medications readily available.
Residents should seek medical care if they experience persistent or worsening symptoms caused by strong odors, officials added.
The APCD offers free purifiers for residents who qualify.
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