Chula Vista, California – Yesterday, U.S. Senator Laphonza Butler (D-Calif.) along with U.S. Senator Alex Padilla (D-Calif.) and U.S. Representatives Juan Vargas (D-Calif.-52), Sara Jacobs (D-Calif.-51), Scott Peters (D-Calif.-50), and Mike Levin (D-Calif.-49) called on the U.S. Department of State to press Mexican officials for answers on the unprecedented dry weather sewage and sediment flows from Mexico amid intense sewage odors.
The International Boundary and Water Commission has reported an increase in sewage flows in the Tijuana River originating from Mexico. To date, Mexico has not identified the origin of these flows.
“We write to you to express our deep concerns regarding the significant dry weather transboundary flows in the Tijuana River Valley, reports of increased sediment coming from Mexico, and the recent increase in odors coming from the Tijuana River Valley, and to urge you to press Mexican officials to address these issues as soon as possible,” wrote the lawmakers.
“Community members have reported that they cannot escape the persistent smell emanating from the Tijuana River. Residents of Imperial Beach and South San Diego County have shared that the sewage odors linger all day and night, frequently causing them to wake throughout the night from the smell. These increased flows affect the lives and livelihoods of the residents living near the Tijuana River and endanger the health and safety of our communities,” the lawmakers continued. “These conditions may be contributing to the oppressive odors that residents of San Diego have been living with, so it’s important that we understand what steps Mexico is taking to address the sediment and identify the source of the dry weather flows.”
The full text of the letter is available HERE and below:
We write to you to express our deep concerns regarding the significant dry weather transboundary flows in the Tijuana River Valley, reports of increased sediment coming from Mexico, and the recent increase in odors coming from the Tijuana River Valley, and to urge you to press Mexican officials to address these issues as soon as possible.
The U.S. International Boundary and Water Commission (IBWC) has informed us that sediment is building up near the Tijuana River, and they believe the build-up is due to an ongoing highway construction project in Tijuana, Mexico. As of June more than 3,815 tons of sediment and trash have been removed from the plant, which represents a nearly five-fold increase over last year. In addition to the high levels of sediment build-up near the Tijuana River, unidentified excess transboundary pollution originating from Mexico is causing unprecedented dry weather flows into the Tijuana River. The IBWC has told us they have brought this issue to the attention of the Government of Mexico, but to date, Mexico has not identified the origin of these flows.
As you may know, the IBWC’s Hollister pump station plays an important role in the IBWC’s ability to transfer and treat wastewater that flows from Mexico into South San Diego. On June 17, 2024, the IBWC reported that sediment build-up caused a surge tank pressure relief valve at the Hollister pump station to fail. This, in turn, caused a facility spill at the South Bay International Wastewater Treatment Plant (SBIWTP) that released 302,000 gallons of untreated wastewater onto the public right of way. Though the facility spill was cleared, the Hollister pump station remains offline, and, according to the USIBWC, nearly one million gallons of transboundary wastewater continue to flow through nearby canyon collectors each day.
The Hollister pump station failure has come at the same time as increased dry weather flows from Mexico. In addition, an intense odor that began around July 21, 2024, and continues to date, has resulted in the San Diego Air Pollution Control District issuing a notice of violation to the IBWC for the foul odor. While growing pollution in the Tijuana River has made sewage smells a fact of life for too many San Diego residents–especially during the winter rainy season – it is now present during the dry summer months.
Community members have reported that they cannot escape the persistent smell emanating from the Tijuana River. Residents of Imperial Beach and South San Diego County have shared that the sewage odors linger all day and night, frequently causing them to wake throughout the night from the smell. These increased flows affect the lives and livelihoods of the residents living near the Tijuana River and endanger the health and safety of our communities.
These conditions may be contributing to the oppressive odors that residents of San Diego have been living with, so it’s important that we understand what steps Mexico is taking to address the sediment and identify the source of the dry weather flows. Therefore, we write today on behalf of the constituents affected by the sediment flows, asking for answers to the following questions by September 6:
- Is the State Department currently taking or planning to take any other steps to convey to the Mexican government the harm that the sediment and the ongoing smells are having on residents of San Diego?
- Has the State Department considered issuing a démarche to the Government of Mexico regarding the excess sediment and dry-season flows? If not, what factors have led the agency to conclude that such a notice would not be appropriate in this instance?
- What communications has the State Department had with SEDENA, the Mexican defense ministry in charge of the highway construction project regarding this issue? What steps is the Department taking to ensure that SEDENA has a sediment mitigation plan in place for this construction?
- Does the Department require any additional support or authorities from Congress in order to address this ongoing issue? For instance, would it be helpful to the Department for members of Congress to share documented complaints that we have received from constituents regarding the odors from the transboundary pollution?
Thank you for your consideration. Because this is a dire situation, we look forward to receiving a timely response to the questions listed above.
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