Raw sewage is flowing into the Tijuana River Valley.
A private developer inadvertently damaged a 60-inch pipe on Feb. 10 which led to the spillage, according to the International Boundary and Water Commission.
Most of the sewage is spilling into Smuggler's Gulch and Goat Canyon.
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βIn the wastewater sewage you have bacteria, itβs basically waste from residential units and industrial units. So, it could be heavy metals, it could be pollutants, bacteria and everything that is most impactful to our environment,β said San Diego State University Professor Hassan Davani, Ph.D.
According to the IBWC, field crews are working 18-hour days to stop the flow of sewage.
The most recent incident isnβt the first-time sewage has spilled across the border.
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βThis is a very historic issue going back mid-century in the previous century. There are records that this happened and show a lack of infrastructure to treat these volumes of wastewater,β Davani said.
Experts urge a long-term solution that prevents sewage from spilling because of the lasting impact.
βIf this problem persists five, 10 or 20 years from now, we are basically talking about part of our community impacted harshly because of all of the pollution, all of the bacteria and all those issues with the raw sewage,β Davani Ph.D. said.
The IBWC expects to stop the transboundary flow of sewage due to the damaged pipeline by Feb. 22.