Reading the investigative Coronado News articles about ocean pollution, I began to understand most citizens and government leadership are not aware of the actual sources that cause most of the chronic cross-border pollution from Mexico.
Here is a summary of these pollution sources and the technology to largely solve and
restore our ocean environment.
U.S.-owned plant dumps sewage in Pacific
Current IBWC Plant and SBOO Discharge: The US owned sewage treatment plant has been dumping an average of 27 million gallons per day (mgd) of untreated Mexican sewage into our ocean for seven months through the City of San Diego Ocean Outfall (SBOO) pipe.
The IBWC sewage plant can only work efficiently at a constant volume of about 25mgd. It cannot vary its volume because the chemistry of sewage treatment process requires a constant volume.
So, if the volume of wastewater changes, it must dump the sewage water directly into the ocean untreated.
While US sewage plants have predictable flow rates, Mexico’s sewage system varies wildly by rainfall and chemicals from maquiladora factories.
Mexican sewage plant shut down
San Antonio de los Buenos Plant (SAB) – For the last seven months, the SAB plant has been shut down and has not been a source continuous pollution.
By simple process of elimination if the SAB plant has been shut down and the IBWC plant pumps continuously, then the IBWC plant must be considered as the major source of
The past assumption of the EPA Scripps Modeling study claiming that the SBOO is not a major source of sewage to our coastal shoreline is false and must be corrected.
These coastal water modeling studies, when first hypothesized, did not include the data of eastern onshore flow from the well documented Coronado Littoral Cell. (Inman, Scripps 1976).
Also the continuous water testing data at the Bullring surf zone over the last 20 years has had few positive tests for pollution when compared to Imperial Beach.
Imperial Beach citizens have a plan
Citizens offer an Alternative Plan – Imperial Beach citizens provided a plan to solve the constant volume problem three years ago.
These citizens recommended installing a canyon collectors with Flow Equalization
Basins (FEBs) in the Tijuana River.
The past 20 years of history shows the other canyon collectors operated by the IBWC are very efficient at collecting sewage.
No other system even comes close to this system of wastewater collection and remediation. The new FEBs use no energy and store 300mg of sewage, which allows the plant to operate at a constant volume.
A continuously operated plant would reduce beach closure days to less than 70 days per year which is the same as closures for rain.
EPA plan will boost wastewater dumping
EPA USMCA plan versus Flow Equalization Basins – If the EPA USMCA plan is completed it will increase sewage wastewater dumping by 300%.
The same problem of uneven flow will cause shutdown of the plant and we will again have raw sewage from Mexico directly dumped into the ocean.
In addition, we will have the sustaining pollution source of the plant’s operation.
The EPA plans on cleaning 40 million gallons a day of water and sending the clean water back to Mexico while our coastal ocean receives the wastewater and sludge from this plant’s new operations.
The USMCA plan contradicts the 2019 EPA plan of four years ago which was simple to implement and required Mexico to maintain the pump equipment.
Through the inspection of Mexico operations and equipment the 2019 Arcadis Report showed that by operating the equipment in Mexico correctly and with simple maintenance, BMPS would keep beach closures to less than 70 days a year.
Plan is clear
The FEBs advantage over USMCA plan is clear.
We would eliminate sewage off the coast, provide a ROI of 37%, recharge our ground water table, provide a safety net of water, restore the Tijuana River aquifer, and restore the 12,000-acre feet of water right which belongs to the ranchers and people in the County of San Diego.
A project recently completed in Orange County shows that a $491 million investment returns 37% on investment each year and produces 130mgd of drinking water.
Think about the comparison of these two plans for a moment. Our government officials are asking for emergency action and more funds above the $300 million the EPA just asked for in 2019.
The USMCA plan is the same Al Gore/Bob Filner project has which failed to solve the sewage problem for the last 30 years.
Leon Benham is an organic farmer/environmentalist who has lived in Imperial Beach for 60 years. His small-scale farm is located next to the Oneonta Slough, where he teaches children how to garden food for the last 20 years. Professionally he has acted as a Chief Estimator/Project manager on numerous environmental projects including the Bayshore Bikeway, Tijuana Trails, Spooners Mesa Trail , habitat restoration and river restoration projects including cleaning up below grade aquifers for the last 24 years.
Correction: A previous version incorrectly stated the number of gallons put through the international wastewater treatment plant. The correct figure is an average of 27 million gallons a day.