A Border Tragedy
Guest contributor: Rita Schmidt Sudman, San Diego, California
There was no smell that day and the ocean looked normal.
As I walked along the ocean at Imperial Beach enjoying the sun casting shadows on the waves, several families were wading into the water, not noticing the patrolling lifeguard warning that the water was too polluted for swimming. I wondered if some swimmers heard the warning so many times – often over 200 days a year - that they became immune to the notice. After all, there was no smell that day and the ocean looked normal.
What had gone so wrong that we could not swim in the ocean in an American city?The problem of Mexican sewage water polluting southern San Diego beaches has been going on for decades. Additionally, thousands of noxious odor complaints by residents of the south county are filed annually with the local air district. Residents complain of nausea, headaches, vomiting, dizziness and respiratory complications. What was once viewed as an environmental problem has become a major public health issue.
Rita Schmidt Sudman, a resident of San Diego, is co-author of a book on California water issues, Water: More or Less. Former executive director of the Water Education Foundation, she is currently involved with Tijuana River sewage issues.
Controversy has raged for decades on the cross-border sewage issue.
A country with plenty of financial resources borders a country with many less resources. The fast-growing city of Tijuana cannot keep pace with the sewage from the city’s population explosion. Previous fixes on both sides of the. Border became overwhelmed with the increasing amounts of sewage from the Tijuana River and broken Mexican and American treatment plants. To the people swimming at border beaches and breathing the air, there is no distinction as to where the pollution comes from–the River or the broken treatment plants.
By 2024, under increasing public pressure Congress. added $250 million to the earlier pledged $300 million to fix the sewage overwhelmed U.S. South Bay International Wastewater Treatment Plant. Still longtime observers note that we’ve been down this road before with promised fixes that get overwhelmed by the growing problem. Residents in low-income communities near the border bear the brunt of these effects, and polls show 71% of the local border residents now distrust the safety of their tap water, although that water is from an entirely different and safe system. Also the economic toll on tourism in the San Diego area has been significantly affected annually due to beach closures. Whether democrats or republicans are in power, hopefully any fix will keep federal funding flowing to solve the problems of border water and air pollution.
Geography: “a toilet flushing into the U.S.”
The Tijuana River is one part of the problem. The River has been functioning as a wastewater channel for more than 100 years and is sometimes called “a toilet flushing into the U.S.” Millions of gallons of sewage water enter the U.S. and flows through the Tijuana River Valley and estuary before entering the ocean north of the border. The River actually flows on both sides of the Border. A tributary of the river starts in the arid mountains of San Diego County where it is dammed a couple of times for local water supply. The river then crosses the border into Mexico where it picks up trash including old tires, a tremendous number of plastics and raw sewage that empties into the Tijuana estuary on the U.S. side. When it rains, the problem of sewage and trash going into the estuary is worse, affecting the largest remaining salt marsh and bird refuge in Southern California. It’s been the Mexican government’s official position that once the sewage spills over to the U.S. side, it’s out of their jurisdiction.
Mexican treatment plants have been broken for decades
The other part of the sewage problem, unrelated to the Tijuana River, is that Mexican treatment plants have been broken for decades. The Punta Banderas plant, six miles below the U.S. border, creates a discharge that doesn’t meet Mexican water standards and certainly not U.S. standards. Eyewitnesses describe “pools of poop” escaping, flowing through a canyon and into the ocean, polluting beaches 20 miles north, all the way to the famed Hotel Del Coronado. To rebuild this plant, the Mexican government finally gave building authority to their military in 2025
A brief look at the history of the people on both sides of the border shows Americans and Mexicans are very connected. The arbitrary line creating this international border was drawn after the U.S. defeated Mexico in 1846 claiming America’s “Manifest Destiny” to control the continent from coast to coast. The Americans got San Diego Bay and a line was drawn several miles south of the Bay, intersecting the Tijuana River. For many decades, people and goods moved fairly freely across the border area. Just look at old movies showing the easy passage of people and talk to Mexican and American families, like my own, who went back and forth across the border for shopping and tourism.
Americans flocked to Tijuana with U.S. Prohibition laws
The problems with cross border sewage didn’t happen overnight and involves both Americans and Mexicans in the business and cultural life of the border. Americans flocked to Tijuana after the advent of the U.S. Prohibition law when the city was open to bars, gambling and other activities. Mexicans from the interior began crowding Tijuana for work opportunities, overwhelming the city’s sewage system. Explosive growth continued and the population of the city grew ten times between 1940 and 1960.
Part of that growth involved cross border employment. Early in WWII, the U.S. needed workers to harvest crops, so a “bracero” program was created allowing up to almost half a million Mexicans to work as contractors in the U.S. and cross the border back and forth before the program was discontinued in 1964. Still the border area kept growing. Since the 1970s, Mexican workers have been assembling American-made products in Mexico. With the creation of NAFTA in 1994, more American companies moved below the border. By 2000, Tijuana contained about 2 million people compared to San Diego’s 1.5 million. Tijuana is the fourth busiest land border crossing in the world.
History of Solutions
Beginning in the 1930s, efforts have been made to solve the Mexican sewage problem. First the Mexicans piped their sewage out to sea. This only worked until the early 1950s when U.S. health officers strongly objected to this method and the Mexicans began to treat their raw sewage with chlorine before putting it in the ocean. By the early 1960’s, an emergency link from Tijuana to a U.S. treatment plant was completed to treat millions of gallons a day. Through the years, the U.S. has treated Mexican sewage in varying amounts.
A cycle of building improved treatment plants on both sides of the border resulted in systems being overwhelmed. Two treatment plants now exist on the Border, one run by local U.S. authorities and one international plant built in 1998 on the U.S. side of the border to also handles some Mexican sewage. Both plants suffer periodic breakdowns and need increased maintenance.
“A tsunami of sewage”
Beach closures continued mainly due to that broken treatment plant at Punta Banderas. Disaster was compounded in 2017 when a Mexican sewage pipe broke and was not reported or quickly fixed. The mayor of Imperial Beach called the Mexican spill “a tsunami of sewage.” By this time, several dozen Customs and Border agents, surfers and untold numbers of migrants were affected by contact with sewage. Finally in 2019, a powerful group of city and county, regulatory and interest groups sued the International Boundary and Water Commission, a U.S. and Mexican governmental organization.
Another flood of attention came in 2020, after the television program “60 Minutes” examined the problem on both sides of the border. Five retired Navy Seals talked about being seriously affected by the polluted water at their training site just north of Imperial Beach. Still the Navy never acknowledged the seriousness of the problem. The training beach is prime real estate and that may be the reason the Navy Brass told Congress that the problem is “infrequent and short term.” Finally in February 2025 the Navy formally acknowledged the problem after the Department of Defense released a report by the inspector general confirming that SEAL candidates frequently train in sewage-tainted waters resulting in hundreds of cases of acute gastrointestinal illnesses. About 40% of the recent cases of illness were directly tied to contaminated waters. In tested samples, 75% exceeded state safety levels.
Recently, as the water and air pollution has gotten worse, there have been calls for emergency declarations from the state and federal government. A request to declare the Tijuana River Valley a Superfund site was rejected by the U.S EPA in 2024. Critics say the EPA based their decision on 6-year-old pollution data. It seems like no agency wants to take responsibility to find a comprehensive solution.
The Blame Game
While it’s common for Americans to blame Mexico for the border sewage problem, both sides have benefited from a strong transborder economy and will benefit from solutions. Already, critics say the current plans are millions short of what’s needed. In fact, one study estimated almost $700 million is needed for a comprehensive fix. Congress’ initial $300 million funding is part of the United States-Mexico-Canada Agreement - replacing the 1994 NAFTA agreement. EPA’s announced in 2024 a plan to double the current funding to $630 million. The money comes with a request for some of the funding to solve the problem at the source on the Mexican side – at Punta Bandera and other locations. While this makes some sense, U.S. authorities are concerned that, even with U.S. help, Mexico will not be able to maintain the improved systems, a past recurring problem. San Diego area Congressman Scott Peters says he is not averse to spending some money on the Mexican side of the Border but asks the Mexican officials, “What are their plans? What are their commitments? We want to know that they will be able to maintain it and money won’t disappear.” Currently maintenance problems continue.
Plans are to solve part of the problem by channeling that Mexican sewage to an expanded South Bay International Wastewater Treatment Plant which will handle double the amount now processed. Fixing that plant will take years and current problems continue due to broken Mexican pumping stations releasing millions of gallons of sewage. To put the numbers in perspective, scientists say that in the last two decades, the Mexican sewage flowing over the border is roughly equal to all the water in Lake Tahoe!
Money has always been a defining issue. Unpaid taxes in Mexico both by American, foreign, and Mexican companies also have hampered the Mexican government’s ability to build the necessary water infrastructure by collecting the revenue they need. Dr. Gabriela Munoz Melendez, professor and researcher for the Mexican think tank COLEF notes, “There are many American companies that were not paying a thing or very little for water.” Fay Crevoshay, policy director of WILDCOAST, a nonprofit border environmental group agrees, “Some people (in Tijuana) don’t pay taxes including 65,000 squatters living with no services.” Although Mexico has very many good environmental laws on the books, there is little enforcement and only a few companies comply with environmental regulations, according to Fay Crevoshay. “Mexico has laws up the Ying Yang but no application of laws – people making it a live document.” Unlike in the U.S. where citizens and third parties often successfully take polluters to court, these types of lawsuits are not allowed under Mexican law.
Another issue is that water also has been used for political and election issues according to Vincente Calderon, editor of Tijuanapress.com. “Public services have been used as petty cash for political campaigns.” The problem is complicated by the Maquiladoras, foreign companies operating in Mexico with duty and tariff free imports and exports. He said that of the approximately 1,000 Maquiladoras only a fraction of them are socially responsible and compliant with laws to treat water.
Long-time observers from U.S and Mexican interests, press and governmental groups all agree that open communication and transparency is necessary in deciding how to spend the U.S. and Mexican funds. The difference between the ways the Mexican government functions – top down- and the way the U.S. government works – more bottom up was noted as part of the challenge of working together. Even with all the obstacles to better water quality on both sides of the border, the experts agreed that progress would be made now that potential projects finally have been selected by the EPA. The EPA estimates that about $566 of the total $630 million would be paid by the U.S. and the remainder by Mexico.
Trump promises to provide speedy 100% solutions in 100 days
A new twist was a surprise announcement in May 2025 when the Trump administration pledged to accelerate the expansion of the deteriorated South Bay International Wastewater Treatment Plant from the planned update of 2 years to 100 days. The Trump administration says their “aggressive leadership:” will achieve a 100% solution to the Mexican sewage issues. Longtime observers find this hard to believe, but time will tell. The new attention certainly is welcome.
Another innovative partial solution could be recycled water. Water reuse of Mexican sewage can be used as irrigation source in Baja’s Guadalupe Valley’s wine growing region. This would also help solve the problem of scarce and increasingly expensive water in Baja California which only gets about 15% of Mexico’s allotment of Colorado River water
Hopefully the millions in U.S. funding and some additional Mexican funding can make significant progress solving the cross-border sewage problem. In the future when we seek the next fix of this border pollution, Americans and Mexicans might look at casting a larger net to catch funding from those businesses benefiting from prosperity on both sides of the border. Congressman Peters says the U.S. and Mexican partnership should be a business agreement, “This is what I need from you and this is what you can expect from me. Our future is bound together with Tijuana and San Diego. We have to get this right.”
Although we’re planning on a 4th edition, issues in California are not only timeless, but accelerating. Order “Water: More or Less” 2018 on Amazon Buy this edition of you want to read what 21 water experts had to say in 2018. Or wait for the new, more affordable edition, coming as soon as possible.