The interactive map
Follow the Flow
Every pipe, pump, and treatment plant on both sides of the border. Choose a point to see what it does, switch seasons, and trace the problems back to their roots.
Get monthly updatesIn dry months, the river is mostly diverted when the pumps work. The bigger problem is Punta Bandera: about half of what reaches the coastal plant is dumped on the shoreline, and currents carry it north to Imperial Beach.
Figures are approximate averages drawn from public reports as of September 2026. Flows vary widely day to day and storm to storm. MGD means million gallons per day.
Everything on the map, as a list
The same information the map shows, in plain text. Figures are approximate.Figures are approximate averages drawn from public reports as of September 2026. Flows vary widely day to day and storm to storm. MGD means million gallons per day.
Pipes, pumps and plants (14)
- PB-CILA pump station
Mexico, at the river just south of the border
Pumps sewage-laden water out of the Tijuana River channel before it can cross the border. Most of what it catches is sent down the coast and discharged at Punta Bandera, not treated.
Dry season: about 15 MGD arriving against 23 MGD capacity. Storm: about 109 MGD arriving against 0 MGD capacity. Shuts off above about 23 MGD, to protect the pumps from sand and trash.
In the dry season: Pumps run and divert most of the river, when they are not broken. Dry-weather breakdowns still happen: pipe collapses in May 2026 forced shutdowns.
During a storm: Shuts off when river flow tops about 23 MGD, to protect the pumps from sand and trash. An average of about 109 MGD of sewage-contaminated water then crosses the border without treatment (EPA average, 2015-2019). That is an average: individual storms can push flows past a billion gallons a day, and the pumps stay off until the river drops back below about 23 MGD, which can take days or longer.
What's planned: No capacity increase is planned. The trash boom and upstream cleanups help keep it running.
- South Bay International Wastewater Treatment Plant
United States, next to the border
The U.S.-run plant that treats sewage piped over from Tijuana plus what the canyon collectors catch. Treated water goes out the South Bay Ocean Outfall, about 3.5 miles offshore.
Dry season: about 35 MGD arriving against 35 MGD capacity. Storm: about 38 MGD arriving against 35 MGD capacity. Capacity 35 MGD since August 2025. 25 MGD gets full secondary treatment; the extra 10 MGD added in 2025 gets advanced primary treatment and is blended before discharge.
In the dry season: Running at its limit. After the May 2026 pipe collapse it took more than 45 MGD for 13 hours, well past design capacity.
During a storm: Still capped near 35 MGD. It treats piped sewage, not the storm water running down the river.
What's planned: Rebuild to 50 MGD is underway (about $600 million). Target dates in public documents range from 2027 to 2031.
- San Antonio de los Buenos plant (Punta Bandera)
Mexico, on the coast about 5 miles south of the border
Tijuana's main coastal treatment plant. It receives roughly twice what it can treat, so about half is discharged untreated onto the shoreline, and currents carry it north.
Dry season: about 36 MGD arriving against 18 MGD capacity. Storm: about 40 MGD arriving against 18 MGD capacity. Capacity about 18 MGD.
In the dry season: The leading cause of Imperial Beach closures in dry months, according to Scripps modeling.
During a storm: Still over capacity. Storm inflow is likely higher than shown and poorly documented.
What's planned: A U.S.–Mexico working group (Minute 333) is studying an offshore outfall and expansion to about 43 MGD. Neither is funded yet.
- Pump Station 1 and the coastal conveyance
Mexico
Collects Tijuana sewage and the water PB-CILA pulls from the river, and pushes it through aging pipelines to San Antonio de los Buenos on the coast.
In the dry season: The line to the coast collapsed twice in May 2026, sending tens of millions of gallons into the river.
During a storm: Carries more flow as storm water seeps into sewers, stressing old pipes.
What's planned: Being rebuilt to pump 80 MGD, expected November 2027. Pipeline rehabilitation was completed in August 2026.
- Tijuana sewer system
Mexico
Collects wastewater from a city of more than 2 million. Leaks, broken collectors, failed pump stations, and homes without sewer connections send sewage into the river channel and canyons.
In the dry season: Roughly 75% of the network and half its pump stations need urgent repair, per a 2026 regional report.
During a storm: Storm water enters the pipes and overflows spill to the river.
What's planned: Dozens of repair projects under the 2025 U.S.–Mexico agreement, with Mexico committing about $93 million over 2026–27.
- Arturo Herrera and La Morita plants
Mexico, upstream
Two inland plants discharge treated (sometimes poorly treated) water into the river. That adds volume PB-CILA has to handle.
In the dry season: About 10 MGD of effluent flows into the river channel.
During a storm: Adds to storm flows.
What's planned: Phase 1 (about $16 million) is expected in mid-2027 and Phase 2 in December 2027. A project will divert about 10 MGD of this effluent upstream of Rodriguez Dam instead of into the river.
- Goat Canyon collector
United States, at the border
A U.S.-owned intake that catches dry-weather flows coming down Los Laureles Canyon from Tijuana and pipes them to the South Bay plant.
In the dry season: Captures canyon flows when it works. Failures at the Laureles pump stations in Tijuana send more sewage here.
During a storm: Overwhelmed or shut off, and flows run through the valley to the estuary. Sediment basins trap debris.
What's planned: Upstream trash and dumpsite cleanup in Los Laureles Canyon protects this collector.
- Smuggler's Gulch collector
United States, at the border
Catches dry-weather flows from Matadero Canyon in Tijuana and sends them to the South Bay plant.
In the dry season: Captures canyon flows when it works. Has been shut down by sediment and valve failures.
During a storm: Overwhelmed, and flows reach the river. A sediment basin and trash boom sit downstream.
What's planned: Mexico finished a sediment basin in Matadero Canyon in May 2026. A funded U.S. upgrade adds basins, culverts, and trash capture.
- Canyon del Sol, Stewart’s Drain, Silva Drain
United States, at the border (locations approximate)
Three smaller canyon collectors that work the same way: catch dry-weather flows and send them to the South Bay plant.
In the dry season: Handle small volumes. Little public data on their performance.
During a storm: Overwhelmed in storms.
What's planned: No major projects announced.
- Tijuana River trash boom
United States, just downstream of the border
A floating barrier across the river channel that traps floating trash before it reaches the estuary and clogs downstream infrastructure.
In the dry season: Little flow; crews clear debris between storms.
During a storm: Has stopped about 2,000 tons of trash over two storm seasons. It only catches what floats.
What's planned: State funding extends operations. The pilot is meant to inform a permanent structure.
- Saturn Boulevard hotspot
United States, Tijuana River Valley
Outdated road culverts churn sewage-filled river water and release hydrogen sulfide gas into nearby neighborhoods.
In the dry season: Low flows still churn through the culverts when sewage crosses.
During a storm: The heaviest flows and worst odors. Hydrogen sulfide readings here have hit thousands of times normal urban levels.
What's planned: A $2.5 million interim pipe extension is underway, with construction expected in 2027. In September 2026 the county approved $4 million to design and permit the permanent fix, estimated at about $25 million and not yet funded to build.
- Imperial Beach
United States
Where both pathways end up: the river mouth to the south, and the plume from Punta Bandera carried north along the coast.
In the dry season: Closures driven mainly by the Punta Bandera plume.
During a storm: Closures driven mainly by river flows through the estuary, plus the plume.
What's planned: The beach has been closed for most of the past several years.
- South Bay Ocean Outfall
Pacific Ocean, about 3.5 miles offshore
Carries treated water from the South Bay plant far enough offshore to avoid the beach.
In the dry season: Discharges treated effluent.
During a storm: Discharges treated effluent.
What's planned: No change planned.
- Proposed U.S. river diversion and treatment (proposed)
United States (site not yet chosen)
The only project aimed at storm flows: capture river water on the U.S. side and treat it before it reaches the estuary.
In the dry season: Would capture dry-weather crossings when PB-CILA fails.
During a storm: Would treat part of the storm flow that now crosses untreated.
What's planned: San Diego County approved $1.8 million for design. Construction depends on a November 2026 sales tax measure.
What reaches the ocean (4)
- Tijuana River mouth
Estuary, south end of Imperial Beach
About 1 MGD in the dry season, 109 MGD in a storm, untreated.
Dry season: A minor source when pumps work; spikes when PB-CILA or pipes fail.
Storms: About two-thirds of the pollution behind rainy-season beach closures, per Scripps modeling.
What it carries: Raw sewage, Industrial chemicals, Trash, Sediment.
More than 200 billion gallons of sewage-contaminated water have crossed the border in the Tijuana River since October 2018, according to IBWC figures cited by the California State Assembly.
- Punta Bandera shoreline
Mexico, about 5 miles south of the border
About 18 MGD in the dry season, 22 MGD in a storm, untreated.
Dry season: The dominant source behind dry-season beach closures, per Scripps modeling. Currents carry the plume north.
Storms: About one-third of rainy-season closure pollution.
What it carries: Raw sewage, Partly treated sewage, Industrial chemicals.
About 18 MGD (2025-2026 reporting, after the plant's rebuild), which is on the order of 6 to 7 billion gallons of untreated sewage a year — our estimate from published daily figures, not an official total. You may see a larger number elsewhere: EPA's watershed page says about 50 MGD flows out of San Antonio de los Buenos Creek. That is an older figure for total flow, from before the plant was rebuilt in 2025. Our 18 MGD estimates only the untreated share today: the rebuilt plant treats about 18 MGD, roughly half of what it receives.
- Border canyons
Goat Canyon and Smuggler’s Gulch into the estuary
About 0.5 MGD in the dry season, 8 MGD in a storm, untreated, poorly documented.
Dry season: Mostly captured by the collectors when they work.
Storms: Collectors are overwhelmed and flows reach the estuary. Volumes are poorly documented.
What it carries: Raw sewage, Trash, Sediment.
Spills spike when Tijuana pump stations like Los Laureles fail.
- South Bay Ocean Outfall
About 3.5 miles offshore
About 35 MGD in the dry season, 38 MGD in a storm, treated.
Dry season: Treated water discharged far offshore; not a major driver of beach closures.
Storms: Same. The plant treats piped sewage, not river storm flow.
What it carries: Treated wastewater from the South Bay plant and a City of San Diego reclamation plant.
This is what the system looks like when it works: sewage captured, treated, and released far from shore. The South Bay plant's discharge has been under a state cease and desist order since 2025 over permit violations.
Layer 1: At the coast (3 problems)
This is what people in the South Bay experience. Every one of these is a symptom of something further upstream.
- Beach closures at Imperial Beach What people experience
The beach has been closed for most of the past several years. It is fed by two pathways: the river mouth and the Punta Bandera plume.
Where it stands: Depends on fixing the layers behind it.
Ways to help: Beach cleanups in Imperial Beach; Protect yourself from polluted air and water.
- Hydrogen sulfide in the air Funded or underway
Sewage churning through old culverts at Saturn Boulevard releases toxic gas into nearby neighborhoods.
Where it stands: A $2.5 million interim pipe extension is underway, with construction expected in 2027. In September 2026 the county approved $4 million to design and permit the permanent fix. The permanent fix, about $25 million, is not funded.
Being tried: Ozone nanobubble treatment in the river; Saturn Boulevard culvert redesign; Hydrogen sulfide monitoring; Free home air purifiers (AIRE program).
Ways to help: Pre-storm sweep in the river valley; Protect yourself from polluted air and water; Speak at County Board of Supervisors meetings.
- Contaminated estuary What people experience
Sewage, chemicals, and trash settle in the Tijuana River Estuary, a protected wetland.
Where it stands: Depends on stopping river crossings.
Being tried: Ozone nanobubble treatment in the river; Floating trash boom in the main channel.
Ways to help: Pre-storm sweep in the river valley; Pre-storm sweep near the border; San Diego Coastkeeper: water testing and legal pressure; Tijuana Estuary Foundation; San Diego Foundation: Binational Resilience Initiative.
Layer 2: At the border (5 problems)
At the border, the problem is capacity: the plants and pumps are too small or too fragile for what arrives, especially in storms.
- Nothing handles storm flows Proposed, not funded
In storms, an average of about 109 MGD of sewage-contaminated water crosses the border without treatment (EPA average, 2015-2019). That is an average: individual storms can push river flows past a billion gallons a day, roughly ten times higher, and the pumps stay off until flows drop back below about 23 MGD, which can take days or longer. No existing or funded facility is sized for them.
Where it stands: San Diego County is designing a U.S.-side diversion and treatment system ($1.8 million, approved 4-1 on September 1, 2026). Construction depends on a November 2026 sales tax measure.
Being tried: Advanced treatment for a U.S. river diversion.
Ways to help: Learn about the November sales tax measure.
- PB-CILA shuts off in storms and clogs No plan yet
The river diversion stops above about 23 MGD, and trash and sediment damage it. It has also broken down in dry weather.
Where it stands: No capacity increase planned. Trash capture upstream helps keep it running.
Being tried: Floating trash boom in the main channel.
Ways to help: Source cleanups in Camino Verde; Citizens for Coastal Conservancy.
- South Bay plant at capacity Funded or underway
The U.S. plant runs at its 35 MGD limit and gets pushed past it when Mexican pipes fail.
Where it stands: Rebuild to 50 MGD underway, about $600 million. The first major construction contract was awarded in September 2026. Target dates range from 2027 to 2031.
Ways to help: Surfrider: Clean Border Water Now; Ask Congress and the EPA to fund upkeep, not just construction.
- Canyon collectors clog and overflow Funded or underway
Sediment and trash shut the collectors down, and storms overwhelm them.
Where it stands: Smuggler's Gulch upgrade is funded and in design. Goat Canyon basins are maintained by State Parks.
Being tried: Trash boom and paid collection in Los Laureles Canyon.
Ways to help: Source cleanups in Los Laureles Canyon; Source cleanups in Matadero Canyon; WILDCOAST: canyon trash boom and paid collectors.
- Trash reaching the valley Funded or underway
Tires, plastics, and debris clog pumps and culverts and pile up in the estuary.
Where it stands: The trash boom has stopped about 2,000 tons over two storm seasons and is funded through 2026–27. It only catches floating trash.
Being tried: Floating trash boom in the main channel.
Ways to help: Pre-storm sweep in the river valley; Pre-storm sweep near the border; Source cleanups in Camino Verde; Help tally what the trash boom catches; Alter Terra: Tijuana River watershed projects; Speak at County Board of Supervisors meetings.
Layer 3: In Tijuana's system (9 problems)
Inside Tijuana, sewage escapes from broken pipes and failing pumps, and trash from canyon dumpsites clogs the equipment downstream.
- Half of Punta Bandera’s inflow dumped untreated Proposed, not funded
The coastal plant treats about 18 MGD but receives roughly twice that. The rest goes onto the shoreline.
Where it stands: A U.S.–Mexico group is studying an offshore outfall and expansion to about 43 MGD. Not funded.
- Too little treatment capacity for growth Funded or underway
Tijuana's plants haven't kept pace with the city.
Where it stands: Mexico committed to a new 3 MGD Tecolote–La Gloria plant by December 2028.
- Pipes to the coast keep collapsing Done
The aging line to Punta Bandera collapsed twice in May 2026, sending tens of millions of gallons into the river.
Where it stands: Rehabilitation was completed in August 2026, EPA says.
- Pump Station 1 undersized and failing Funded or underway
Tijuana's main pump station can't move enough sewage reliably.
Where it stands: Rebuild to 80 MGD pumping, expected November 2027.
- Treated effluent adds volume to the river Funded or underway
Two upstream plants discharge about 10 MGD into the river channel.
Where it stands: Project to divert it upstream of Rodriguez Dam. Phase 1 (about $16 million) is expected in mid-2027, and Phase 2 in December 2027.
- Sewage leaking into the river channel Funded or underway
Sewer connections spill directly into the concrete river channel in Tijuana.
Where it stands: The Tijuana River Gates project will keep at least 5 MGD out of the river, expected early 2027.
- Los Laureles pump stations fail Funded or underway
When they break, sewage flows down Los Laureles Canyon to the Goat Canyon collector.
Where it stands: Mexico has committed funds to rehabilitate the Laureles PB-2 pump station, part of its 2026 funding commitment. Construction is expected to start in December 2026 (EPA update, September 2026).
- Illegal dumpsites in the canyons No plan yet
More than 1,000 dumpsites in Tijuana canyons feed trash to the collectors, pumps, and river. Los Laureles, Matadero, and Camino Verde are known hotspots.
Where it stands: Only small nonprofit efforts, like paid resident collection in Los Laureles. No citywide plan.
Being tried: Trash boom and paid collection in Los Laureles Canyon.
Ways to help: Source cleanups in Los Laureles Canyon; Source cleanups in Matadero Canyon; Source cleanups in Camino Verde; Help tally what the trash boom catches; Map dumpsites with local partners; WILDCOAST: canyon trash boom and paid collectors; Alter Terra: Tijuana River watershed projects; San Diego Foundation: Binational Resilience Initiative.
- Sediment from Matadero Canyon Done
Sediment washing down Matadero Canyon clogged the Smuggler's Gulch collector.
Where it stands: Mexico finished a sediment basin in May 2026.
Ways to help: Source cleanups in Matadero Canyon.
Layer 4: Root causes (6 problems)
Underneath it all: a city that outgrew its system, too little money for upkeep, no controls on industrial waste, and gaps in trash collection.
- City outgrew its system Proposed, not funded
Tijuana has grown to a metro area of more than 2 million people, with informal settlements built without sewer or trash service.
Where it stands: Minute 333 sets up planning for future growth. Largely at the study stage.
- Too little money for maintenance Proposed, not funded
Past fixes failed because upkeep went unfunded. Rising electricity costs strain the utility’s budget.
Where it stands: A maintenance account at the North American Development Bank is proposed; recommendations are due by December 2026.
Ways to help: Surfrider: Clean Border Water Now; Ask Congress and the EPA to fund upkeep, not just construction.
- Aging network needs repair Funded or underway
About 75% of Tijuana's sewer network and half its pump stations need urgent repair.
Where it stands: Mexico committed about $93 million for 2026–27. Only part of the need.
- Industrial chemicals in the sewage No plan yet
Enforcement of the rules on industrial waste appears weak, and standard treatment cannot remove some of the chemicals that reach the sewers.
Where it stands: No plan. A complaint to the Commission for Environmental Cooperation was accepted for review in 2026, and Mexico was given until 28 August 2026 to respond.
Ways to help: San Diego Coastkeeper: water testing and legal pressure; Press for accountability on industrial waste.
- Gaps in trash collection No plan yet
Irregular or pay-per-pickup trash service in canyon neighborhoods drives illegal dumping.
Where it stands: No citywide plan.
Being tried: Trash boom and paid collection in Los Laureles Canyon.
Ways to help: Map dumpsites with local partners; WILDCOAST: canyon trash boom and paid collectors; Speak at County Board of Supervisors meetings; Ask Congress and the EPA to fund upkeep, not just construction.
- Agreements depend on funding Status unclear
The U.S.–Mexico agreements are conditional on money being available, and the U.S. cannot compel action in Mexico.
Where it stands: The U.S. ties funding to Mexico meeting milestones. Mexico’s response to the environmental complaint was due August 2026.
Ways to help: San Diego Coastkeeper: water testing and legal pressure; Surfrider: Clean Border Water Now; Ask Congress and the EPA to fund upkeep, not just construction; Press for accountability on industrial waste.
Technology trials (7)
- Ozone nanobubble treatment in the river
Stopped early. USIBWC with contractor Greenwater Services. September 9 to October 15, 2025. Cost: Reported at $1.1 million by the company; local reporting cites a $2.5 million contract.
Four floating units injected tiny ozone-filled bubbles into the river just downstream of the border, to kill bacteria and cut the odors that come from sewage.
- 91.5% — average drop in total coliform near the units on treatment days (company-reported, 10 samples)
- 83.8% — cumulative drop in E. coli near the units (company-reported)
What worked: Bacteria dropped sharply on treatment days, and U.S. Customs and Border Protection staff near the site reported less odor.
Where it struggled:
- Planned to run around the clock for about 60 days, it lasted 36 days and ran only in daytime for 22 of them.
- Trash clogged the intake and nozzles during nighttime surges from Mexico, so the units could only run in daytime.
- Operations paused for a flood warning in September and again to install a trash boom.
- On October 14, a storm surge flooded the site overnight, damaging the units, generators, and fuel cells and causing a small diesel spill. The pilot ended there.
- Even after treatment, bacteria stayed far above standards for human contact.
Lesson: The chemistry worked; the river setting did not. The contractor estimates about 40 units, debris filtering, and round-the-clock operation would be needed at scale. The IBWC called it successful but said major design changes are needed; a county supervisor called it a failure.
Sources: USIBWC, ozone pilot project report, December 2025, The Coronado News, what happened during the ozone pilot, February 2026
- Floating trash boom in the main channel
Running, funded through 2026–27. Alter Terra and the Rural Community Assistance Corporation, funded by the State Water Board. Installed November 2024 for two storm seasons, now extended. Cost: $4.7 million, plus $2 million approved in July 2026.
Interlocking floating modules made partly of recycled plastic span the river. Water passes underneath while floating trash is held back.
- 2,000 tons — of trash and debris stopped over two storm seasons
- 80–100 tons — arrived in hours in one storm without breaching it
What worked: It held up under large storm surges and kept tons of trash out of the valley and estuary.
Where it struggled:
- It only stops floating debris. Sewage, dissolved contaminants and sediment pass through.
- It cannot be cleared during storms, when debris is heaviest, because rising water makes it unsafe for crews.
- Hauling debris to the landfill is the main ongoing cost.
- State contracts run through 2027, but the money is projected to run out at the end of the 2026–27 season.
Lesson: Simple, rugged designs survive this river. The pilot is meant to inform a permanent structure.
Sources: State Water Board, trash booms funding extension, July 2026, Border Report, rising water levels stop crews removing debris from the trash boom, RCAC, Tijuana trash boom passes 1,000 tons, February 2026, RCAC, Imperial Beach project profile, 2026
- Trash boom and paid collection in Los Laureles Canyon
Running. WILDCOAST and Tijuana residents. Since January 2021; a second boom added in Matadero Canyon in October 2024. Cost: Grant funded.
The first trash boom in Mexico, paired with a network of residents paid per kilogram of plastic collected before it reaches the creek.
- 239,000+ lbs — of waste caught between 2021 and 2024
- About 93% — of captured waste was plastic and tires, in the first year
What worked: Stops trash close to its source and builds local support by paying residents.
Where it struggled:
- Small scale compared with the number of canyons and dumpsites.
- Depends on continued grant funding.
Lesson: Source capture works best when it pays the community doing the work.
Sources: WILDCOAST, Los Laureles trash boom, 2022, The Inertia, on the tsunami of trash at the border, and residents paid by the kilogram, KPBS, WILDCOAST installs a second trash boom, October 2024
- Saturn Boulevard culvert redesign
Interim fix underway; permanent fix in design. San Diego County. Interim pipe extension underway, construction expected 2027; permanent fix in design. Cost: $2.5 million interim; $4 million for design and permitting; about $25 million to build the permanent fix.
Culvert extensions would carry low flows under the road and release them below the water surface, so sewage stops churning and releasing gas.
- 4,500 ppb — peak hydrogen sulfide nearby, against a 30 ppb state standard
What worked: Grounded in research: when a sudden diversion cut nighttime flows, odor reports dropped sharply, pointing to the turbulence here as the main source.
Where it struggled:
- Construction of the permanent fix is not yet funded.
Lesson: Some of the biggest air-quality gains may come from plain engineering at one hotspot, not new technology.
Sources: Science, heavily polluted Tijuana River drives a regional air quality crisis — the source for the 4,500 ppb reading, The Spokesman-Review, county greenlights the Saturn Boulevard plan, September 2026, CalMatters, the Saturn Boulevard fix, May 2026
- Hydrogen sulfide monitoring
Running. San Diego County Air Pollution Control District and Scripps researchers. Ongoing. Cost: Public agency and research funding.
A network of continuous air monitors in southern San Diego, plus research measurements that traced where the gas comes from.
- 5 to 14 hours a day — above the state standard near Berry Elementary in Nestor, September 1-10, 2024 (UC San Diego study)
What worked: Pinpointed the Saturn Boulevard hotspot as the main source and confirmed long-dismissed community reports.
Where it struggled:
- Monitoring measures the problem; it does not reduce it.
Lesson: Good data turned complaints into a targeted fix.
Sources: San Diego County News Center, public health guidance on hydrogen sulfide, June 2026, Scripps Institution of Oceanography, the Tijuana River's toxic water pollutes the air
- Free home air purifiers (AIRE program)
Running. San Diego County Air Pollution Control District. Since February 2025. Cost: State incentive funds at launch, expanded with $4 million in county funds in July 2026.
Up to three free air purifiers, with replacement filters, for households in Imperial Beach, Nestor, San Ysidro, Egger Highlands, Otay Mesa West, and the Tijuana River Valley.
What worked: Immediate indoor relief for residents.
Where it struggled:
- Only protects indoor air, and only where the units run.
- Does nothing about the source.
Lesson: A stopgap while infrastructure catches up.
Sources: San Diego County Air Pollution Control District, AIRE program, California Air Resources Board, verified air cleaners
- Advanced treatment for a U.S. river diversion
Proposed. San Diego County. In early study (about 18 months from September 2026); construction depends on the November 2026 sales tax measure. Cost: Bonds of roughly $700 million to $1 billion under discussion.
Treatment for captured river water could use ultrafiltration membranes, reverse osmosis, advanced oxidation, and UV disinfection.
What worked: Proven technologies in other settings, and the only approach aimed at storm flows.
Risks:
- Not yet tested here. Membranes are sensitive to the trash and sediment that wrecked the ozone pilot.
- High energy and maintenance costs.
- Storm flows are several times larger than any plant is sized for.
Lesson: Lessons from the ozone pilot apply: screen debris first, and design for sudden surges.
Sources: CalMatters, the county river diversion plan and the sales tax measure, September 2026
Hands-on cleanup (6)
- Pre-storm sweep in the river valley
Tijuana River Valley Regional Park, from the Monument Road trailhead. Best window: September and October, before the first rain. Again in late spring.
Not organized yet. Not organized yet. This is an idea at this stage, not a scheduled cleanup. We are working out how to run these safely and with the right permissions, and will announce dates here when we do. Get told when it is.
Clear plastics and light debris from dry banks and terraces so the next storm cannot carry them into the Saturn Boulevard culverts and the estuary. GPS-tag tires, appliances, and mattresses so county crews can remove them.
How to get involved: Coordinate with County Parks for permission, habitat timing, and bag pickup. The Tijuana River estuary reserve also runs volunteer cleanups.
Safety: Dry ground only, away from the channel and standing water. Gloves, grabbers, closed shoes. Skip days after storms or spills.
- Pre-storm sweep near the border
Regional park near Dairy Mart Road, just downstream of the trash boom. September and October, before the first rain.
Not organized yet. Not organized yet. This is an idea at this stage, not a scheduled cleanup. We are working out how to run these safely and with the right permissions, and will announce dates here when we do. Get told when it is.
Debris that slips past the boom or washes onto the banks here is the first to move in the next storm. Clearing it keeps it out of the valley and the estuary.
How to get involved: Coordinate with County Parks. Near the border, confirm which land is county-managed; the strip at the border fence is federal and closed.
Safety: Dry ground only. Check air quality alerts for hydrogen sulfide before going.
- Source cleanups in Los Laureles Canyon
Tijuana. The canyon drains into the Goat Canyon collector.. Dry season, ahead of the rains.
Dumpsites around neighborhoods like San Bernardo and El Mirador feed trash and sediment straight to the border. Removing it here protects the collector downstream.
How to get involved: Work through WILDCOAST, which runs a paid resident collection program in the canyon. Join binational cleanup days or help fund local collectors. Don’t organize independently: local partners know the sites and the community.
Safety: Go only with local partners.
- Source cleanups in Matadero Canyon
Tijuana. Drains to the Smuggler's Gulch collector.. Dry season.
Trash and sediment from Matadero Canyon clog the Smuggler's Gulch collector. Mexico just finished a sediment basin here; keeping trash out of it keeps it working.
How to get involved: WILDCOAST has run a trash boom in Matadero Canyon since October 2024 and hires residents to collect and sort what it catches. Connect through WILDCOAST or Alter Terra, both of which work in these canyons.
Safety: Go only with local partners.
WILDCOAST, trash booms · KPBS, WILDCOAST installs a second trash boom, October 2024
- Source cleanups in Camino Verde
Tijuana. Drains toward the main river channel. Location on this map is approximate.. Dry season.
Trash from here travels down the river to PB-CILA and the trash boom. Less trash means fewer pump shutdowns.
How to get involved: WILDCOAST announced plans in 2023 for a trash boom in Camino Verde, but its second boom went to Matadero Canyon instead. Ask WILDCOAST whether Camino Verde work is active and how volunteers or donors can help.
Safety: Go only with local partners.
WILDCOAST, trash booms · KPBS, WILDCOAST's nets catch trash on the river, January 2023 · KPBS, the second boom goes to Matadero Canyon, October 2024
- Beach cleanups in Imperial Beach
Imperial Beach shoreline. Year-round, avoiding days after spills.
Removes debris washed ashore. Less direct help to infrastructure than upstream work, but a good way to build a volunteer base.
How to get involved: Surfrider San Diego and other groups run regular cleanups.
Safety: Stay out of the water; check beach status first.
Donate to a project (7)
- WILDCOAST: canyon trash boom and paid collectors
Los Laureles Canyon, Tijuana. Ongoing.
Supports the trash boom in Los Laureles Canyon and a network of residents paid per kilogram of plastic collected before it reaches the creek. Stops trash at the source, upstream of the Goat Canyon collector.
How to get involved: Give through the trash boom campaign page or WILDCOAST’s general donation page. The campaign page hasn’t been updated recently, so it’s worth confirming with WILDCOAST that it’s current.
- Alter Terra: Tijuana River watershed projects
Tijuana River Valley and Tijuana canyons. Ongoing.
The binational nonprofit whose director designed the main river trash boom, with decades of work in Los Laureles Canyon. Donations support its broader watershed and community projects; the boom itself runs on a state grant, extended with $2 million through the 2026–27 storm season.
How to get involved: In the U.S., Alter Terra is a project of Earth Island Institute, which accepts donations on its behalf.
- San Diego Coastkeeper: water testing and legal pressure
San Diego and Tijuana. Ongoing.
Runs binational water quality monitoring with partners in Tijuana, and uses legal action. In 2026 it filed a complaint with the Commission for Environmental Cooperation over Mexico’s enforcement of its own environmental laws; the commission accepted it for review, and Mexico responded on September 9, 2026. The commission's staff is now considering whether to recommend a full investigation, called a factual record. The United States withdrew from the commission in January 2026, but the complaint process continues under the U.S.–Mexico–Canada trade agreement.
How to get involved: Donate through Coastkeeper’s website.
San Diego Coastkeeper · Commission for Environmental Cooperation, the Tijuana wastewater management submission · San Diego Water Board, on the U.S. withdrawal from the commission in January 2026
- Surfrider: Clean Border Water Now
San Diego region. Ongoing.
Surfrider’s San Diego program co-leads a coalition of more than 50 organizations and agencies and pushes for state and federal funding. Surfrider says it and its partners helped secure about $490 million for border water infrastructure in 2024.
How to get involved: Give to the program or join its advocacy campaigns.
- Tijuana Estuary Foundation
Tijuana River Estuary. Ongoing.
The nonprofit arm of the Tijuana River National Estuarine Research Reserve, working since 1979 to protect the estuary, one of Southern California’s largest remaining coastal wetlands. It opened a nonprofit fund at the San Diego Foundation in 2025.
How to get involved: Donate on the foundation's website.
Donate to the Tijuana Estuary Foundation · Tijuana Estuary Foundation · About the foundation (San Diego Foundation)
- San Diego Foundation: Binational Resilience Initiative
Both sides of the border. Grants awarded yearly.
Pools donations into grants for groups on both sides of the border working on water quality monitoring, watershed restoration, and community projects. In September 2026 it announced $983,439 for 10 projects involving 21 nonprofits, bringing its total since 2022 to more than $4.5 million.
How to get involved: Give to the initiative through the San Diego Foundation.
Give to the Binational Resilience Initiative · 2026 grants announcement
- Citizens for Coastal Conservancy
Imperial Beach. Ongoing.
A local nonprofit advocating that the PB-CILA pumps run around the clock. It says that would cut transboundary sewage by 78%, a figure that is the group’s own and hasn’t been independently evaluated. The pumps currently shut off in storms to avoid damage from sand and trash.
How to get involved: Donate through the group’s website.
Collect data (2)
- Help tally what the trash boom catches
The trash boom, just north of the border. After storms, once crews have pulled debris.
Sorting and counting captured debris by type and brand shows where it comes from, which points upstream cleanups at the right canyons.
How to get involved: Ask the boom’s operators, Alter Terra and the Rural Community Assistance Corporation, whether they use volunteer sorting or tally days.
Safety: Captured debris is contaminated. Follow the operator’s safety rules.
- Map dumpsites with local partners
Tijuana canyons that drain to the border. Any time in the dry season.
After a trash-tracking study in Los Laureles Canyon, Tijuana removed 171 dumpsites in 2011. An updated inventory gives officials and funders a target list.
How to get involved: Offer help to WILDCOAST, Alter Terra, or researchers at SDSU or El Colegio de la Frontera Norte. GPS photos from a phone are enough.
Safety: Go only with local partners.
WILDCOAST, trash booms · San Diego Water Board, on the 171 dumpsites removed in 2011
Speak up (4)
- Learn about the November sales tax measure
San Diego County ballot, November 3, 2026. Before Election Day.
The measure, Measure B (the San Diego County Health & Safety Act), is a half-cent county sales tax projected to raise about $360 million a year, with about $80 million a year earmarked for Tijuana River improvements. Board of Supervisors chair Terra Lawson-Remer has said that revenue could back $700 million to $1 billion in bonds to build sewage treatment for the river. The San Diego County Taxpayers Association opposes it, pointing to the tax having no end date, no yearly performance targets, and an oversight committee without a taxpayer-advocate seat.
How to get involved: Read the measure and the county’s plan, and weigh the arguments on both sides.
San Diego Foundation, nonpartisan voter education on Measure B · CalMatters on the county plan · San Diego County Taxpayers Association, November 2026 positions, August 2026
- Speak at County Board of Supervisors meetings
San Diego County. When river funding is on the agenda.
Public comment shapes how local river money is spent, for example on the full Saturn Boulevard fix, permanent trash capture, or cross-border trash programs.
How to get involved: Watch agendas and submit written or in-person comments.
- Ask Congress and the EPA to fund upkeep, not just construction
Federal representatives and agencies. Ongoing.
Past fixes failed when maintenance went unfunded. Push for a durable maintenance account, the South Bay plant’s 50 MGD timeline, and adding trash to the binational agreements.
How to get involved: Contact your representatives and senators; follow EPA and IBWC quarterly updates.
- Press for accountability on industrial waste
U.S. companies with plants in Tijuana. Ongoing.
Enforcement of the rules on industrial waste appears weak: a September 2026 San Diego Coastkeeper report found a steady stream of industrial chemicals, heavy metals and pesticides in the river, and standard treatment cannot remove some of them. U.S.-owned manufacturers can be asked to audit how their subcontractors dispose of waste.
How to get involved: Follow San Diego Coastkeeper’s complaint to the Commission for Environmental Cooperation, and support its water testing.
San Diego Coastkeeper · KPBS, on the Coastkeeper industrial chemicals report, September 2026
Stay safe (1)
- Protect yourself from polluted air and water
South Bay neighborhoods near the river. Especially during and after storms.
Check beach water status before going in the ocean, and watch county air quality alerts for hydrogen sulfide.
How to get involved: Use the county’s beach water quality site. The county air district’s AIRE program is taking applications for up to three free air purifiers in eligible South Bay neighborhoods, including Imperial Beach. It may close early if supplies run out.
County beach water quality · County air district, free air purifiers (AIRE)
What the statuses mean
- What people experience
2 problems on the map carry this status.
- No plan yet
4 problems on the map carry this status.
- Proposed, not funded
4 problems on the map carry this status.
- Funded or underway
10 problems on the map carry this status.
- Done
2 problems on the map carry this status.
- Status unclear
1 problems on the map carry this status.