Navigating Water Quality Data and Beach Advisories After the LA Fires
Wildfires change the way water moves through our world. When flames tore through LA’s coast earlier this year, they left more than charred hillsides, they altered the flow of everything from ash to heavy metals straight into our ocean.
That’s why people are asking: Is it safe to get in the water? Surfers. Swimmers. Families. We all want to enjoy the coast we love, but we also want to be smart about it.
This post breaks down what we know, what the data says, and what we’re doing to keep our community informed, safe, and empowered.
So, is it safe to surf or swim right now?
Mostly yes, but pay attention.
As of now, LA County has lifted its fire-related ocean water advisories. That means testing has shown low levels of chemical contaminants that pose a risk to human health. Still, the coastline isn’t entirely in the clear.
Post-fire debris cleanup is ongoing, especially between Las Flores and Will Rogers. Nails, glass, ash-soaked building materials, these are washing up or floating just offshore.
Here’s your real-time resource list:
Even if the water looks inviting, use your judgment. Here’s what we recommend:
- Stay at least 250 yards away from any active debris removal areas.
- Avoid visibly impacted beaches, especially around the high tide line.
- Wear shoes on wet sand.
- Skip the dip if you see or smell anything off.
Safer zones? South of Montana Ave in Santa Monica and farther north in Malibu are showing fewer impacts right now.
How are decisions being made to issue fire-related ocean and beach advisories and closures?
In the weeks following the fires, LADPH issued fire-related ocean closures and advisories because ash and debris were moving from the burn zone into the ocean. Ash particles were moving in the air and settling in the ocean. Ash and larger debris were getting into storm drains and washing down to the beach. Runoff during and after rain events washed the burn zone further and moved material towards the ocean. Waves and tides even today continue to lap up onto beachfront properties that have not been cleaned up yet, pulling ash and fire debris into the ocean. This material is loaded with different types of toxic chemicals and other contaminants that can put human health and marine life at risk in the ocean. Just think of all the different products and building materials that would have been on-site in the residential and commercial properties that burned - plastics, treated lumber, paints, pesticides, cleaning chemicals, gasoline, lithium batteries - the constituents of all these materials and more tied up in the ash and debris that is being removed from the fire zone - either intentionally through clean up efforts or washing down into the ocean with air or runoff. Once there a surfer or swimmer could be exposed to these toxins through dermal exposure through the skin, inhalation of chemicals that aerosolize in the surf, or by accidental ingestion of seawater.
To protect public health from these exposures to fire-related contaminants, the LADPH issued ocean closures while plans were made to determine appropriate water quality testing programs. Unlike regular beach water quality testing programs that measure bacteria levels in the ocean to protect people from the health risks of swimming or surfing in sewage (see below section), monitoring recreational waters for fire-related pollution is an emerging concern. There aren’t any national or state-mandated protocols or end-points for this type of testing, and health standards to protect against recreational exposure at the beach are spotty at best.
The good news is that there are many health and environmental agencies and research institutions in Southern California with some experience in this realm. Early-on, Surfrider joined regional post-fire water quality monitoring efforts led by the Southern California Coastal Water Resource Project (SCCWRP) and the CA Regional Water Board to discuss the types of pollutants that should be tested in Santa Monica Bay and affected beaches, testing methodologies, and how best to communicate the results to the public.
The Water Board started pulling samples at LA area beaches at the end of January and testing them for heavy metals, nutrients, Polycyclic Aromatic Hydrocarbons (PAHs), and PFAs/PFOAs. Learn more about these types of fire-related contaminants here. The County kept their closures and advisories posted while waiting on test results (it takes a couple of weeks for all lab work to be completed). Once a couple rounds of testing results showed that contamination levels were not high enough to pose a risk to human health, the county downgraded and finally lifted their fire-related ocean advisories.
In order to interpret their test results, the State Water Board used EPA’s regional screening tool to calculate appropriate water quality criteria to be protective of human health. Their assumptions for recreational exposure were determined to protect people of all ages who might regularly spend a lot of time in the water, like surfers and lifeguards in training. Even with these prolonged exposures (up to 4 hours/day for 182 days/year) , test results have not indicated human health risks from fire-related heavy metals or chemicals dissolved in the ocean water.
While fewer results are available, initial testing of beach sand has also not shown contamination levels above background levels or health standards. View all Waterboard data here.
Why is debris still a concern?
Even if chemical levels are low, that doesn't mean there isn't any risk, though. The physical aftermath of the fires remains real:
- Sharp debris like nails and glass buried in sand
- Charred timber or synthetic fragments in the surf
- Debris stirred up by cleanup operations
We’ve heard firsthand from beachgoers who stepped on debris or spotted floating insulation near shorebreaks. The bottom line: It’s not just water quality, it’s what’s in the water.
Regular beach testing for fecal bacteria & swim advisories. What does it mean?
Regular beach monitoring programs conducted by health agencies like the LA Department of Health (LADPH) test for the presence of fecal indicator bacteria, enterococcus, and other coliform bacteria. The presence of these bacteria indicate fecal pollution (sewage or animal waste) that can get into the ocean through sewage spills, leaks, and overflows or carried down to the beach by stormwater runoff. The County samples life-guarded beaches weekly, typically on Mondays or Tuesdays. When bacteria levels exceed health standards, the chance of getting sick from exposure to pathogens in feces, or poop, goes up, and DPH will issue a swim advisory. Common illnesses include gastrointestinal symptoms; eye, ear & sinus infections; rashes, and hard-to-treat skin infections like MRSA.
The County will also issue rain advisories 72 hours after a storm event. Bacteria tests take 24 hours to give results, so these rain advisories are issued as a precaution, based on historical data that show bacteria levels and the associated health risk remain high for approximately 3 days after it rains. All advisories issued by the LADPH are posted online here.
The LA Blue Water Task Force samples 11 beaches from Surfrider Beach in Malibu down to Venice Beach every other Saturday for enterococcus bacteria, making more information available so people can decide where it is safe to get into the water to swim, surf, or play. View our results here.
Surfrider LA’s Blue Water Task Force is collecting samples every other Saturday from 11 local sites, testing for bacteria like Enterococcus (an indicator of fecal contamination). These results are posted online the next day.
What about seafood and shellfish?
Here’s where things get trickier.
While water testing shows low short-term risk for swimmers, bioaccumulation in marine life is a long-term concern. Heavy metals like mercury and lead settle into sediment and make their way up the food chain.
That’s why we’re telling folks to hold off on eating locally caught fish or shellfish from Santa Monica Bay until state advisories change.
Check the latest here:
What’s the story with algal blooms?
The recent surge in marine mammal strandings along our coastlines isn't just alarming, it's a stark indicator of the unprecedented toxic algae bloom affecting Southern California's marine life.
We’re in year four of consecutive harmful algal blooms (HABs) along SoCal’s coast, and this year’s blooms are releasing domoic acid and saxitoxin, both neurotoxins.
The fires didn’t cause this alone. HABs are fueled by:
- Warmer ocean temps
- Rain-induced nutrient loading
- Ocean upwelling and acidification
Risks for humans? Low, unless you’re eating local shellfish. Risks for marine life? High.
Track the status: Marine Biotoxin Monitoring
How do I know if the water’s safe today?
Here’s your real-time resource list:
Follow us on Instagram @surfriderla for alerts, closures, and community action.
What’s Surfrider LA doing about all this?
We’re:
- Leading biweekly testing through our Blue Water Task Force
- Partnering with scientists and agencies to expand data coverage
- Advocating for transparency and timely data releases
- Supporting volunteers and expanding access to post-fire testing data
- Working on advocacy, we are going to Sacramento and Washington, D.C.
- Expanding our water retention from urban runoff with our Ocean Friendly Garden’s program
- Educating our members and volunteers on prevention and actions we can take on a daily basis
We’re also learning from our response to the Maui fires: communication, science, and community leadership can save lives and ecosystems.
What you can do right now:
- Respect debris cleanup zones. Stay 250 yards away.
- Don’t walk barefoot near the high tide line in burned areas
- Wait 72 hours after any major rainfall before entering the ocean.
- Report debris or hazards to LA County Beaches and Harbors.
- Support nature-based solutions like bioswales, wetlands, and rain gardens.
Final Word: Stay Informed, Stay Empowered
Our coastline is healing, but it takes time.
Data shows that recreational risks are currently low in many areas, but that doesn’t mean the story’s over. We’re still learning about how fire-related pollutants behave in saltwater ecosystems, and new testing is underway.
Your judgment matters. If a beach looks sketchy, trust your gut and find a safer spot.
We’ll keep testing, sharing results, and fighting to protect LA’s coast. Because everyone deserves clean water and safe waves.
See you out there, with reef-safe sunscreen, a sharp eye on the shoreline, and the power of good science on your side.
Please direct your response to eermacora@surfriderla.org. Thank you for your prompt attention and for ensuring the ongoing protection of public and environmental health.
Sincerely,
Surfrider Foundation Los Angeles