Testing L.A.’s oceans and rivers after the 2025 wildfires
Measuring water quality post-wildfires to understand potential health and environmental risks.
USC Launched 2025
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When L.A. had questions about water safety in the wake of the 2025 wildfires, we expanded our CLEAN research to help provide answers.
Following the 2025 wildfires, some contaminants briefly increased in local waters — raising understandable concerns about safety and environmental health. To understand what’s truly happening, we’re partnering with Surfrider LA and HealTheBay to collect samples and track heavy metals, nutrients, and chemicals across beaches, rivers, and inland waterways throughout the year.
We’re working with UC Riverside to analyze our samples, and what we’ve found so far is reassuring. While a few measures rose shortly after the fires, levels declined quickly and are now all below EPA thresholds. Nutrient changes aligned with seasonal ocean upwelling rather than fire activity, and chemicals like PFOS dropped sharply after early spikes — suggesting limited, short-lived impacts rather than ongoing contamination.
Meet the project team

Max Teirstein
Project Manager
Research team

Noelle Held
Assistant Professor
USC Department of Biological Sciences, Marine and Environmental Biology

Mia Franks
PhD Candidate
USC Department of Biological Sciences, Ocean Sciences

Daniel Petras
Assistant Professor of Biochemistry
UC Riverside, Biochemistry Department
