Planes are dumping ocean water to fight the Los Angeles fires. Here's why using saltwater is typically a last resort

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Planes are dumping ocean water to fight the Los Angeles fires. Here’s why using saltwater is typically a last resort

Science Jan 13, 2025 4:39 PM EST

Firefighters battling the deadly wildfires that raced through the Los Angeles area in January 2025 have been hampered by a limited supply of freshwater. So, when the winds are calm enough, skilled pilots flying planes aptly named Super Scoopers are skimming off 1,500 gallons of seawater at a time and dumping it with high precision on the fires.

Using seawater to fight fires can sound like a simple solution – the Pacific Ocean has a seemingly endless supply of water. In emergencies like Southern California is facing, it’s often the only quick solution, though the operation can be risky amid ocean swells.

ANALYSIS: 5 ways to look at the Los Angeles fires through the lens of climate realism

But seawater also has downsides. … Saltwater corrodes firefighting equipment and may harm ecosystems, especially those like the chaparral shrublands around Los Angeles that aren’t normally exposed to seawater. Gardeners know that small amounts of salt – added, say, as fertilizer – does not harm plants, but excessive salts can stress and kill plants.

While the consequences of adding seawater to ecosystems are not yet well understood, we can gain insights on what to expect by considering the effects of sea-level rise.

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