Why Is the Ocean Pink in Santa Monica?

Published on September 12, 2025

If you’ve been strolling along Santa Monica Beach lately and noticed the waves glowing a bright pink, you’re not imagining things. Many locals and visitors have been asking: “Why is the ocean pink in Santa Monica?” The answer is simple — and exciting: it’s all part of groundbreaking research to improve ocean health and water quality.

What’s Happening?

On select mornings in September starting Monday, September 15, researchers from the UCLA Samueli School of Engineering, in collaboration with The Bay Foundation, are releasing a temporary, non-toxic fluorescent pink dye into the water near the historic Santa Monica Breakwater and Pier. This dye — called Rhodamine Water Tracer — has been safely used for decades in oceanographic studies around the world. It’s completely harmless to people, animals, and marine life. The pink plumes may look dramatic, but they disperse naturally and quickly fade.

Why Turn the Ocean Pink?

The goal of the project is to study how water circulates around the Santa Monica Pier and breakwater. For decades, water quality beneath and around the Pier has been a concern, and scientists want to better understand how currents carry pollutants, nutrients, and sediments through the Bay. By tracking the dye’s movement, researchers can map out the invisible patterns of ocean currents. As Professor Timu Gallien, the study’s lead investigator, explains, even though the old breakwater was damaged long ago, it still shapes how water flows and how healthy the surrounding ecosystem is.

A Legacy of the Breakwater

Built in 1934 to create a yacht harbor, the Santa Monica Breakwater was heavily damaged by storms and reduced in height by the mid-1980s. Though it no longer functions as a marina, it still impacts coastal hydrodynamics, protecting the beach from large waves and influencing local circulation. Understanding this influence is key to improving water quality and protecting beachgoers.

Community Science in Action

The project is not just about data — it’s also about community awareness. On release days, visitors will see:
– Neon pink waves swirling beneath the Pier
– Drones and drifters tracking the dye’s path
– Research boats with UCLA scientists at work (and maybe a surprise appearance from our beloved mascot, Inkie)
– Informational booths where researchers answer questions

A Positive Step for Ocean Health

Funded by The Bay Foundation and supported by the City of Santa Monica, the California Coastal Commission, and the U.S. Army Corps of Engineers, the experiment reflects a shared commitment to protecting Santa Monica Bay.

Tom Ford, CEO of The Bay Foundation, highlights the importance: “The findings will help guide efforts to protect and restore this vital coastal ecosystem.”

What It Means for Santa Monica

So, the next time you see the ocean glowing pink and wonder, “Why is the ocean pink in Santa Monica?”, remember: it’s not pollution or an accident — it’s science in action. These vibrant pink waves are helping researchers uncover the hidden dynamics of the Bay and paving the way for cleaner, healthier waters for everyone to enjoy.

 

Photo credit: Erik Jepsen/UC San Diego