California’s Imperial Beach Rated One of the Top Most Polluted Beaches in U.S.: 100% High Bacteria Rate Score

By: Lauren Fokas | Published: Jun 25, 2024

 A recent study of California’s many beaches shows that several of these picturesque locations are actually full of dangerous bacteria. In fact, some of the beaches have a 100% bacteria score.

The California beach with the highest bacteria level, a whopping 100%, is none other than San Diego’s Imperial Beach. The reason why this beach is so infested with bacteria is quite clear, but local residents are desperate for the local government to finally do something about it.

Surfrider Foundation Tested Thousands of Water Samples

The Surfrider Foundation is a global grassroots non-profit environmental organization that works tirelessly to protect the world’s oceans and beaches. Through studies, educational programs, and hands-on action, Surfrider Foundation does everything it can to ensure the planet’s oceans are well taken care of.

A promotional photograph provided by the Surfrider Foundation with the text “The ocean needs more friends”

Source: @Surfrider Foundation/YouTube

When the Surfrider Foundation released its 2023 Clean Water Report, the organization and the United States as a whole was shocked by its findings. It noted that our nation’s beaches are not nearly as clean as we might have thought.

64% of Beaches Failed to Meet Health Standards

After collecting “9,538 water samples collected from 567 distinct sampling sites,” the Surfrider Foundation reported that 64% of beaches in the USA failed to meet state health standards.

A scientist wearing protective gear tests beach water

Source: Freepik

Members of the Surfider team tested the water along beaches all down the West and East coasts, as well as in Florida, Texas, and Hawaii. And they reported that “362 of the 567 beaches and sampling sites tested yielded at least one high bacteria result that exceeded state health standards.”

Several US Beaches Contain a More than 50% Bacteria Rate

After testing the water at dozens of beaches, the Surfrider Foundation noted that several locations had more than a 50% bacteria rate.

A map of the US provided by the Surfrider Foundation, showing the beaches they tested with black dots

Source: Surfrider Foundation

Park View Kayak Launch in Miami Beach, Florida, came back with 73%, Linda Mar Beach in Pacific, California, showed 54%, and Kahalu’u Beach in Oahu, Hawaii reported a whopping 86% bacteria rate.

Imperial Beach Has a 100% Bacteria Rate Score

While these numbers were certainly concerning, there was one beach that absolutely shocked the organization. Imperial Beach in San Diego, California, reported an almost unbelievable 100% bacteria rate.

A photograph of a fence separating the Mexico and US side of Imperial Beach in San Diego, California

Source: Andrew Holbrooke/Corbis/Getty Images

However, as surprised as they were, the Surfrider Foundation team does understand why this beach in particular has such a high bacteria rate.

Why Does Imperial Beach Have a 100% Bacteria Rate?

Imperial Beach’s geographic location has made it incredibly susceptible to pollution; the beach sits directly on the border between the United State and Mexico.

A sign for the Mexico-US border in a field

Source: iStock

That means it receives cross-border sewage water from both countries. The water runoff from the Tijuana River Watershed, which spans the border, is directly causing the extreme number of bacteria within the shallow waters.


The Tijuana River Watershed

The Tijuana River Watershed is a drainage basin that covers an incredible 1,750 square miles across the US and Mexico border.

A map of the Tijuana River Watershed across the Mexico-US border


The giant watershed collects rain, snow melt, urban runoff, and agricultural runoff across the nearly 2,000 miles it covers before releasing that water back into the Pacific Ocean.


The Collected Water Flows Directly Into Imperial Beach

Sadly, for residents and visitors of San Diego’s Imperial Beach, the runoff from the watershed flows directly into the ocean next to the beautiful beach.

Rusted sewage pipes release water into the ocean

Source: Freepik

As the Surfider report explained, “This complex and beautiful region … has been plagued with severe pollution for decades. Every day, millions of gallons of contaminated water carrying stormwater runoff, raw sewage, harmful chemicals, and trash traverse the U.S.-Mexico border through the Tijuana River Watershed and flows out into the Pacific Ocean in Imperial Beach.”


California’s Recent Storms Have Intensified the Bacteria Problem

While there has always been water pollution within the water released by the Tijuana River Watershed, the recent storms in California have significantly intensified the problem.

A photograph of large dirty waves in the ocean during a storm

Source: Freepik

The extreme precipitation throughout the state, believed to be caused by climate change, has caused intense flooding which has washed an excess amount of dangerous pollutants into California’s creeks and rivers that lead to the state’s oceans.


How Does Bacteria at the Beach Affect California Residents?

Because of the extreme amount of bacteria in some of California’s most beautiful beaches, many are now closed to visitors. But even those that are still open pose a threat to California residents and tourists alike.

A close-up photograph of crystal clear and clean water on the sand

Source: Freepik

According to the NOAA, bacteria in the water “can cause gastrointestinal illness in those who swim directly in the water,” as well as other infectious diseases.


San Diego Residents Are Desperate for Government Intervention

Residents in San Diego are desperate for their local and state government to take action and finally solve the ongoing bacteria crisis.

The logo for the California Department of Public Health

Source: Wikipedia

As the Surfider report explained, “This public health and environmental justice emergency has been going on for decades and it’s only getting worse, especially with climate change-related storm events further stressing the already inadequate and failing regional wastewater infrastructure.”


California Residents Deserve Clean Beaches

Surfirder and other non-profit organizations are doing their best to educate California residents on the dangers of bacteria, but they cannot do much to actually clean up the state’s beaches without government intervention.

A photograph of an empty beach as the sun sets

Source: Freepik

Hopefully, as more and more California beaches close, residents will finally find their voice and vote for local leaders who will actually take action. Otherwise, the next generation of California residents may never be able to swim in their beautiful beaches.