Summer is almost here, and throngs of sun-seekers will soon be heading to sandy beaches for some R&R. But before you pack your towel and sunscreen, take note: some of the country’s most stunning beaches are hiding a dirty secret—literally.
RECOMMENDED: This is the number one beach in the U.S. for 2025, says Dr. Beach
According to the Surfrider Foundation’s 2024 Clean Water Report, beachgoers may be swimming in water contaminated with unsafe levels of bacteria. The report ranks the most bacteria-laden beaches, and the biggest offender is Kahalu'u Beach in Oahu, Hawaii, where a jaw-dropping 92-percent of water samples failed to meet health standards. Right behind it is Waikomo Stream at Koloa Landing in Poipu, Hawaii, with a 90-percent failure rate.
And it's not just Hawaii. The report lists top bacteria hot spots all across the U.S.—from the East and West Coasts to Puerto Rico. These aren’t remote, forgotten beaches. They’re community hubs, tourist magnets and vital ecosystems.
The foundation points to a nasty brew of stormwater runoff, sewage overflows, agricultural waste and failing infrastructure as the primary culprits for bacterial buildup. Nearly 10 trillion gallons of untreated stormwater runoff hit U.S. waterways each year. Add in 900 billion gallons of untreated sewage from aging systems, and it’s a health hazard in the making.
These beaches may look pristine, but the detected bacteria can cause rashes, stomach bugs, skin infections or worse. Raw sewage also feeds harmful algal blooms, kills fish and devastates coral reefs. Climate change only fuels the mess with rising seas and more intense storms overwhelming fragile systems.
In 2024, Surfrider’s Blue Water Task Force processed over 10,000 samples from 604 sites, with a shocking 80% showing high bacteria levels. Volunteers test water and trace pollutants, but they can’t fix the root problems alone. That’s why Surfrider is calling on Congress to stop slashing EPA funding and instead invest in clean water and resilient infrastructure. Clean, swimmable beaches shouldn’t be a luxury—they should be a given.
U.S. beaches with the highest levels of bacteria
- Waikomo Stream at Koloa Landing, Kauai, HI
- Kahalu'u, Kahalu'u, O'ahu, HI
- Imperial Beach - San Diego, CA
- San Luis Creek Mouth- Avila Beach, CA
- Linda Mar Beach - Pacifica, CA
- South Sound Thea Foss Floating Dock - Tacoma, WA
- Playa Crashboat - Aguadilla, PR
- Park View Kayak Launch - Miami Beach, FL
- Ballard Park - Melbourne, FL
- Windmill Beach - Sag Harbor, NY