Every island, every coastline — ranked by bacteria testing data and real water quality conditions
Hawaiʻi has hundreds of beaches, but water quality varies dramatically depending on location, nearby development, and ocean conditions. This guide ranks the best beaches across all four major islands based on DOH bacteria testing data, geographic exposure, and proximity to pollution sources.
Ratings reflect long-term historical patterns, not real-time conditions. Always check for current DOH advisories and avoid swimming when water looks brown or murky.
Crystal-clear water with strong tidal flushing through the Mokulua Islands. Minimal development runoff. One of the cleanest beaches in all of Hawaiʻi.
Long stretch of white sand with historically baseline water quality. Kawainui Marsh can contribute runoff after heavy rain, but normal conditions are excellent. Full lifeguard service and facilities.
Three miles of pristine sand with excellent open-ocean flushing. Less crowded than Kailua and Lanikai with consistently clean water.
Man-made lagoons with calm, protected water. Limited flushing can trap bacteria in enclosed areas. Best on calm, dry days.
Iconic snorkeling destination with good water quality. Visitor caps help protect the bay. Sheltered cove with moderate flushing.
See all: Safest beaches on Oʻahu · Oʻahu island guide
Sheltered crescent bay with consistently excellent water quality. Minimal runoff sources and good natural flushing. World-class snorkeling.
South Maui’s dry climate means very little runoff. Consistently clean water with open-ocean exposure. Major resort beach with full facilities.
Calm crescent bay popular with families. Good water quality under normal conditions. Sea turtle sightings are common.
Stunning wide-sand beach with excellent water quality due to open-ocean exposure and minimal development. Watch for powerful shorebreak.
See all: Safest beaches on Maui · Maui island guide
Wide white-sand beach on the dry Kohala Coast. Minimal rainfall means very little runoff. Consistently among the cleanest beaches in all of Hawaiʻi.
Pristine white-sand beach surrounded by lava rock. Extremely remote from development with excellent water quality. Strong shore break on bigger days.
Calm, protected beach great for families. Good water quality with lifeguard service. Adjacent to Puʻukoholā Heiau historic site.
See all: Safest beaches on the Big Island · Big Island guide
Kauaʻi’s south shore is the driest area on the island, resulting in consistently clean water. Protected swimming area with lifeguards. Great for families.
Protected by the longest fringing reef in Hawaiʻi. Calm, shallow water with generally good quality. Popular with snorkelers and families.
Rock-walled swimming pools provide safe, calm water. Near the Wailua River which can contribute runoff after rain. Excellent playground and facilities.
See all: Safest beaches on Kauaʻi · Kauaʻi island guide
Water quality at Hawaiʻi beaches depends on several key factors:
Open-ocean beaches with strong currents flush bacteria quickly. Enclosed bays and lagoons can trap contaminants.
Beaches on dry leeward coasts (South Maui, Kohala Coast, south Kauaʻi) tend to have cleaner water than those in wet windward areas.
Cesspools, sewage infrastructure, and urban stormwater drains can introduce bacteria. Hawaiʻi has roughly 88,000 cesspools statewide.
Beaches near stream outlets receive more land-based runoff, especially after rain. The 72-hour rain rule is critical near streams.
Top-rated experiences near this beach. Check water quality above, then plan your trip.
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100+ beaches and 25+ hotels across all 6 islands
DOH only tests roughly 47 stations across the four main islands — zero on Molokaʻi or Lānaʻi. Surfrider Foundation’s volunteer Blue Water Task Force adds 100+ community-tested sites on Oʻahu, Maui, and Kauaʻi, but it does not cover Molokaʻi or Lānaʻi. Plus our year-over-year and stream-mouth analysis pages put the daily numbers in context.
⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent passion project — it is not affiliated with the Hawaii Department of Health or any government agency. Water quality ratings on this site are estimates based on publicly available testing data and geographic analysis. They are not real-time measurements and may not reflect current conditions. “No DOH Alerts” means no advisory is currently posted — it does not mean the water was tested and found safe. DOH only monitors a fraction of Hawaii’s beaches, and some areas have no regular testing at all.
Always verify current water quality conditions with the Hawaii Department of Health Clean Water Branch before entering the water. This site is for informational purposes only and should not be the sole basis for any swimming decisions.
This site does not recommend or advise anyone to swim at any beach. We share government data and geographic analysis so you can make your own informed decisions. By using this site you accept full responsibility for your own safety. See our Terms of Use for full details.
When in doubt, don't go out. 🤙