Oʻahu's two biggest family resorts compared on water quality
Beach: Duke Kahanamoku Beach / Hilton Lagoon
The Hilton has its own lagoon plus access to Duke Kahanamoku Beach. Located in Waikiki, it is influenced by the Ala Wai Canal but sits at the western end, which is typically cleaner than central Waikiki.
Beach: Ko Olina Lagoons
Aulani's Ko Olina lagoons are man-made, calm, and located far from urban Honolulu's runoff. No Ala Wai Canal influence. The lagoons have moderate risk mainly from occasional stormwater, not chronic urban pollution.
Aulani wins on water quality because Ko Olina is far removed from Waikiki's Ala Wai Canal, the primary source of bacteria contamination on O'ahu's south shore. Ko Olina's lagoons are man-made with ocean flushing, located on the dry leeward coast where rainfall and runoff are minimal. The Hilton's Waikiki location means proximity to urban runoff, sewage infrastructure, and the Ala Wai. While both carry a 2/5 risk rating, Aulani's pollution sources are less chronic than Waikiki's.
Water quality risk ratings are based on publicly available data from the Hawaii Department of Health Clean Water Branch, EPA impaired waters database, USGS stream monitoring data, and geographic analysis of pollution sources (streams, cesspools, storm drains). Ratings are estimates and may change with conditions.
Top-rated experiences near these hotels. Check water quality above, then plan your trip.
Tours listed via Viator and GetYourGuide. Safe to Swim Hawaii may earn a commission if you book, at no extra cost to you.
Free alerts when water quality changes at your beach.
⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent project not affiliated with any hotel, resort, or the Hawaii DOH. Water quality ratings are estimates based on publicly available data — not real-time measurements.
Always verify conditions with the Hawaii DOH Clean Water Branch before swimming.
When in doubt, don't go out. 🤙