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OAHU · WEST SIDE

Ko Olina Lagoons

Water quality status and bacteria risk rating

Also known as: Disney Beach, Aulani Beach

📍 On Oʻahu's west coast, about 30 minutes from Waikiki, near Aulani Disney and the Four Seasons

Checking live advisories…
30-Day Water Quality History
9/30 days under DOH advisory · 21 days clean
Apr 15 · Brown Water AdvisoryApr 16 · Brown Water AdvisoryApr 17 · Brown Water AdvisoryApr 18 · Brown Water AdvisoryApr 19 · Brown Water AdvisoryApr 20 · Brown Water AdvisoryApr 21 · Brown Water AdvisoryApr 22 · Brown Water AdvisoryApr 23 · No active advisoryApr 24 · No active advisoryApr 25 · No active advisoryApr 26 · No active advisoryApr 27 · No active advisoryApr 28 · No active advisoryApr 29 · No active advisoryApr 30 · No active advisoryMay 1 · No active advisoryMay 2 · No active advisoryMay 3 · No active advisoryMay 4 · No active advisoryMay 5 · No active advisoryMay 6 · No active advisoryMay 7 · No active advisoryMay 8 · No active advisoryMay 9 · No active advisoryMay 10 · No active advisoryMay 11 · No active advisoryMay 12 · No active advisoryMay 13 · No active advisoryMay 14 · No active advisory
Apr 15 today (May 15)
1 Brown Water Advisory
Trend: ▼ improving
clean Brown Water Advisory Beach Advisory (bacteria)
Historical Pattern · 3-year monthly
January — 86% clean historicallyFebruary — 85% clean historicallyMarch — 87% clean historicallyApril — 82% clean historicallyMay — 92% clean historicallyJune — 100% clean historicallyJuly — 92% clean historicallyAugust — 100% clean historicallySeptember — 100% clean historicallyOctober — 100% clean historicallyNovember — 97% clean historicallyDecember — 84% clean historically JFMAMJJASOND
Historically cleanest in June (100% clean) and most advisoried in April (82% clean). Current 30-day window is tracking above typical May advisory frequency.
Source: Hawaii DOH Clean Water Branch · Updated 2026-05-15
If It Looks Brown, Don't Swim
Never enter the ocean when the water appears brown or murky, even if no advisory is posted. Hawaii is often slow to test beaches and update advisories — not every beach is monitored. After heavy rain, wait at least 72 hours and until the water clears before swimming.
Learn more about brown water advisories →
Historical Bacteria Risk
⚠ Historical rating — this is based on long-term testing data, not current conditions. The state of Hawaii is often slow to test beaches and update advisories. Always check the water yourself and avoid brown or murky water.
Moderate Risk 2 / 5

Ko Olina's four man-made lagoons have generally acceptable water quality under normal conditions. The lagoons self-clean via ocean currents through breakwater openings, but their enclosed shape means water turns over more slowly than at open beaches.

Landfill proximity: The Waimanalo Gulch Landfill (Oahu's only municipal landfill) sits directly behind Ko Olina. In 2010–2011, heavy storms caused contaminated stormwater and medical waste to reach the ocean, closing the lagoons. An EPA consent decree was completed in 2023 with infrastructure upgrades. No major stream runoff feeds into the lagoons under normal conditions.

Based on: DOH Tier 1 monitoring, EPA consent decree history, man-made lagoon circulation assessment

⚠️ The 72-Hour Rain Rule

The 72-hour rule applies to Ko Olina's lagoons. Because the lagoons are enclosed with limited water exchange, bacteria and pollutants from storm runoff can take longer to flush out than at open beaches. Be especially cautious after heavy rainfall. The proximity of the Waimanalo Gulch Landfill means severe storms could potentially carry additional contaminants.

Ko Olina Lagoons Area Hotels — Historical Beach Water Quality
🏨 Aulani Disney Resort
Lagoon 2, directly on the water
Moderate
🏨 Four Seasons Ko Olina
Lagoon 1, west end of resort
Moderate
Ko Olina Lagoons Water Quality by Month
January February March April May June July August September October November December
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⚠️ 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.

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When in doubt, don't go out. 🤙

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