Water quality status and swimming conditions
📍 Waimanalo, Oʻahu — Quiet east side alternative
Kaiona Beach Park sits at the southern end of the Waimanalo coastline on Oʻahu’s windward east side. This is a quiet, local beach that sees far fewer tourists than Kailua or Waikiki. Water quality historically tests within baseline but can be impacted by a small stream near the park, especially after heavy rain on the Koʻolau Mountains above.
The beach has soft white sand — Waimanalo is known for some of the finest sand on Oʻahu. There are no lifeguards, so swimming requires caution. The area is popular with local families for picnics, fishing, and swimming. Trade wind swells can make conditions choppy in the afternoon.
Based on: Small stream nearby, windward exposure, limited urban runoff, no lifeguards
After heavy rain, stay out of the water for at least 72 hours. The Koʻolau Mountains behind Waimanalo receive heavy rainfall — streams drain directly onto the beaches here. Watch for brown or murky water near the stream outlet.
Top-rated experiences near this beach. Check water quality above, then plan your trip.
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⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent passion project — not affiliated with the Hawaii Department of Health. Water quality ratings are estimates based on historical data and are not real-time measurements.
Always verify with the Hawaii Department of Health Clean Water Branch before swimming.
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. 🤙