Bacteria risk, seasonal safety, and DOH advisories
📍 North Shore, Oʻahu — Near Ehukai / Pipeline
During summer swimming season, Sunset Beach has low bacteria risk. The open ocean exposure, powerful wave action, and minimal urban runoff all contribute to excellent water quality. There is very little development directly behind the beach to contribute contamination.
The small Kaunala Stream drains onto the north end of the beach and can briefly elevate bacteria after heavy rain, but the stream volume is small and the ocean flushes it quickly.
Based on: Open ocean exposure, minimal urban runoff, DOH North Shore monitoring history
North Pacific swells subside and the beach becomes calm and swimmable. Water quality is typically excellent. Snorkeling is possible near the rocky points on the south end. Crowds are light compared to winter spectator season.
North Pacific swells arrive and can reach 20-40+ feet. The beach is transformed into a world-famous big wave surf venue. Even on “small” winter days, shore breaks and rip currents make swimming dangerous. Spectating from the beach is popular but stay back from the waterline.
Even in summer, wait 72 hours after heavy North Shore rain before swimming. Kaunala Stream and road runoff can briefly elevate bacteria near the north end of the beach. The south end recovers faster.
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⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent project not affiliated with the Hawaii DOH. Ratings are estimates — not real-time measurements.
Verify with the Hawaii DOH Clean Water Branch before swimming.
When in doubt, don't go out. 🤙