Water quality status and bacteria risk rating
📍 Haʻena, North Shore Kauaʻi. Near the end of the road before Nā Pali coast.
Tunnels Beach (Makua Beach) has excellent water quality. The outer reef creates strong water circulation with excellent ocean flushing. No significant stream discharge feeds into the beach area.
This is one of the cleanest snorkeling spots on Kauaʻi from a bacteria standpoint. The reef formations that create the famous "tunnels" also promote excellent water flow. Open ocean exposure on the North Shore ensures strong natural flushing. The main safety concern is strong currents outside the reef, especially during winter months — not bacteria. No lifeguards are present.
Based on: Open ocean exposure, outer reef circulation, no stream discharge
Even at low-risk beaches like Tunnels Beach, the Department of Health recommends staying out of the ocean for at least 72 hours after heavy rain. Tunnels Beach is well-protected from runoff with no significant stream discharge, but Kauaʻi's North Shore receives heavy rainfall and island-wide storms can temporarily affect any coastal area. The primary safety concern here is currents and surf conditions, not bacteria.
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 — 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. 🤙