Water quality status & sea turtle habitat guide
📍 South Kohala, Big Island — Remote 4WD access, no facilities
Kiholo Bay has excellent water quality — one of the Big Island's most pristine coastal environments. The bay is fed by abundant freshwater springs bubbling up from the volcanic rock, creating the distinctive brackish lagoon and unusually clear water. The remote location and minimal human impact mean bacteria contamination is extremely rare.
The spring-fed water keeps the inner lagoon (Queen's Bath / Luahinewai) exceptionally clear and warm. This ancient Hawaiian fishpond was historically used to raise fish and is now a protected area. Hawaiian green sea turtles (hōnū) are frequently seen resting on the lava shores and swimming in the bay.
Based on: Freshwater spring input, remote location, minimal human impact, no monitored pollution sources
After significant rainfall on the Kohala mountains above, freshwater runoff can temporarily cloud the bay water. Wait at least 24–48 hours after heavy rain before swimming. If the lagoon water looks murky or discolored, skip swimming that visit.
Rough dirt road off Hwy 19 near mile marker 82. High-clearance 4WD recommended. Or hike ~1.5 miles along the lava coast.
Stay 10+ feet from turtles. Do not touch, chase, or feed them. Approaching within 10 feet is illegal under the Marine Turtle Protection Act.
No restrooms, no shade, no drinking water, no cell service. Bring everything you need including sun protection, food, and water.
The brackish lagoon is calm and safe for most swimmers. The open ocean bay can have stronger currents — experienced swimmers only.
Free Big Island water quality alerts — brown water advisories and bacteria warnings before you head out.
No spam. Just safety alerts for your trip.
⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent passion project — not affiliated with the Hawaii Department of Health. Ratings are estimates based on available data and are not real-time measurements. Kiholo Bay is not regularly monitored by the DOH.
Always verify conditions with the Hawaii DOH Clean Water Branch before entering the water.
When in doubt, don't go out. 🤙