advisory-freeBrown Water AdvisoryBeach Advisory (bacteria)
Historical Pattern · 3-year monthly
Historically most advisory-free in March (100% advisory-free) and most advisoried in February (79% advisory-free). Current 30-day window is tracking about average for October.
Source: Hawaii DOH Clean Water Branch · Updated 2026-10-25
Is Hāpuna Beach open? Check park access separately
Before leaving, check Hawaiʻi DLNR State Parks for access notices, park hours and entry or parking requirements.
Match each notice’s date and location: Hāpuna beach day use, the separate Waialea (Beach 69) section, and camping or cabins can have different restrictions. Follow posted signs and staff instructions.
Park access does not establish water quality or safe ocean conditions. Read the current DOH status above and check local surf and lifeguard warnings separately.
⚠
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 stops, avoid affected water for 72 hours as a precaution.
Clear-looking water or elapsed time does not clear an active DOH advisory.
⚠ 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.
Low Risk1 / 5
Hapuna Beach State Recreation Area is on the dry Kohala Coast of Hawaiʻi Island.
Rainfall, runoff and wastewater exposure can vary even along this generally dry coast.
The 1/5 rating above is historical context, not a current bacteria measurement.
It does not establish present water quality or override current DOH advisories, posted signs or local conditions.
Based on: DOH Tier 1 beach monitoring, dry climate, no stream discharge, open ocean exposure
⚠️ After-Rain Precautions
As a precaution, avoid affected coastal water for 72 hours after heavy rain stops,
even if it looks clear. Elapsed time does not clear an active advisory: check current DOH notices and posted signs.
Strong shore break and currents are separate hazards; ask lifeguards about local conditions.
Hapuna Runoff Context
These geographic factors help explain possible runoff exposure. They do not measure present bacteria levels or guarantee clean water:
🌦️
Dry leeward climate
The Kohala Coast is generally dry and leeward. Storms can still produce runoff carrying pollutants to the ocean.
💧
No permanent stream mouth
Hapuna has no permanent stream mouth. Stormwater can still reach coastal water during rain, so this does not rule out runoff contamination.
🌊
Strong ocean circulation
Open-ocean circulation can disperse runoff; it does not guarantee that bacteria or other pollutants are absent.
🏙️
Low population density
The Kohala Coast is less densely developed than urban Waikīkī. Development patterns are exposure context; wastewater pollution can still occur.
How this compares:Waikiki Beach has nearby Ala Wai Canal runoff concerns. Kailua Beach has nearby Kawainui Marsh drainage. Each beach needs its own current advisory and local-condition check.
Seasonal Rain and Surf Patterns
☀️ SUMMER (May–October)
Summer often brings drier weather and smaller north swells. Check current DOH advisories, posted signs and local surf before entering; the season does not establish water quality.
🌊 WINTER (November–April)
Large north and northwest swells can produce powerful shore break and strong currents. Check current DOH advisories as well as surf conditions, and obey lifeguard instructions.
⚠️ KONA STORMS (Rare, Any Season)
Kona low-pressure systems bring unusual south and southwest winds with heavy rain to the normally dry Kohala Coast. These are rare but can temporarily reduce water quality anywhere on the island. After heavy rain stops, follow the precaution above and keep observing any active DOH advisory.
Hapuna vs. Nearby Kohala Coast Beaches
The Kohala Coast stretches along the Big Island's dry leeward shore, home to several resort beaches. Each has its own current advisories, runoff exposure and ocean hazards:
Hapuna Beach
Largest white sand beach on the Big Island. Open ocean, strong shore break in winter.
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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have a suggestion, or want to share local knowledge about a beach, please reach out.
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.