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BIG ISLAND · KAILUA-KONA

Royal Kona Resort

Ocean water quality and nearby beach guide for Kailua-Kona

📍 75-5852 Aliʻi Dr, Kailua-Kona, Big Island

Checking live advisories…
If It Looks Brown, Don't Swim
After heavy rain, even Kona's dry coast can see runoff. Wait 72 hours after heavy rain before ocean entry.
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Ocean Water Quality — Kailua-Kona Area
⚠ Historical rating — based on long-term data, not current conditions.
Very Low Risk 1 / 5

The ocean water along Kailua-Kona's waterfront where the Royal Kona sits has very good water quality. The Kona Coast has an extremely dry climate with minimal stormwater runoff, and the deep, clear open-ocean water flushes the coastline continuously. Bacteria counts in this area are among the lowest on the Big Island.

Note: The Royal Kona does not have a sandy beach. The property has a salt-water pool and lava rock ocean access. For sandy beach swimming, the nearest options are Magic Sands Beach (Laʻaloa) and Kahaluʻu Beach Park, both a short drive south.

Based on: DOH Kona monitoring, dry leeward climate, deep open-ocean exposure

⚠️ The 72-Hour Rain Rule

The Kona side of the Big Island is Hawaii's driest area, but heavy rain does occasionally occur. After any significant rainfall, wait at least 72 hours before ocean entry.

Best Beaches Near Royal Kona Resort
🏖 Kahaluʻu Beach Park — 3 miles south

Best snorkeling near Kona. Protected cove with sea turtles, reef fish, and calm conditions. Very low bacteria risk.

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🏖 Magic Sands Beach (Laʻaloa) — 2 miles south

Small white-sand beach that "disappears" in winter swell. Best in summer for calm conditions. Popular local spot.

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🏖 Kua Bay (Maniniowali) — 20 miles north

Stunning white-sand beach in a lava bay. Crystal clear water. Worth the drive for a perfect beach day.

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Get Beach Safety Alerts

Free Big Island water quality alerts — brown water advisories and bacteria warnings.

Understanding Water Quality in Hawaii

Hawaii’s Department of Health monitors approximately 57 beaches statewide through regular bacteria testing. However, with over 300 swimmable beaches across the islands, many popular spots have no regular testing program. Water quality varies significantly based on rainfall, stream proximity, coastal development, and ocean circulation patterns.

After heavy rain, streams and storm drains carry bacteria, sewage, pesticides, and sediment into coastal waters. The DOH recommends staying out of the ocean for at least 48 to 72 hours after heavy rain, even if the water appears clear. Brown or murky water is a visible sign of contamination, but bacteria can be present in clear water near stream mouths.

This site aggregates data from six sources — DOH advisories, USGS stream monitoring (25 stations), NOAA tide and temperature data, NDBC wave buoys, NWS weather alerts, and City & County of Honolulu water testing — to provide a more complete picture than any single source.

72-Hour Rain Rule

The 72-hour rule is the standard guideline from the Hawaii Department of Health: avoid swimming for at least 72 hours after heavy rain stops, especially near stream mouths, canal outlets, and areas with brown or discolored water. This applies to all beaches across all islands.

Bacteria from urban runoff, agricultural land, and aging cesspool systems enters the ocean through streams and storm drains. Hawaii has approximately 88,000 cesspools — more than any other state — many of which leak untreated sewage into groundwater that eventually reaches the coast. Beaches near known cesspool contamination areas carry higher risk, particularly after rainfall.

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⚠️ Important Disclaimer

Safe to Swim Hawaii is an independent passion project — not affiliated with the Hawaii Department of Health. Ratings 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. 🤙

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