Is it safe to swim at 1 Hotel Hanalei Bay?

1 Hotel Hanalei Bay overlooks Hanalei Bay, which has a High bacteria risk rating (4 out of 5). The Hanalei River discharges directly into the bay, carrying agricultural and residential runoff —Â especially after rain. On dry days the water can test fine, but after storms the bay can be contaminated for days. Kauai's north shore is one of the wettest places on Earth.

Why is Hanalei Bay water quality worse than Poipu?

Hanalei Bay receives direct river discharge from the Hanalei River on one of the wettest coastlines on Earth. Poipu Beach on the south shore is drier, has no major river inputs, and has better ocean flushing. Poipu's bacteria risk is 2 out of 5 compared to Hanalei's 4 out of 5.

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Kauaʻi · North Shore

1 Hotel Hanalei Bay

Water quality at Hanalei Bay

Checking live advisories…

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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, wait at least 72 hours and until the water clears before swimming.

Learn more about brown water advisories →

Historical Bacteria Risk

⚠ 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.

High Risk 4 / 5

The 1 Hotel Hanalei Bay (formerly St. Regis Princeville) overlooks one of the most beautiful bays in Hawaii. Unfortunately, Hanalei Bay also has a High bacteria risk rating (4 out of 5).

The problem is the Hanalei River, which empties directly into the bay. Kauai's north shore is one of the wettest places on Earth. All that rain washes agricultural runoff, residential waste, and soil into the river and straight out to the beach. After heavy rain, the bay can turn brown for days.

During the Feb 23 storms, the Hanalei River flooded enough to close the highway at the bridge. That's the kind of event that sends massive amounts of contaminated water into the bay.

On dry, sunny days, Hanalei Bay is gorgeous and the water can test fine. But the risk is real and frequent, especially in winter.

Based on: DOH monitoring, Hanalei River discharge, north shore rainfall, agricultural runoff, Feb 2026 flooding

⚠️ The 72-Hour Rain Rule

The Hawaii Department of Health recommends staying out of the ocean for at least 72 hours after heavy rain, even if the water looks clear. Bacteria and pollutants from runoff can linger in the water longer than the brown color does.

Nearby Beach Guides

🏖 Hanalei Bay

Your beach · Full water quality data

4 / 5

🏖 Poipu Beach

South shore · Much cleaner water

2 / 5

🏖 Kalapaki Beach

East side · Worst on Kauai

5 / 5

Area Comparison

Poipu vs Hanalei Water Quality →

Check all Hawaii beaches & hotels →

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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, 1 Hotel Hanalei Bay, or any government agency or hotel brand. 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.

This site is a work in progress and we want to make it better. If you notice something that isn’t working right, have a suggestion, or want to share local knowledge about a beach, please reach out.

When in doubt, don’t go out. 🤙