Water quality status and bacteria risk rating — Can you swim today?
📍 South shore Molokaʻi, 3 miles east of Kaunakakai
One Aliʻi is a calm, shallow south-shore beach park that local families use for swimming and picnicking. The reef keeps the water protected, but circulation is slow and there are cesspools in the nearby community, so bacteria can linger after rain. DOH does NOT test Molokaʻi beaches — there is no live advisory system for this location.
Based on geographic analysis, One Aliʻi Beach Park likely has low-moderate bacteria levels most of the time. The sheltered south shore inside the reef stays calm and clear in good conditions, and most days the water looks swimmable to local families who use the park.
Two factors pull the rating up from a 1 out of 5: (1) Limited circulation behind the reef means bacteria from runoff clears more slowly than on open-ocean shores, and (2) the nearby Kaunakakai residential area relies on on-site wastewater systems (cesspools), which can seep into nearshore groundwater. Historical bacteria reports on rural Hawaii south shores show these two factors frequently elevate counts after rain.
However: This is an estimate only. The Hawaii Department of Health does NOT monitor any Molokaʻi beaches. There is no testing data to confirm water quality. “No DOH Alerts” means no data exists — not that it was tested clean. Always use visual inspection before entering the water.
Based on: Geographic analysis only (no DOH data). Sheltered bay, limited circulation, residential cesspool density nearby.
The Department of Health recommends staying out of the ocean for at least 72 hours after heavy rain. For sheltered south-shore beaches like One Aliʻi, where circulation is limited, you may want to wait longer. Since DOH does not monitor any Molokaʻi beaches, there is no testing data to confirm when the water actually clears. Use extra caution and rely on visual inspection. See our Swimming After Rain in Hawaii guide for more details.
*Estimated — DOH does not monitor Molokaʻi beaches
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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 clean. DOH only monitors a fraction of Hawaii’s beaches, and some areas have no regular testing at all.
Molokaʻi beaches are NOT monitored by DOH. The ratings on this page are geographic estimates only. Always verify conditions visually before entering the water. Check with the Hawaii Department of Health Clean Water Branch for the latest information.
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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