What to expect for water quality, rainfall, and ocean conditions
Heavy winter rain increases Waimea River discharge. Combined with dangerous surf, Waimea Bay is not recommended for swimming during the winter wet season.
March brings the last of the major winter swells to Waimea Bay. The bay alternates between large surf days and increasingly calm periods. Rainfall begins decreasing. Late-season storms can still bring big waves.
Winter brings massive north swells to Waimea Bay, some of the largest rideable waves on Earth. The bay is closed to swimming during big surf events. Powerful currents and shore break make the water extremely dangerous.
Very high. March is spring break season with families and college students. Popular beaches fill early in the morning.
The Hawaii Department of Health recommends staying out of the ocean for at least 72 hours after heavy rain. In march, this is especially important as wet-season storms can produce heavy rainfall and significant runoff.
When conditions are clear, Waimea Bay has excellent ocean activities. Check the water quality above, then book with confidence.
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Safe to Swim Hawaii provides water quality information based on publicly available DOH data and seasonal patterns. This is not medical or safety advice. Always check current conditions, obey posted signs, and use your own judgment before entering the ocean. Privacy Policy
⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent passion project — not affiliated with the Hawaii Department of Health or any government agency. Water quality ratings are estimates based on publicly available testing data and geographic analysis. They are not real-time measurements and may not reflect current conditions.
Always verify current water quality conditions with the Hawaii DOH Clean Water Branch before entering the water.
When in doubt, don't go out. 🤙