advisory-freeBrown Water AdvisoryBeach Advisory (bacteria)
Historical Pattern · 3-year monthly
Historically most advisory-free in January (100% advisory-free) and most advisoried in April (67% advisory-free). Current 30-day window is tracking about average for August.
Source: Hawaii DOH Clean Water Branch · Updated 2026-08-13
⚠
If It Looks Brown, Don't Swim
Never enter the ocean when the water appears brown or murky. After heavy Kauaʻi rain, streams near Poʻipū can spike bacteria. Wait 72 hours.
⚠ Historical rating — based on long-term testing data, not current conditions.
Moderate Risk3 / 5
Brennecke Beach is adjacent to Poʻipū Beach Park, which the DOH monitors as a Tier 1 beach. The Poʻipū area has moderate bacteria risk due to nearby resort development and the Waikomo Stream that drains into this part of the coast. Historical DOH data shows periodic bacteria exceedances in the Poʻipū area after rain events.
Under dry conditions the water quality is generally acceptable. The main risk window is during and immediately after significant rainfall, when stream discharge can introduce bacteria. The open south-facing coast helps with ocean flushing between events.
Based on: DOH Tier 1 monitoring at adjacent Poʻipū Beach Park, Waikomo Stream runoff risk, South Shore exposure
⚠️ The 72-Hour Rain Rule
The Department of Health recommends at least 72 hours after heavy rain before ocean entry. Waikomo Stream near Poʻipū is a known bacteria source after storms. Always check the water before entering.
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