Health advisory issued for Kahaluu Beach Park after bacteria spike

Kahaluu Beach Park, one of Kona’s signature family beaches and snorkel stops, was under a health advisory after routine testing found elevated enterococci bacteria in the water. The warning put swimmers, snorkelers and nearby businesses on notice at a site that draws more than 400,000 visitors a year.

The Hawaii State Department of Health’s Clean Water Branch said the beach was being retested and urged people to avoid water contact until further notice. Enterococci are used as an indicator of fecal contamination. They do not by themselves identify the exact germ in the water, but they can signal that sewage, runoff or other land-based pollution may have entered the bay.

Health officials set a Beach Action Value of 130 enterococci per 100 milliliters of water. When routine monitoring goes above that level, the department collects follow-up confirmatory samples quickly. In this case, the department said the reading was considered potentially unrepresentative because Kahaluu Beach Park has historically met the acceptable threshold and no known source of fecal contamination had been identified.

The advisory matters far beyond the shoreline. Kahaluu Bay is one of the most popular snorkeling sites in the state, and any warning can ripple through Kailua-Kona’s visitor economy, from tour operators and beach rentals to food trucks and nearby shops that depend on steady beach traffic. Families who use the park for a quick swim after school or on weekends were among the people most likely to change plans immediately.

This was not the first time Kahaluu has flashed a warning. On Aug. 26, 2025, the department detected 164 enterococci per 100 milliliters at Kahaluu Beach Park and canceled that notification three days later, on Aug. 29, 2025. On Jan. 16, 2026, a more severe sample of 2,005 enterococci per 100 milliliters was reported before follow-up testing brought levels back below the state threshold and the advisory was lifted.

Researchers and environmental advocates have long pointed to Kahaluu as a bacteria hot spot, with concerns tied to cesspools, stream-fed runoff and wastewater from nearby homes. A University of Hawaii thesis cited department criteria identifying Kahaluu as a Priority 1 Area with 740 cesspools.

The department warns that children, older adults, people with weakened immune systems and anyone with open wounds are most at risk after contact with polluted water. The all-clear will come only after confirmatory samples fall back below the state benchmark and the water again meets safe recreational standards.