Health Advisory Issued After High Bacteria Detected at Onekahakaha Beach

A health advisory was issued for Onekahakaha Beach Park in Hilo after routine testing found elevated bacteria levels in the water, prompting state officials to urge caution for beachgoers. The Hawaiʻi State Department of Health announced the advisory on Jan. 21, 2026, after a routine water-quality test measured 192 enterococci per 100 milliliters, a result that exceeds the state’s beach action threshold.

Enterococci are monitored as indicators of possible fecal contamination. The Department of Health said Onekahakaha historically meets acceptable water-quality standards and that no specific fecal-contamination source has been identified for this incident. Additional samples were collected for follow-up testing, and the public will be updated when retest results are available.

The advisory advises caution particularly for people with open wounds and those with compromised immune systems until testing confirms the water is safe. Local residents who use Onekahakaha for swimming, family outings, or exercise should consider avoiding contact with the ocean there until the Department of Health clears the site. Keiki, kupuna, and anyone with a recent surgery or chronic illness are at greater risk if exposed to contaminated water.

Routine surveillance sampling is a standard public-health practice designed to catch transient contamination events before they pose widespread risk. When tests show elevated indicator bacteria like enterococci, officials typically collect follow-up samples to determine whether levels remain high or return to normal. A single elevated sample can reflect a brief contamination event from runoff, wildlife, sewage system issues, or other environmental factors, but the Department of Health has not identified a source in this case.

For Big Island County residents, the immediate impact is precautionary. Recreation plans that involve swimming at Onekahakaha may need to be adjusted until authorities post a clear result. Fishermen and others who use the shoreline for non-swimming activities should weigh the risk if they are in direct contact with seawater, especially if they have cuts or compromised health.

The Department of Health will post updates when follow-up tests are complete. Until then, residents are advised to heed the advisory, avoid entering the water at Onekahakaha if possible, and seek medical advice if they develop symptoms after exposure. The retest results will determine whether the beach returns to routine status or if further investigation into potential contamination sources is required, shaping next steps for public safety and local use of the shoreline.