Nearly two-thirds of Kaua‘i’s tested waters polluted

LIHU‘E — Washing off isn’t supposed to make you dirtier. But depending on where you’re swimming, it just might.

Every month, Surfrider Kaua‘i’s Blue Water Task Force analyzes samples of streams, rivers and surf spots across the island to check for the enterococcus bacterium, a federally recognized indicator of fecal presence in water.

July’s batch of tests, taken July 8, showed an unfortunate turnaround from June’s test, in which only six of 17 sites tested below state water quality standards — the year’s cleanest results.

This month, 10 of the 16 sites tested (Hanama‘ulu Beach, Kalihiwai Surf, Hanalei Bowl, Kalapaki Bay Surf, Hanalei River, Pakala Surf, Middles Surf, Nawiliwili Stream, Hanama‘ulu Stream and Moloa‘a Stream) produced results below Hawai‘i’s single-day sample standard of 130 enterococci per 100 milliliters of water.

However, Surfrider Kaua‘i senior scientist Carl Berg suggested the large differences in results between months could be attributed to variations in rainfall on testing days —which can wash pollutants into streams and beaches — rather than a sudden island-wide shift.

“Sometimes we’re out in the middle of a rainstorm and it’s pouring rain, and other times we’re out in the middle of a two-month drought,” Berg said “This is why, from month to month, we may have highly different values at the same stream.”

Berg notes while testing this way can create large variations between months, testing on set days — in Surfrider Kaua‘i’s case, every second Saturday — creates more accurate, longer term indicators of water quality.

“The important part is when you look at it on a broader picture, for one year or five years or 10 years, which of these areas are clean and which of them are not clean,” he said. “The geomean values that we’re giving you tell you what the average condition of that location is.”

The task force’s year-to-date geomean — essentially the site’s average bacterial concentration in 2023 — shows seven tested sites below the state’s water quality standard of 35 enterococci per 100 milliliters of water (Wainiha Stream, Hanama‘ulu Beach, Hanalei River, Nawiliwili Stream, Hanama‘ulu Stream, Moloa‘a Stream and Koloa Landing).

Contamination of Kaua‘i’s waters stems largely from surface runoff, which can pull animal and chemical waste along, and groundwater, which can leech human and chemical waste from the island’s 14,000 cesspools. These pollutants can become concentrated in rivers and streams, which then push them out into beaches and surf sites.

Swimming in water contaminated by excrement isn’t just gross — it can cause real health problems for the island’s swimmers and surfers.

“What water people experience most in Hawai‘i is gastrointestinal problems, eye infections, ear infections, sore throats,” Berg said. “But we always can have a new pathogen introduced to our waters.”

Berg notes that more serious illnesses can occasionally appear in beaches and streams, sometimes as a result of animal excrement being picked up from surface runoff, and sometimes as a result of humans unknowingly bringing new or uncommon pathogens to the island.

To avoid contracting illnesses from the waters, Berg recommends checking Surfrider’s water quality reports to avoid high streams and beaches with bacterial concentration geomeans, as well as staying out of visibly brown waters.

“Our advice is to always go to good, clean places,” he said.

Additionally, Berg advises beachgoers to wash off as soon as they get out of a beach or stream.

“Rinse off your face and your eyes,” he said. “Rinse off to wash these pathogens off your body as soon as you get out of the water. That’s the very best thing to do.”

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Jackson Healy, reporter, can be reached at 808-647-4966 or jhealy@thegardenisland.com.