HANALEI — Carl Berg, chairman of the Surfrider Foundation of Kaua‘i, said recently that while Kaua‘i’s beaches and surf spots remained, on the whole, pretty clean, Kaua‘i’s rivers remain contaminated with bacteria.
“If you are going to ask the Department of Health, ‘Are our (ocean) waters polluted?’” Berg said, “On the basis of their sampling … there (are) only two places (the Hanalei River at Weke Road and Hanama‘ulu Beach Park) really that can be considered polluted. And those are really at the river mouths, they’re not the beach areas.”
Berg presented the latest information on water quality in front of a small crowd at Hale Halawai Community Center in Hanalei recently. Most of Kaua‘i’s beaches and surf breaks met DOH water quality standards during 2012, the island’s rivers and streams, affected by run-off and ground water contamination, are polluted, he said.
Water quality data is collected weekly by the Hawai‘i DOH at ocean beaches around the island, and monthly samples are collected by Surfrider’s Blue Water Task Force at surf breaks and streams, according to Berg.
Water samples are collected and tested for Enterococcus, an indicator of fecal contamination.
“(The DOH is) really concerned about how people get sick from being in that water, and the main source of getting that sickness is the viruses and the bacteria that are coming from sewage,” Berg said. “But there are other things we’re concerned about, with respect to the coral reefs and respect to the fishes and everything else here.”
Those concerns include nutrients, sediment, pesticides, detergents, personal care products and ocean acidification, which Berg noted has been identified as one of the major threats to coral reefs worldwide.
In a 100 ml sample, Berg said there should be less than 104 counted bacteria. If the count exceeds 104, the water is considered polluted. The geometric average of five collected samples should not exceed more than 35 bacteria per 100 ml.
“The idea here is that you’re going to have occasions, like today when it’s raining a lot, where you may have a spike (in bacteria), but that’s not really telling you the overall condition of that beach, or that water,” Berg said. “That’s telling you what happened one day.”
During 2012, DOH staff and Surfrider field assistants collected water samples from a total of 30 different sites, according to the Blue Water Task Force’s 2012 Annual Report. Eight of those sites were sampled on a weekly basis over the course of 2012, with another 11 sites sampled weekly over a six month period.
Of those 19 locations, six never exceeded the single sample pollution standard, and 13 were polluted less than 10 percent of the time.
The two worst DOH test sites were the Hanalei River mouth at Weke Road, which was polluted 42.6 percent of the time, and Hanama‘ulu County Beach Park, polluted 60.9 percent of the time.
“(Hanama‘ulu) has a really high count, that’s like four times the allowable limit,” Berg said. “This is actually good. A couple of years ago, it was something like 97 percent of the time it was polluted and it made the top ten list nationwide as being polluted.”
Those two locations were the only DOH sites with a geometric average greater than 35 bacteria colonies per 100 ml, suggesting that pollution is mainly coming from river water, according to Berg.
The DOH is currently finishing a DNA study of the bacteria at 14 beach sites around Kaua‘i to determine if they are from human or animal sources.
Using a team of volunteers, Surfrider collects its own water samples from streams and offshore surf breaks on a monthly basis, testing them for bacteria using the same tests as DOH.
While most surf breaks — with the exceptions of Wainiha and Pakalas — met DOH standards, Berg said Kaua‘i’s “streams and rivers are definitely not clean.”
In 2012, four locations — Waikomo Stream at Koloa Landing, Nawiliwili Stream in Kalapaki Bay, Hanama‘ulu Stream and Niumalu Beach Park near Pu‘ali Stream — were polluted 100 percent of the time.
Niumalu County Beach Park had the highest geometric average at 1,211 bacteria per 100 ml — nearly 35 times the allowable limit — followed closely by Koloa Landing at 1,182, Nawiliwili Stream at 662 and Hanama‘ulu Stream at 582.
With the assistance of DOH, Surfrider is also doing extensive weekly sampling at the mouths of all streams entering Hanalei Bay to determine the quality of the water going into the bay.
“All of the streams are polluted,” Berg said during the presentation last week.
Waikoko Estuary had the highest geometric average at 529 — more than 15 times the allowable limit — and was polluted 100 percent of the time during 2012. Waioli Estuary tested above the DOH standard for pollutants 98 percent of the time, followed by Waipa Estuary at 90 percent, Hanalei River at Weke Road at 54 percent, Waileia Estuary (Hanalei) at 37 percent, Waileia Estuary (Princeville) at 35 percent and the U.S. Geological Survey’s Hanalei River test site at 19 percent.
Berg said future water quality presentations focusing on local areas are being planned for Lihu‘e and Hanapepe.
The most recent values for Surfrider Foundation samples taken on the second Saturday of each month can be found at www.surfriderkauai.ning.com.