The goal of BWTF is to fill in monitoring gaps and quickly communicate with the public where it is safe to swim and where bacteria levels are elevated. Water quality results are compared to the standards used by the Hawaiʻi Department of Health (HDOH) to make beach closure decisions. Known as the Beach Action Value (BAV), this threshold is set at 130 colony forming units of Enterococcus per 100mL sample (130 CFU/100mL).
In 2022, eight sites (Kūʻau Cove/Mamaʻs Beach, Wawau Point/Baby Beach, Hoʻokipa Beach Park West, Pāʻia Bay, Sugar Cove, Kahului Harbor, Wailuku Stream, and Māliko Bay) had at least one sample that exceeded state health standards. This was higher than in 2021 where five sites had at least one sample exceed.
Over the last two years, samples from Wailuku Stream, Māliko Bay, and Kahului Harbor have measured high bacteria levels that exceed the state health standard more frequently than the other sites tested. Kahului Harbor is located in an urban area and while the other two sites are located at the mouth of streams or rivers. Water quality conditions at these sites can likely be attributed to land- based runoff from upland areas that is carried by freshwater streams to the ocean.
Topping the list, for the second year in a row, is Wailuku Stream with 27% of samples exceeding health standards in 2022. This site also had the highest single bacteria reading last year of 4,366 Enterococcus mpn/100mL (the state standard is 130 mpn/100mL). The contributing watershed and nearby coastline has a particularly high concentration of cesspools.The chronic pollution documented by the BWTF at this site indicates the potential impact of sewage pollution.
2022 was the first year that water quality samples were collected in Hāna. Though sample size was limited, Haneoʻo Fish Pond had consistently high bacteria levels. It is likely that the fish pond has freshwater inputs & land-based sources of pollution contributing to high bacteria levels. Additional data from Hāna will allow us to develop a better understanding of water quality trends at these sites.