Study: All South Maui beaches exceed sediment standards
Citizen data also show harmful nutrient levels in some waters
KIHEI — Data collected from South Maui’s beaches by Hui O Ka Wai Ola show that “every single site exceeds the state standard” for allowable amounts of sediment and that some offshore waters contain potentially harmful nutrients.
“One of the biggest problems is high nutrient levels followed by turbidity,” said James Strickland, program project manager, at a gathering Wednesday night at the Hawaiian Islands Humpback Whale National Marine Sanctuary.
Nutrient levels can be linked to agricultural runoff or sewage. High amounts can lead to algae blooms, which threaten reefs by blocking sunlight, and bacterial growth harmful to coral, program officials said at the gathering.
Turbidity is a measure of water clarity, such as the amount of sediment carried from the land into the ocean from streams, flooding and other runoff. This can lead to a “brown water event,” which also can block sunlight to reefs, Strickland said.
Hui O Ka Wai Ola’s 45 minute presentation included data from 39 sites — 19 in West Maui and 20 in South Maui. The purpose of the sampling of turbidity and chemicals, such as nitrates, phosphorous and ammonium, is “to reveal the true quality of water regardless of how it looks,” according to Hui O Ka Wai Ola’s website.
“Cove Park is the most impaired,” Strickland said to a jam-packed audience.
Cove Park waters contain levels of nitrates, nitrogen, ammonium, phosphorus and turbidity significantly above state Department of Health limits, according to Hui O Ka Wai Ola data.
For example, the state Health Department’s standard for nitrate content in the ocean is 3.5 micrograms per liter, but Cove Park samples had 350 micrograms. Nitrogen levels were 450 micrograms per liter, while the state standard is 110 micrograms, and ammonium levels, which could be a marker for sewage, were 10 micrograms per liter, exceeding the 2 microgram standard, data showed.
All South Maui beaches sampled exceeded standard turbidity levels and nitrate levels. Cove Park was the only site that surpassed the standard phosphorous level of 16 micrograms per liter.
Nitrogen standards were exceeded at Haycraft Park, Kihei Canoe Club beach, Mai Poina Oe Lau, Kalepolepo North, Kihei South (Lipoa), Kalama Park, Cove Park, Kamaole Beach I and III, Ulua Beach, Palauea and Makena Landing.
Hui O Ka Wai Ola is co-managed by Maui Nui Marine Resource Council, The Nature Conservancy and West Maui Ridge to Reef Initiative. The program also collaborates with the state Department of Health Clean Water Branch.
The goal is to gather enough information to provide remedies to the problem of coastal pollution. More testing and fundraising is necessary, which will help indicate whether the pollutants are from wastewater or fertilizer, said Tova Callender, coordinator of the West Maui Ridge To Reef Initiative.
“You can’t manage anything until you’ve measured it,” Callender said. “The point here is that it’s informing decision making.”
The core of the program is the 40 or so residents who volunteer with Hui O Ka Wai Ola. They go through a training protocol in order to help collect, monitor and analyze water samples.
“While it’s wonderful to have the distinction as citizen scientists as the very first in the state of Hawaii to be doing this water quality monitoring, we don’t want to be the only one,” said Callender. “The hope is that this can be replicated on other islands all over the state.”
The Hui O Ka Wai Ola team, also known as the Clean Ocean Team, has been taking samples in South Maui for over a year to test water quality along the coast from Makena to Haycraft Park in Maalaea.
Data on the amounts of sediment, nutrients and other pollutants from land-based sources entering the ocean are collected every two to three weeks. The Hui team tests for 13 water quality parameters, including ocean salinity, pH, temperature, organic nutrients, dissolved oxygen and turbidity, said Kim Falinski of The Nature Conservancy and the quality assurance officer for the team.
Samples are extracted in knee-deep coastal water.
The Health Department requires 30 samples be taken over a two-year period for the data to be considered valid, Falinski said. Labs on Maui are used, but some samples are sent to Oahu for more advanced analysis, she said.
It costs about $300 a month to monitor one site. One lab test for one water quality sample is $50, which is why Hui O Ka Wai Ola relies on donations and funding from the community, local businesses and the county, Callender added.
Coming soon, the team hopes to begin testing for bacterial parameters, like enterococcus and clostridium, which could indicate the presence of fecal contamination and can make people sick, Falinski said.
“It’s not easy to test bacterial parameters that could directly affect humans,” she said. “I don’t think we’ll be doing this right away because it requires advanced procedures, but if we did get really high in enterococcus, we might ask the Department of Health to come test for clostridium at the same time.”
The team does not measure for heavy metals, pesticides, radiation, sunscreen chemicals and pharmaceuticals because they are difficult to detect and require advanced equipment and procedures, which are costly.
“The quality of our water equals the quality of our life,” said Alana Yurkanin of The Nature Conservancy and the communications and safety coordinator for the Clean Ocean Team. “By monitoring water quality, consistently over a long period of time, we can identify those factors that are long term impacting human health and reefs.
“We focus on coral reefs because they are our predominant habitat in our nearshore water.”
Callender said that “it’s going to take an army of many to actually address the issues that we are seeing coming up.”
“We’re doing this because we love the islands,” she said.
To learn more about the program and its data and how to donate or volunteer, visit www.huiokawaiola.com.
* Dakota Grossman can be reached at firstname.lastname@example.org.