UH researchers investigate nearshore water quality, reef health after Maui fires  

UH Mānoa students prepare water samplers for deployment at Mala Wharf. Photo credit: Andrea Kealoha

Preparing sampling materials for shoreline water testing in Lahaina. Photo credit: Andrea Kealoha

Nick Hawco prepares materials for trace metal sampling. Photo credit: Andrea Kealoha

A team of researchers from the University of Hawaiʻi at Mānoa are sampling West Maui reefs to assess the impact from the toxic ash from the devastating Lahaina wildfire. More than 2,200 structures were destroyed in the fire including gas stations, power lines and numerous boats in the Lahaina harbor. The adjacent coral reef ecosystems possibly impacted by the fire support subsistence, recreational and commercial fishing, particularly for the large Native Hawaiian population.

The UH team is working collaboratively with the community and county, state and federal experts to identify the pollutants and assess their abundance and ultimately determine if they will alter the ecosystem and affect its resilience in the future. The team was awarded a rapid response grant from the National Science Foundation (NSF) to study the immediate impacts from the contaminants created by the fire. 

“We are measuring a number of water quality parameters, but importantly, we are connecting water quality to metrics of reef health to understand how the ecosystem may respond to potential wildfire stressors,” said Andrea Kealoha, a new faculty member with the UH Mānoa School of Ocean and Earth Science and Technology (SOEST) Department of Oceanography who is leading the team. Kealoha lives on Maui and previously led the Water Quality Lab at UH Maui College.

She assembled a team of experts at SOEST, including Craig Nelson with the Center for Microbial Oceanography: Research and Education, Eileen Nalley with the University of Hawai‘i Sea Grant College Program (Hawai‘i Sea Grant), and Nick Hawco with the Department of Oceanography.  

The testing will identify the pollutants such as copper, lead and organic contaminants associated with burned materials, particularly wood and plastics.

The team is planning multiple sampling campaigns over the next year to document reef health and contaminant loads. While this grant focuses primarily on water quality and reef health, the team is also working to address specific community concerns about the potential accumulation of contaminants in reef fish. 

The health of the coral reefs and nearshore ecosystems are intimately tied to the overall health of the community, and as islanders with deep cultural and economic ties to the marine environment, there is virtually no separation between human health, ecosystem health, and the health of the nearshore marine resources that people rely on for subsistence, recreation, and commercial fishing.  

“We’re preparing for the first big rains this winter,” said Hawco, who was involved in a rapid response effort to the 2018 Thomas Fire in Southern California. “That’s when we expect much of the burned soils, ash, metals, and contaminants to reach the ocean and have the biggest impact on the reefs.”

The needs of the community and providing answers to critical questions around the future health of the environment and community are the top priority for researchers from the university and all of their collaborators on Maui, who are working together to serve the community.

“Collaborations are key with this effort,” said Kealoha. “There is no person, organization, or agency with all the expertise and resources to address these questions. We will continue to engage and communicate with partners in west Maui to ensure that knowledge from the community plays a role in guiding these research efforts.”

There are numerous partners and collaborators on this project, including the Department of Land and Natural Resources, the West Maui Watershed and Coastal Management program led by Tova Callendar, the Hawai‘i Department of Health, the UH Maui College water quality lab, Hui o Ka Wai Ola, the Pacific Whale Foundation, and members of the Lahaina community.