The inferno that swept through Lahaina town in August not only killed scores of people, but destroyed more than 2,200 buildings in an urban setting that typically holds heavy metals, stored chemicals and other potential contaminants.

What started out as a brush fire turned into a raging urban fire, leaving behind a toxic environment that, among other things, threatens to affect nearshore water quality and ecosystems.

“As far as I know, there’s never been an urban wildfire near a coral reef. That’s unprecedented,” said Andrea Kealoha, a faculty member with the University of Hawaii at Manoa Department of Oceanography.

Bolstered by a $200,000 National Science Foundation rapid-response grant, Kea­loha and a team of UH researchers are gearing up to sample the coral reefs near Lahaina to assess the impact of the toxic ash from the fire.

The scientists are preparing to mobilize for the first big rains this winter, when much of the burned soil, ash, metals and contaminants are expected to reach the ocean and have the biggest impact on the reefs.

Kealoha said other rural areas have experienced fires, and there are studies about the impacts on nearshore waters.

“We can use these other studies as indicators of what we can expect to see, but there’s no perfect analogy,” she said.

The team plans multiple sampling campaigns over the winter to document reef health and contaminant loads. The intensive chemistry and biological testing will feature the collection of samples every few hours over multiple days.

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

The project’s first sampling campaign actually took place a couple of weeks ago, with the results set to serve as the project’s pre-rain baseline.

The results are still out, as multiple labs need to run analysis of the samples. They might not be back for a period of weeks to months.

Visually, the reefs and the water appeared to be unaffected, Kealoha said.

”That doesn’t mean that there aren’t changes that are occurring that we can’t see. And so that’s why measuring the chemistry is so important,” she said.

The team has been preparing for what the scientists are calling “the first flush.” The plan is to mobilize the team of researchers quickly to deploy more sensors and collect more samples following the first big rain.

Nick Hawco, a UH Manoa oceanography colleague, is another scientist involved in the project. He was part of a rapid-­response team that recorded the ocean impact of the December 2017 Thomas fire in Santa Barbara and Ventura counties in Southern California.

The first rain in January 2018 brought lots of ash, black carbon and metals pouring into the ocean, he recalled.

Hawco said Hawaii’s nearshore ecosystems could be more vulnerable than California’s, in part because runoff from fires is much less common here.

In Lahaina the Environmental Protection Agency plans to spray cleared areas with Soiltac, a biodegradable soil stabilizer that will create a temporary crust over the ash. The material is commonly used for construction and industrial dust control, but its use in wildfire recovery is relatively new.

If it works, that could very well cut down on contaminants reaching the nearshore area, Hawco said.

“It’s totally possible that nothing bad happens (to the reefs),” he said. “But for now we don’t know, and it’s important to do this out of concern for the risk.”

Hawco said the project is lucky to have Kealoha as leader.

“She knows the area, and for this study her role is essential,” he said.

Kealoha was born and raised on Maui and is a graduate of King Kekaulike High School in Kula. She earned her Ph.D. at Texas A&M but moved back to the Valley Isle when she was hired in 2019 to build the Water Quality Lab at UH Maui College.

When Kealoha was hired as an assistant professor by UH Manoa’s Oceanography Department, her first day was Aug. 15 — one week after the disastrous fire.

The timing allowed her to tap into the expertise and resources of Hawaii’s flagship campus. In addition to Hawco, Kealoha recruited a UH Manoa team of experts that includes Craig Nelson with the Center for Microbial Oceanography: Research and Education, and Eileen Nalley with the UH Sea Grant College Program.

But orchestrating the effort has been a challenge, especially as access to Lahaina is limited, with many places needing special permission from multiple agencies.

“There are safety and health concerns around air and water quality, and we have a large group focusing on many aspects of reef and ocean health,” she said.

Kealoha said the project has a variety partners and collaborators, including the state Department of Land and Natural Resources, the West Maui Watershed and Coastal Management program led by Tova Callendar, the state 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.

While the grant focuses primarily on water quality and reef health, the team is also working to address community concerns about the potential accumulation of contaminants in reef fish.

“We’re not just asking questions about the science that we’re interested in. We’re doing this in response to what our community needs are,” Kealoha said.