LAHAINA, Hawaii — This seaside town is a scene of charred devastation. Block after block of blackened wreckage and ash. Many of the homes and apartments, restaurants and bars, surf shops and art galleries that populated this historic Hawaiian community have burned down to their foundations.

Hulks of blackened cars are visible throughout the town. Gas stations and propane tanks exploded and boats caught fire in the harbor over the course of hours as the town burned, according to residents who escaped the flames. The raging inferno sent toxic fumes and material spewing throughout the town and into the sea, and whenever the next big storm hits, it will flush even more contamination into local waters.

In and around Lahaina, there is still a strong smell of smoldering debris and chemicals in the air. Some of it comes from the abandoned vans and cars, their rims melted in puddles in the streets, as well as piles of twisted corrugated metal, scores of burned-out washing machines and melted weightlifting sets.

Even as the fire retreats, danger remains for Maui residents as they return to the charred wreckage of their neighborhoods. The fire killed more than 100 people as it raged last week. Helping families recover and continuing to identify victims is the immediate priority. But the toxic soot left after an urban conflagration is its own disaster upon a disaster, one that can linger long after the flames themselves have died.

"We are going from one natural disaster to the next," Newsha Ajami, a water expert at Lawrence Berkeley National Laboratory said of the post-fire contamination.

When fire consumes a community, it burns indiscriminately through products people need for everyday life — automobiles, home insulation, paint cans, plastics and pressure-treated wood. Those building materials contain lead, arsenic, asbestos and other dangerous chemicals that can go up in smoke and into lungs.

"These areas should be approached very carefully, very cautiously," state toxicologist Diana Felton told residents on Hawaii Public Radio.

Debbie Van Alstyne, an employee at the Plantation House Restaurant in Kapalua, said local air quality officials told her and other residents this week that they cannot expect to be back soon in their homes, even if they didn't burn, because the air is still dangerously contaminated.

"You can't have children playing out there. The air quality coming from front street with the winds, is deeply toxic with asbestos," she said. "He says that it's absolutely not safe for anybody to stay near there. For a while."

Jack Fisher, a musician and real estate broker up the mountain in Kula, watched the "gargantuan" flames last Tuesday from a distance in his car, running the air conditioner to filter out smoke. He tapped a stash of leftover N95 masks from the days of COVID to venture outside the next day.

"You could taste it. You could feel it," he said of the smoke. The fire spared his home but left a sooty mess near an open window. "We lucked out. I thought this place was going up in flames."

After fires, toxic ash and dust that has settled on the ground can be stirred back up into the air months later. And when rain finally falls on the drought-stricken island, it may wash the hazards downstream if not cleaned from the soil in time. Any contamination that goes down the storm drain can end up in the ocean full of surfers and sea turtles.

"If it's not cleaned up properly, it can be released to the environment in different ways," Ajami said. "Next rainfall, next storm potentially can wash it off to the ocean or actually impact the groundwater, depending on the location. So it's a big challenge."

Andrew Whelton, an engineering professor at Purdue, said dirt needs to be tested and possibly six inches of soil needs to be removed from contaminated sites. And storm drain interceptors should be deployed to reduce toxic runoff, he said.

"People are going back to their properties that may have destroyed structures and encountering hazards that could make them acutely sick if they're not protected," Whelton said.

Already there is evidence of fouled marine waters. During the first days after the fire, people delivering food and other supplies by jet ski said the Lahaina Harbor was nearly entirely covered by a fuel slick left by burned boats. With the harbor now cordoned off, it is difficult to discern how much of the slick remains, but the burned-out and sunken boats will take months to clear.

Wildfires can also contaminate people's drinking water, as overheated plastic pipes leach chemicals into a community's water delivery system. When such systems lose water pressure — as occurred in Lahaina when the power was knocked out — it can draw even more pollutants into the drinking water.

Since Aug. 11, Maui County has been warning residents in certain fire-scarred areas — mainly Lahaina and Upper Kula — about possible water contamination, urging them to avoid the tap for drinking, brushing teeth, making ice and preparing food. Right now, it is unclear what contaminants may be in the drinking water. Officials tested water systems in Lahaina and Upper Kula on Monday, shipping samples to Oahu for analysis.

State health officials are also warning those returning to the fire's footprint to cover themselves head to toe — with N95 masks, goggles, gloves, socks, pants, long-sleeve shirts and closed-toed shoes — to avoid contact with potentially toxic ash. As they clean up their properties, residents are being told to avoid vacuums or leaf blowers that will push ash back into the air.

"It just smells like absolute poison. It's not just like a campfire smell. It's just in the air. And it feels dirty to breathe," said one Kula resident cleaning up her neighborhood. She spoke on the condition of anonymity to protect the privacy of her family after the fires.

"When you're up there working in the community and volunteering with your neighbors, there's just soot in your hair. You're filthy," she added.

Children in particular need to keep away from rubble, officials warn, in part to avoid lead exposure. Even low levels of lead in blood can impede a child's performance in school and lead to irreversible brain damage.

With many burned neighborhoods still behind police lines, a top pollution priority is getting safe drinking water to people. For now, many residents have resorted to drinking bottled water that is available in pallets at the aid stations in Lahaina and elsewhere along the coast within the security cordon. Earlier this week, residents said small airplanes traversed the coast warning people not to drink the water.

Whelton said officials need to go further with their do-not-drink advisory and tell residents to stop bathing with the water, too. He has seen just how contaminated water systems can get after the Marshall Fire in Colorado and the Camp Fire in Paradise, Calif. He is making his way to Maui to assess the damage himself.

"I have contacted different agencies and urged them that that alert isn't protective enough," he said. "They do not know what's in the water."

While the situation is bleak now, recovery is possible for wildfire-ravaged towns, Whelton said. "It is possible to have a safe community again and to regain some sense of normalcy."

The Washington Post's Grandoni reported from Washington.

previous coverage

• Desperate families turn to sticky notes seeking missing Maui fire victims
• In the ruins of Lahaina, a surfing legend leads a volunteer army to get supplies to survivors
• In Maui, echoes of the deadliest US wildfire: the 1871 Peshtigo blaze

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