Posted on November 13, 2023
As Maui grapples with the trauma of the August fires and tries to envision the future of Lahaina, the mission to rebuild is complicated by a major obstacle: the contamination of the drinking water system.
When fires tore through the town on Aug. 8, the heat melted pipes, polluting the water inside with toxic chemicals. Officials are now testing for contamination property by property. Early testing has already exposed the presence of the carcinogen benzene and other chemicals but officials are only starting to understand the scope of the problem. They haven’t widely sampled the core of the burn zone.
Testing will be followed by a mass flushing of the system until the water runs clean. Approximately 2,200 service lines were impacted and may need to be replaced.
Restoring the system could take two to three years and could hold up redevelopment efforts, according to John Stufflebean, the director of Maui County’s Department of Water Supply who based the estimate on other comparable wildfire disasters.
“People wouldn’t be able to live there until the water system is back in place,” he said. “In other cases, that was the limiting factor, getting water back into the areas.”
Waiting that long to rebuild will be “disastrous” for Lahaina families who will probably, in the meantime, have to pay the mortgages on their burnt properties as well as rent elsewhere, according to John Sarter, whose Puapihi Street rental property burned down in the blaze.
“I worry a lot of the families that have been here for generations are just going to give up,” he said. “If people get delayed two to three years, they’re going to go bankrupt.”
Sarter, a longtime general contractor, is hoping the restoration of the water infrastructure can happen in tandem with rebuilding efforts. He would like to see residents return to their land as soon as possible, perhaps in tiny homes on wheels, so that they don’t have to pay double housing costs. As for water access, he wonders if tanks can be brought in as a temporary measure until the permanent system is restored.
“There is no reason it can’t happen concurrently,” he said.
Either way, bringing the water system back into service won’t be cheap.
A rough estimate is approximately $80 million, Stufflebean said. That’s the size of his entire annual budget, although he is hoping the Federal Emergency Management Agency will help foot the bill.
Ultimately, though, county taxpayers, and perhaps even Lahaina property owners themselves, will bear some cost for cleaning up the mess so clean water can once more flow through their taps.
Assessing The Damage
Before the fire, Lahaina’s water distribution system was pressurized with water that was pumped from several sources – a nearby stream and several wells – and through underground water mains, meters at the edge of properties and finally to faucets.
During the August fire, aboveground fixtures and pipelines melted, allowing water to leak out and depressurize the system. That created a vacuum effect in which contaminants from the melted pipes and other plastics on the property were sucked backwards into the pipes, Stufflebean said.
After the fire, crews closed off those open pipes to re-pressurize the system so that water could be used in the event of another fire, Stufflebean said. But now work has to be done to assess the type and scope of the damage to the pipelines and of the contamination.
The county is actively collecting samples and sending them to labs to determine if toxins are present. But exactly which chemicals to test for is a matter of debate.
One of the main concerns is volatile organic compounds which tend to migrate from liquids and stick to solids, like the walls of pipes. These so-called VOCs include substances known to make people sick like acetone, benzene, naphthalene, styrene, toluene and xylene.
However, there are no federal laws mandating which chemicals utilities must test for after a fire, according to Andrew Whelton, a Purdue University engineering professor and one of the nation’s foremost experts on contamination after wildfires.
Based on his research, Whelton recommends testing for a slate of 55 chemicals. He shared his advice with Maui early on under a county contract with Purdue and has offered to continue to assist local officials.
“You can’t just look for things that are convenient or that you heard about,” he said. “You have to tether the decision-making to evidence.”
But Maui isn’t testing for all the chemicals on Whelton’s list, according to its sampling plan. Stufflebean said the county is following the lead of the U.S. Environmental Protection Agency and the Hawaii Department of Health.
“These are our regulatory agencies,” he said. “The EPA has sent us their top experts on fire impacts on water systems.”
Also not in the county’s sampling plan are the “forever chemicals” known as PFAS. These perfluoroalkyl and polyfluoroalkyl substances are ubiquitous in the kind of consumer products that burned in the fire. PFAS are also common in firefighting foams, although the Maui Fire Department said its foam doesn’t contain them.
The EPA this year proposed regulations indicating PFAS chemicals are dangerous at minuscule levels, and there is widespread evidence the toxins have contaminated drinking water across the country.
“It’s definitely a concern,” said Chris Shuler, an assistant hydrologist for the University of Hawaii Water Research Center.
Making matters murkier, many of the potential contaminants in West Maui’s water don’t have specific regulatory limits, Whelton said. How much is too much is a matter of opinion, he said, and oftentimes safety will be in conflict with cost.
“Just because it doesn’t have a regulated limit in drinking water does not mean that the exposure to that chemical is safe at the level that they find it,” he said.
Separate from the county’s efforts, UH is also offering to test water lines for contamination free of charge. Testing requests can be submitted on the program’s website.
Flush And Repeat
Once contamination is identified, the pipelines will be flushed with water and tested again until they yield clean results.
Depending on the level of contamination, the flushing process may be quite water-intensive, according to Whelton.
“Let’s say it was 20 parts per billion of benzene,” he said, citing research done after the deadly wildfire in Paradise, California. “If you wanted to bring that contamination down to a level that never, ever gets above 0.5, you would have to flush that pipe for 195 days, seven days a week, 24 hours a day at one gallon a minute.”
That would be a high cost for Maui, which is already experiencing drought conditions and water shortages.
At a certain point, it’s likely worth replacing the contaminated pipes altogether, Whelton said. A lower level of benzene, say 2 parts per billion, would require an estimated 64 days of continuous flushing to bring it down to a level that is near zero.
The flushed water will be pumped into tanker trucks and delivered to a wastewater treatment plant, Stufflebean said.
Already, Maui County has cleared all areas of upper Kula that were initially put under an unsafe water advisory. The hard part will be Lahaina.
While the county has cleared some surrounding areas that were less impacted, officials have not widely tested the worst-burned areas, according to Stufflebean. The county is starting from the outskirts of Lahaina and working its way in, hoping to clear areas, zone by zone.
Gaudencio Lopez, chief of the Hawaii health department’s safe drinking water branch, said this water contamination event differs from the disaster at Red Hill on Oahu, where fuel flowed into the water system at a “singular point of entry.”
“Imagine that happening at thousands of potential locations within the distribution system,” he said. “And you don’t know where it happens. One location could be nondetect, the other neighbor’s line might have a detect. Another line might be super high.”
The testing is important for public safety but also to demonstrate the scope of damage to FEMA for future reimbursement.
Even after an area is cleared, Stufflebean said, the county will continue to monitor the water quality.
So far, the county has observed that water mains buried several feet down seem to be OK, but service lines to homes and businesses are damaged.
“It’s going to be a combination of renovating the existing system and replacing a lot of it,” Stufflebean said.
The water distribution system aside, contamination to the area’s groundwater must also be considered.
One bit of good news is that the water sources that feed into the Lahaina distribution system were unaffected, Stufflebean said. The town gets its water from wells and streams mauka of town.
“If there was contamination in the aquifer, it would not flow toward our wells,” he said.
The bad news is that contamination from Lahaina’s soil may sink into the groundwater under the town, according to Xiaolong “Leo” Geng, an assistant professor at the UH Water Research Center who has begun to research the extent to which that is happening.
Over the course of years, toxins may seep into the coastal waters around Lahaina, threatening the potential of recreation and tourism in the area.
“A lot of research needs to be done in this area so we can better understand the subsurface process,” Geng said.
Looking Forward
While the county and federal government may shoulder the bulk of the cost, individual property owners in Lahaina may have to pay more to keep the community’s water clean in the future.
While the Department of Water Supply is responsible for the water quality within the distribution system, its kuleana ends at the water meter. Between the meter and the faucet is the homeowner’s responsibility. If the homeowner’s pipes are contaminated, toxins could backflow into the distribution system, threatening the entire community.
Whelton is encouraging Maui to require property owners to test their own service lines on their side of the meter and to install backflow prevention devices. Those are expensive – about $2,000 to $4,000 a piece, Whelton said – but governments can offer subsidies. In Paradise, California, property owners can pay about $165 for installation plus monthly maintenance fees.
How the water system is rebuilt will also depend on the vision for the town’s future, Stufflebean said.
“If they make changes for whatever reason, the water system may have to have different sized pipes, different locations,” he said. “So we kind of have to wait on some of this until decisions are made about how the town is going to be rebuilt.”
In the meantime, the county is considering how the water system could be restructured to be more resilient to fires. The typical urban water system is designed to flow for two hours to put out a fire on maybe four or five structures, Stufflebean said. In Lahaina, 2,000 structures burned for hours and hours, and as water leaked out, hydrants ran dry.
“I would prefer not to rebuild it as it was,” Stufflebean said.
One possibility is expanding the number of water sources that feed into the system so that if there is a fire, there is less leakage, Stufflebean said. This could include the desalination of ocean water. There also needs to be a renewed focus on recycling water and conservation, he said.
Whatever upgrades occur, the county can’t necessarily count on the federal government to cover the entire cost. FEMA can assist with bringing the system up to the current code. But if improvements are made, reimbursement is limited.
“You can estimate the cost to replace and use that money to build something different with FEMA approval,” Stufflebean said. “Beyond that, FEMA can approve additional funds up to 15% of the (replacement cost) for ‘mitigation’ which can be used to mitigate against the cause of the fire.”
To explore the possibilities, the county has hired a consultant, Carollo Engineers, and other contracts are awaiting funding approval, according to Stufflebean.
“The hardest part is it’s going to take a while,” he said. “There is going to have to be some patience.”