When wildfire strikes, water infrastructure that’s made out of plastic is particularly at risk of contamination. If pipes and tanks lose pressure, or get hot, chemicals can leach into the water supply.
The CZU Lightning Complex Fire badly damaged seven and a half miles of water supply lines made of polyethylene, a plastic, in northern Santa Cruz County.
That triggered the San Lorenzo Valley Water District, State Water Resources Control Board, and Santa Cruz County Health Department to issue a Do Not Drink - Do Not Boil water advisory for over 3,000 households in Northern Santa Cruz County in late August.
That advisory has now been lifted for a majority of homes in the area, and according to the District and State Water Board, the water is safe to drink again in those places that are cleared. Still, residents are wary.
“Basically, my biggest concern is my one and half-year-old son,” Bodgan Marian told KAZU.
Marian lives in a Boulder Creek neighborhood where authorities have declared the water clean and are continuing to take drinking water samples.
“As far as brushing my teeth and drinking the water, I think a lot of the neighbors that I spoke to here are going to air on the side of caution,” Marian said. “Just wait a little bit because these samples have to be repeated.”
“It's been an ongoing anxiety issue,” said Jeff Breen, another Boulder Creek resident who continues to use bottled water. “It was so unclear as to, you know, is this safe? So we're still using bottled water to cook with and wash our teeth with and so forth.”
Until more data comes in, Breen and Marian both said they’ll continue to use bottled water.
In the Riverside Grove neighborhood of northern Santa Cruz County, benzene has been detected in drinking water at levels that exceed state and federal standards. In at least one sample, benzene was detected at over forty times the State Water Board’s drinking water standard. According to the Office of Environmental Health Hazard Assessment, a branch of the California Environmental Protection Agency, people exposed to the contaminant for a period of a year to years could be at risk for health issues, such as cancer.
As of Sunday, the Riverside Grove area was still under a Do Not Drink-Do Not Boil water advisory. The neighborhood is about a mile away from where Marion lives. That’s one reason why he’s decided to sample his own tap water for contaminants. He’s working with a private lab and said the sampling has cost him about $400 so far. That cost, he said, is worth it to hopefully get peace of mind.
“I just don't know,” Marion said. “I'm not comfortable, and until I know, I'm not going to drink from the water.”
“I think it comes down to trust number one,” said Andrew Whelton, an associate professor and researcher in civil, environmental, and ecological engineering at Purdue University. After the Camp Fire raged through the region, Whelton worked with local, state and federal agencies to clean up water contamination in Butte County.
According to Whelton, the agencies involved in the response to the CZU Lightning Complex Fire should have issued an order that barred the use of any water in impacted Santa Cruz County neighborhoods.
Instead, the State Board and the San Lorenzo Valley Water District updated notices as time went on. In the original advisory, residents were not explicitly told if bathing and showering were safe, or not. A notice released a week later instructed residents to keep showers lukewarm or cold and short and to refrain from taking baths. Whelton says this type of messaging is confusing.
“Allowing people to bathe in that water and then coming out later finding contamination and telling people we shouldn't have let you bathe in it, and don't bathe in it any more, it undermines the whole credibility of the response,” Whelton said. “So I can't blame people for feeling uncomfortable about water safety after seeing something like that happen.”
Until more drinking water sample results come in, Whelton said the San Lorenzo Valley Water District and the State Water Board should take a more protective approach.
“The detections of benzene may indicate that there actually is a more pervasive problem in the system. Or it may be that this is an isolated incident,” Whelton said. “Regardless, it is an indicator, a red flashing warning light that something is terribly wrong with the water system and people should not be exposed to that water until its safety can be appropriately determined.”
Benzene is one contaminant of many in the Volatile Organic Compound class; these types of chemicals often show up in water systems after wildfire, Whelton said. But until the Tubbs Fire hit in 2017 not much was known about fire-linked water contamination.
This type of contamination isn’t an isolated problem. Santa Cruz County advised those with private wells and water systems to not use their water at all if any infrastructure could have been damaged in the CZU Lightning Complex Fire. The 580 households served by the Big Basin Water Company are under a do not drink water advisory where water infrastructure was also damaged in the CZU Complex. Testing is currently underway. North, in Napa County, the community of Berryessa Highlands has also been put under a Do Not Drink-Do Not Boil water Order as a result of the LNU Lightning Complex Fire.
In northern Santa Cruz County, the San Lorenzo Valley Water District is continuing to take samples in areas where water advisories have been lifted and in areas where the advisories persist, Stefan Cajina, the North Coastal Section Chief with the State Water Board’s Division of Drinking Water told KAZU.
“The other zones that are still under notice… we have not been seeing that same contamination and we keep looking for it and we keep not seeing it,” Cajina said. “I think we have, even after just a few weeks, a fairly good idea of what parts of the system are still at risk and the level of risk that they're under.”
There are steps water utilities can take to protect their infrastructure and communities against wildfire-linked contamination, Whelton with Purdue University said, including burying plastic water lines underground so risk of damage is less likely. But that work is often costly and takes time when utilities and people are trying to get water service back online as quickly as possible, he added.
That’s the challenge currently playing out in the San Lorenzo Valley Water District.
“The only way they're going to be able to restore that water supply quickly is probably by putting more plastic pipe back on the surface,” Cajina told KAZU. “And, yeah, you know, it’s a risk. It's not ideal.”
The district is facing an estimated $12 million in repair costs.
In the face of climate change linked megafires, Whelton said more communities are becoming vulnerable to this type of water contamination.
“This will be here for a very long time,” Whelton said. “And it is incumbent upon those state and federal and local officials to act based on evidence and protect the health and safety of the people that they are to serve.”