(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.)
Andrew J. Whelton, Purdue University and Caitlin R. Proctor, Purdue University
(THE CONVERSATION) In recent years wildfires have entered urban areas, causing breathtaking destruction.
The 2018 Camp Fire in Paradise and Butte County, California was the deadliest and most destructive fire in California’s history. It took 86 lives and destroyed more than 18,000 structures in a matter of hours.
Almost two years later, only a fraction of the area’s 40,000-plus population has returned. This disaster followed the 2017 Tubbs Fire, which killed 22 people in California’s Sonoma and Napa counties.
After both fires, drinking water tests revealed a plethora of acutely toxic and carcinogenic pollutants. Water inside homes was not safe to use, or even to treat. Water pipes buried underground and inside of buildings were extensively contaminated.
We are environmentalengineers who help communities affected by disasters, and supported responses to both fires. As we conclude in a recently published study of burned areas, communities need to upgrade building codes to keep wildfires from causing this kind of widespread contamination of drinking water systems.
Wildfires and water
Both the Tubbs and Camp fires destroyed fire hydrants, water pipes and meter boxes. Water leaks and ruptured hydrants were common. The Camp Fire inferno spread at a speed of one football field per second, chasing everyone – including water system operators – out of town.
After the fires passed, testing ultimately revealed widespread hazardous drinking water contamination. Evidence suggests that the toxic chemicals originated from a combination of burning vegetation, structures and plastic materials.
Firefighting can accelerate the spread of contamination. As emergency workers draw hydrant water, they spread contaminated water through the water pipe network.
Metal, concrete and plastic pipes can become contaminated. Many plastics take up these chemicals like sponges. As clean water later passes through the pipes, the toxic substances leach out, rendering the water unsafe.
In the Tubbs and Camp fires, chemicals in the air may have also been sucked into hydrants as water pipes lost pressure. Some water system plastics decomposed and leached chemicals directly into water. Toxic chemicals then spread…