The fires in Los Angeles have created another problem – safe drinking water

Pressure drop, another major contributor to pollution, occurs when firefighting efforts draw large amounts of water from the system for a short period of time. “A water line connected to a house can generally put out about 9 gallons per minute,” Welton says. “Firefighters can pump 500 gallons or 1,500 gallons of water a minute. So if you take five or six pumpers out of the water line, you’re looking at thousands of gallons of water being removed from the water system in a very short period of time.

When this happens, the water pressure drops and the system becomes vulnerable to bacteria or chemicals entering the system from the environment. Typically, the high water pressure within the system prevents any external contaminants – such as soil or groundwater – from finding their way into the system’s components.

Whelton says structural damage from fires can also result in pressure losses. In the case of large-scale fires, such as the Palisades or Eaton fires, large volumes of water can spill out of the system in an uncontrolled manner due to burst pipes and other parts of the system. Where there is damage, smoke and debris can be drawn into the water system, and damaged sewer lines can leak into nearby drinking water pipes. “When the water utility tries to restore pressure, they start pushing the contaminated water back through the infrastructure,” Whelton says.

During the 2021 Marshall Fire in Louisville, Colorado, which burned more than 1,000 homes, city officials advised residents to use mains water only for washing until extensive testing confirmed its safety. Given that more than 12,000 structures were burning in Los Angeles on Monday morning, the potential for widespread contamination is significant, Kearns warns.

The coming days and weeks will be decisive. After assessing the damage, water experts will determine if the system can be cleaned or if infrastructure repairs are necessary. If it’s burned enough, workers will have to replace pumps, pipes and even tanks. For parts of Los Angeles County served by LADWP, McCurry estimates that recovery could take days to weeks.

However, Altadena and surrounding areas are served by many smaller water suppliers Lincoln Avenue Water Company, Las Flores Water Company, Rubio Canon Soil and Water Associationand Kinneloa Irrigation District— all of which issued “Do Not Drink” notices. “In the case of a large water system like LADWP, you’re probably going to see things move a little faster,” Kearns said. “Sometimes there can be some challenges for smaller water providers who may have a few employees and don’t have the budget for these types of measures.” Santa Cruz faced similar challenges during the 2020 CZU Lightning Complex fire, which took months to stabilize water service. McCurry cautions that in some regions, it could take years to build from scratch or overhaul large systems that have burned out.

It’s important for residents to be aware of recovery efforts because warning systems can be complicated and many residents may not be receptive to them, Kearns says. People should “proactively seek any boil or do not drink warnings from your water provider, city, region,” it advises. “Share them with your neighbors and make sure anyone whose first language is not English receives these warnings and understands what’s going on.”

Some places, such as Louisville in Colorado and Maui in Hawaii, have released public access maps that track water quality in each plot of land, helping to keep residents informed for months and years to come.

Before lifting advisories, the state of California legally requires water suppliers to test for the presence of benzene. However, Whelton cautions that benzene is not the only chemical of concern, and the list of potential contaminants is long. Both government and third-party testing services do not always account for possible exposures. “It’s possible that some of these chemicals will be around longer than water providers expect,” echoes McCurry. He still advises vigilance. Activated carbon filters can help remove some organic contaminants, but may not completely eliminate the risks.

“Safe water can It can be rebuilt after a fire,” Whelton says. “Communities that recover faster and stronger are those that work together and support each other.”