The fires in Los Angeles created another problem – unsafe drinking water

Depressurization, the other big factor in contamination, occurs when firefighting efforts draw massive amounts of water from the system in a short period of time. “A water main that connects to a house can typically put out about 9 gallons per minute,” Welton says. “Firefighters can pump 500 gallons or up to 1,500 gallons of water per minute. So if you have to run five or six truckloads of pumps from a water main, you’re seeing thousands of gallons of water drawn from the water system in a very short period of time.

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

Structural damage from fires can also lead to pressure losses, Welton says. In the case of large-scale fires such as the Palisades or Eaton fires, you can have huge volumes of water released uncontrollably out of the system due to ruptured pipes and other parts of the system. When there is a failure, smoke and debris can be sucked into the water system, while damaged sewer lines can leak into drinking water pipes that run nearby. “When the water system starts trying to restore pressure, they start pushing that contaminated water through the infrastructure again,” Welton says.

During the 2021 Marshall Fire in Louisville, Colorado, which burned over 1,000 homes, city officials advised residents to use mains water only for flushing until extensive testing confirmed safety. Given that more than 12,000 buildings have burned in Los Angeles since Monday morning, the potential for widespread contamination is significant, Kearns warned.

The coming days and weeks will be decisive. After water experts assess the damage, they will determine if the system can be flushed clean or if infrastructure repairs are needed. If enough has burned, 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 anywhere from a few days to weeks.

However, Altadena and the surrounding regions are served by numerous smaller water suppliers such as Lincoln Avenue Water Company, Las Flores Water Company, Rubio Canon Land and Water Associationand Kineloa Irrigation District— all of whom have issued Do Not Drink notices. “In the case of a large water system like LADWP, you’re probably going to see things pick up a little faster,” Kearns says. “For smaller water providers, who may sometimes only have a few employees and don’t have the budget for these types of events, they may have some difficulties.” Santa Cruz experienced similar challenges during the 2020 CZU Lightning Complex fire. , with the water supply taking months to stabilize. McCurry cautions that some regions may require years to build from scratch or overhaul large systems that have burned out.

It’s vital that residents are informed about recovery efforts because warning systems can be complicated and many residents may not even receive them, Kearns says. People should “proactively look for any boil or Do Not Drink water alerts from your water supplier, your city, your county,” she advises. “Share them with your neighbors and make sure any people who may have languages ​​other than English as their first language get these alerts and understand 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 parcel, helping to keep residents informed in the coming months and years.

Before the warnings were removed, water suppliers were required by law by the state of California to monitor for benzene. However, Welton cautions that benzene is not the only dangerous chemical, and the list of potential contaminants is long. Both government and third-party testing services do not always account for every possible exposure. “It’s possible that some of these chemicals will linger longer than water suppliers expect,” reiterates McCurry. He still recommends staying vigilant. Activated carbon filters can help remove some organic contaminants, but may not completely eliminate the risks.

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