Pressure drops, another major cause of contamination, occur when firefighting efforts drain large amounts of water from the system in a short period of time. “A water line connected to a house can typically spew out about 9 gallons per minute,” Whelton said. “Firefighters can pump out 500 gallons or up to 1,500 gallons of water per minute. So if you run five or six water pump trucks off the water line, you will see thousands of gallons of water extracted from the water system in a very short period of time.”
When that happens, water pressure plummets and the system becomes susceptible to bacteria or chemicals entering the system from the surrounding environment. Typically, the high pressure of water inside the system prevents any external contaminants—such as soil or groundwater—from getting inside the system components.
Structural damage from fire can also lead to pressure loss, Whelton said. In the event of large-scale fires like the Palisades or Eaton fires, you may see huge amounts of water spill out of the system, uncontrollably, due to pipes and other system components being damaged. broken. Where there is damage, smoke and debris can be drawn into the water system, while damaged wastewater lines can leak into drinking water pipes running nearby. “When the water system company starts trying to repressurize, they start pushing that contaminated water through the infrastructure again,” Whelton said.
During the Marshall Fire in Louisville, Colorado in 2021, which destroyed more than 1,000 homes, city officials advised residents to use only tap water for flushing until extensive testing confirmed safety . Kearns warned that with more than 12,000 structures burned in Los Angeles as of Monday morning, the potential for widespread contamination is great.
The coming days and weeks will be crucial. Once water experts assess the damage, they will determine whether the system can be flushed or whether infrastructure repairs are needed. If there is enough fire, workers will need to replace pumps, pipes and even tanks. For areas of Los Angeles County served by LADWP, McCurry estimates this recovery could take from a few days to a few weeks.
However, Altadena and surrounding areas are served by many smaller water suppliers, such as Lincoln Avenue Water Company, Las Flores Water Company, Rubio Canon Soil and Water AssociationAnd Kinneloa Irrigation District—all have issued No Alcohol notices. “In the case of a large water system like LADWP, you might see things move forward a little faster,” Kearns said. “For smaller water suppliers, sometimes with just a few employees and not enough budget for these types of events, they can face some difficulties.” Santa Cruz experienced similar challenges during the CZU Lightning Complex Fire in 2020, with water service taking months to stabilize. McCurry warned that some areas may need years to rebuild from scratch or overhaul large systems that have burned.
It's important for residents to stay informed about recovery efforts, Kearns said, because warning systems can be complex and many residents may not even receive them. People should “proactively look for any boil water or Do Not Drink warnings from your water supplier, city, county,” she advised. “Share that information with your neighbors and make sure that anyone who has a language other than English as their first language receives those messages and understands what is happening.”
Some places, like Louisville in Colorado and Maui in Hawaii, have released public access maps to track water quality on a parcel-by-plot basis, helping to inform residents in the months and years ahead.
Before the advisory was lifted, water suppliers were legally required by the State of California to monitor benzene concentrations. However, Whelton warns that benzene is not the only chemical of concern and that the list of potential contaminants is long. Both government and third-party testing services do not always account for all possible exposures. “It's possible that some of those chemicals may persist longer than what water suppliers expect,” McCurry echoed. He still advises you to be vigilant. Activated carbon filters can help remove some organic contaminants, but they may not completely eliminate the risk.
“The water is safe Maybe restored after a fire,” Whelton said. “Communities that recover faster and stronger are those that work together and support each other.”