Crews are battling rapidly spreading fires across Los Angeles, but their efforts have been repeatedly hampered by low water pressure and depleted fire hydrants. These problems exposed vulnerabilities in urban water systems that experts say were not built for wildfires of this magnitude.
Martin Adams, former general manager of the Los Angeles Department of Water and Power, said the water system that serves the neighborhood doesn’t have the capacity to deliver that much water over several hours.
“This system was never designed to fight wildfires that involve communities,” Adams said in an interview with the Times.
Limits in the local water system have left many fire hydrants in the Pacific Palisades with little or no water, as well as various public utilities, where firefighters say they are struggling with low water pressure. Firefighting efforts are complicated in Altadena and Pasadena.
Adams said the local water system in the Palisades area is designed to flow enough gallons per minute to extinguish residential fires and fires in apartments and commercial buildings. “Then you have massive fires across the region, with 10 times as many firefighting units pumping water out of the system at once.”
When wildfires occur, Los Angeles firefighters often use aircraft to drop water and flame retardant.
But as the blaze spread rapidly on Tuesday and Wednesday, Santa Ana’s extremely strong winds forced authorities to temporarily suspend water-dropping helicopters and forced crews to rely more on limited water systems on the ground. .
To assist, city officials dispatched tanker trucks to provide water to crews in areas with limited water supplies.
DWP CEO and Chief Engineer Janice Quiñones said the firefighting efforts had put the area’s water system under enormous strain, with demand for water four times the normal amount in 15 hours and “the system being pushed to the brink. He was forced into a situation.” She said the hydrants rely on three large water tanks, each holding about 1 million gallons. Fire hydrants used to work at lower elevations, but in hilly areas like the Palisades Plateau, where water is stored in storage tanks that flow by gravity to the areas below, hydrants run dry. I did it.
DWP and city leaders have faced criticism not only from residents but also from developer and former mayoral candidate Rick Caruso, who blamed “mismanagement” and aging infrastructure.
But water researchers said infrastructure limitations are a common feature of many urban water systems.
“Regional water systems are typically designed to fight small, localized fires for limited periods of time,” said Kathryn Sorensen, director of research at Arizona State University’s Kill Water Policy Center. “They are generally not designed to fight large, long-lasting wildfires.”
This limitation raises several questions. As fires grow larger and more intense in the Western world, should storage tanks and other local water infrastructure be expanded to combat the fires? Where? How much does it cost?
Sorenson said utilities need to consider how much water storage capacity to develop in peri-urban areas.
“Given the known risk of wildfire in these foothills, it is natural to question whether we should have added more reservoirs in previous years and months,” she said. say.
Los Angeles’ existing water system has “severe limitations,” said Gregory Pearce, director of the UCLA Water Resources Group. “You can’t really expect a system like the DWP to be prepared for this, at least not the way we’ve always wanted to build our systems and pay for them.”
The scale of the fire exceeded previous fires in Los Angeles. The Palisades Fire spread rapidly, destroying more than 5,000 homes and other buildings, and the Eaton Fires in Altadena and Pasadena destroyed an additional 1,000 homes and other buildings.
The cause of these and other fires is under investigation.
The wildfires occurred after a sudden change in weather from wet to extremely dry, a climate whiplash phenomenon that scientists say increased the risk of wildfires. Research shows that human-induced climate change is making these rapid wet-to-dry transitions more frequent and intense. Scientists have found that global warming has contributed significantly to the large and intensifying wildfires in the western United States in recent years.
The DWP, which sent a water tanker to help firefighters, said the intensity of the fire had disrupted its emergency response plans. Utility crews had limited access to three storage tanks on the Palisades, and DWP crews had to be evacuated as they tried to reroute water to refill the tanks. There were also, officials said.
DWP is reminding all customers, especially those on the Westside, to conserve water to prioritize firefighting supplies.
In Altadena, firefighters encountered similar problems due to low water pressure as they tried to slow the spread of the Eaton Fire. Pasadena Fire Chief Chad Augustin said the water system was overused as a result of having dozens of fire engines battling multiple blazes.
“In addition to that, there was a temporary power outage that affected the system,” he told reporters on Wednesday.
But even if crews had more water, “we couldn’t have stopped the fire last night because we had those gusty winds,” Augustine said. “Those erratic wind gusts carried the embers miles beyond the fire, which actually caused the fire to spread rapidly.”
He said such water restrictions are to be expected when such large-scale wildfires occur in urban areas.
“It’s common for cities to have fires this big and take up so many resources. We’re going to tax the water supply and the water system,” Augustine said. “And if there is a loss of power that could affect the pressure, the situation would be even worse.”
Firefighters radioed in about a problem with a hydrant Tuesday night, just hours after the Eaton fire broke out.
“We’re experiencing water issues pretty much east and west and the entire north end of the fire,” one firefighter said over the radio.
“We’re getting water for our work,” the dispatcher replied.
The problems firefighters reported in parts of Altadena occurred in areas served by two small supply companies: Rubio Cañon Land and Water Assen. and Lincoln Avenue Water. Representatives for these suppliers could not be reached for comment.
The Eaton Fire occurred in an adjacent area served by the Kinneloa Irrigation District, and the blaze caused minor damage to a generator, which has now been repaired, said Tom Majik, the district’s general manager.
Despite the damage, the district used backup generators and borrowed water from Pasadena Water and Power to provide water for firefighters, Majic said.
“All the pumps were running,” he said. “We were pumping water throughout the event.”
He said the district’s success in keeping water flowing is due in part to lessons learned from the 1993 Kinelloa fire. Firefighters were unable to receive water during the fire due to a lack of generators and power outages. This time, he said, his district had systems in place for emergencies. However, he added that infrastructure limitations had caused problems in other areas as well.
“To fight wildfires, we need to have Lake Havasu behind us,” he said. “Even if you fill the rose bowl with water, it’s not enough water.”
“There is no system that can do that,” he said.
Topography is also a factor in areas where water is pumped from the valley floor to storage tanks on hills.
Sorensen said similar limitations exist for water utilities that serve areas with large elevation differences. An engineer plans a water supply system with pressure zones at 100-foot elevations. For example, places like the Pacific Palisades rise more than 1,500 feet above sea level.
Sorensen said the city of Phoenix supplies water to a vast area with many hills and mountains, and there are nearly 80 pressure zones.
“Phoenix’s largest pressure zone is huge and its storage capacity is such that Phoenix can fight multiple fires for very long periods of time without running out of hydrant pressure,” she said. “Other pressure zones are very small, serving only a few customers, sometimes less than a dozen customers. Storage in these pressure zones will be much smaller, with multiple small residential There may not be enough stored water to fight the fire.”
Sorensen said that while infrastructure investment decisions are often driven by population, wildfire risk in hilly areas is another factor utilities should consider when building water storage infrastructure. said. In the Los Angeles area, “it would be very expensive to develop additional storage sufficient to mitigate or even extinguish wildfires in these high-elevation pressure zones, but at this time most people in Los Angeles I think so,” she said. It was worth the cost. ”
Pearce said investing in local infrastructure to expand firefighting water capacity in the Pacific Palisades could be an option if area residents were willing to pay the high investment costs.
“It’s going to cost a lot of money,” he said. He added that such additional water storage may not have been able to stop a fire of this size and intensity anyway.
Pearce said these types of water problems have occurred in past fires in Malibu and other areas, with firefighters encountering dry hydrants and using pools or draining water from the ocean. He pointed out that he had decided to pump the water.
“Is there a short-term future where we can or should do more, or a long-term future where we can think about doing more at incredibly high costs?” Pearce said. “Is there a future for them? Those are things that are on the table,” Pearce said.
Adams, a former DWP general manager, said the gap between what L.A.’s water system was built for and the rapidly evolving risk of large-scale fires is widening.
“The urban interface is changing, and we designed for a classic fire rather than a wildfire blowing through a community,” Adams said. “We need to think about fire protection and what firefighters really need if this is the future and we have a wildfire in our community.”
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