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The authority also has an emergency flood response.
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"We are investing more in water mitigation today than we ever have," says Andy Off, executive vice president of capital delivery for the Washington Metropolitan Area Transit Authority. In Washington, the transit authority has spent millions of dollars waterproofing leaky tunnels and plans to spend even more to keep water out of vents and station entrances. After Hurricane Sandy flooded miles of subway tunnels, New York poured millions of dollars into flood control for the nation's largest underground rail system. In Boston, the transit authority has started waterproofing stations and protecting tracks that are vulnerable to sea level rise. cities are a decade or more into adapting their subway systems to a wetter climate. "Looking ahead, authorities need to think very carefully about where they want to build new lines, new stations, new tunnels." "Every city should have a comprehensive review of flood risk for the underground system," Djordjevic says. The infrastructure bill moving through Congress allocates $66 billion for rail - a huge infusion of cash that could help fund retrofitting of old subway systems to keep water out and the building of new train lines in places that currently depend on cars. Some help could come from the federal government. Keeping water out of tunnels and stations is expensive, especially in places with aging, leaky subways built for a 20th century climate. That has created tension between the need to provide reliable, low-emissions mass transit options and the growing cost of maintaining underground transit in a wetter world. Dozens of subway systems around the world have experienced flooding, Djordjevic says, and he estimates it's likely hundreds of thousands of passengers have been directly affected. Earlier this summer, the remnants of a tropical storm dumped a month's worth of rain on New York City in the span of an afternoon. Zhengzhou received about a year's worth of precipitation in just one day. In China and around the world, the culprit is climate-driven torrential rain. "I actually considered whether this was even real." But he says what he saw happening in China shocked him. Djordjevic has spent much of his career studying floods in subway tunnels. "None of us had seen people with water up to their necks, standing in underground trains," says Slobodan Djordjevic, an engineer at the University of Exeter who specializes in flooding of underground train systems. Harrowing videos showed people struggling to breathe a shrinking pocket of air as the water rose. In July, 13 passengers died in Zhengzhou, China, after flash floods trapped them. subway station /uYemJKB8yg- Brian Kahn September 2, 2021Įlsewhere, subway floods have turned deadly. Our infrastructure is not ready for climate change, a thread from tonight.
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