Future Floods May Test Tokyo's Defenses

Despite the presence of a formidable (and expensive) underground flood control system, Tokyo may confront floods and rainfall that will challenge the city's capacity to protect itself.

1 minute read

October 24, 2017, 1:00 PM PDT

By Philip Rojc @PhilipRojc


Rainbow Bridge

i am way / Shutterstock

As the threat of flooding remains on the minds of many here in the United States, citizens of Tokyo face their own set of worries. Hiroko Tabuchi discusses the city's Metropolitan Area Outer Underground Discharge Channel, a "$2 billion underground anti-flood system, completed in 2006, [that] is an extraordinary example of the defenses that global cities are readying as they face an era of extreme weather brought on by climate change."

While the system is impressive, concrete infrastructure may not be enough to hold back what climate change has in store. Leading up to the 2020 Olympic Games, concerns are mounting. Tabuchi writes, "But now, with a government debt more than twice the size of its economy and spiraling costs of caring for an aging population, the country is less able to muster the resources to fund such ambitious projects."

Some experts also argue that more extensive protections, if built, "only encourage development in regions that could still be vulnerable to future flooding. [...] Investment in infrastructure need[s] to be paired with more public education in disaster survival skills, like familiarity with local flood hazard maps or evacuation protocols."

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