After deluge, climate change fears make S.Korea prioritise Seoul flood defences

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Experts say the city's capacity to drain water is far behind what's needed to handle a deluge like the one suffered this week. That has disastrous implications for low-lying areas like Gangnam, as these bouts of extreme weather are becoming increasingly common.

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In the wake of the downpour, Seoul Mayor Oh Se-hoon announced on Wednesday the city will spend 1.5 trillion won ($1.15 billion) in the next decade to build six massive underground tunnels to store and release rainwater to prevent flooding.

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The city's development meant increased pavement and impermeable surfaces, leading to higher runoff and more flooding. More than 50% of Seoul's land areas are impermeable, with the figure much higher in the affluent Gangnam district with wide boulevards and office buildings, experts said.

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Seoul had lacked any detailed plan for water control as it grew from a city of 2 to 3 million people in the 1960s to one with over 10 million by the 1990s, Moon said.

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