On July 20, water engulfed Zhengzhou’s Metro Line 5 station, capturing more than 500 passengers beneath the city for hours. The flash flood slowly filled the tunnel until many passengers were submerged chest deep. Countless people recorded the incident with shaking hands, utterly terrified by the quickly rising water levels. Help didn’t arrive until four hours later, and unfortunately, 11 people were lost in the accident.
Experts are still working out the exact explanation that caused the event but are certain that climate change played a large role. Liu Junyan, climate risk project leader in Greenpeace East Asia’s Beijing office, warns the rest of the world, “The intensity and frequency of extreme weather is increasing with climate change, [and] major metropolitan areas around the world are at increased risk.” Other scientists share the same views as Junyan, handing out warnings to specific areas like Hong Kong and New York, whose drainage systems aren’t efficient enough to handle a lot of water. In fact, not too long before the flooding of Zhengzhou’s subway, the London Underground experienced flooding in many of its stations as well. It is apparent that many cities aren’t aware of how at-risk their stations are to flooding, and are unequipped to handle such situations. This behavior is expected, as very little research has been conducted on how floods affect metro systems, but with climate change posing more and more threats, knowledge of these factors is becoming increasingly important.
Flooding in China is no surprise during the summer, however, the flood on the 20th was anything but expected and in that day alone, the amount of rainfall surpassed what was expected for the entire year. Although the province is well equipped to grapple with flooding, its drainage systems said to be able to deal with 100-year floods (floods that have a 1% chance of happening per year), the flood that struck was measured as a 1000-year flood and left the drains utterly useless. News of the event is giving many metropolitan areas time to rethink and restructure their metro systems. Until some effective action is taken to slow down the rates of climate change, and with it the intense increase in flooding, subway passengers should be more cautious when taking the subway on a rainy day.