Flood-prevention management must be improved as global warming changes weather patterns
The devastation in central China over the past week highlights the urgent need to strengthen defences against the fury of nature
Central China’s heaviest rainfall in years is giving the Three Gorges Dam its biggest-ever test. Flood control systems along the Yangtze River are straining against the rising waters. Some have compared the deluge to that of 1998, the worst in recent decades which led to floods that killed at least 3,000 and left 15 million homeless. The death toll, number of evacuations and scale of the damage have so far been dwarfed by that disaster, but it is clear that not all local governments were well prepared.
Premier Li Keqiang (李克強) called for more strenuous efforts on Wednesday after arriving in flood-ravaged Wuhan (武漢 ) from neighbouring Hunan (湖南 ) province. The disaster relief work and emergency response mechanisms have generally held up well. But approaching Super Typhoon Nepartak risks worsening the floods. President Xi Jinping (習近平 ) has ordered the army and police to step up disaster alleviation efforts.
Authorities have been warning since March that unusually heavy rains were likely for July and August. Anti-flood embankments along the Yangtze were reinforced and monitoring systems strengthened. But weather forecasting is not an exact science. Global warming has altered rain patterns and increased the frequency of severe weather events. The mainland has spent tens of billions of yuan on infrastructure to control flooding over the past two decades, but the investment has not kept pace with the rapid increase in urbanisation.
The Three Gorges Dam remains as controversial today as when it was conceived in the 1950s. But there are limits as to its ability to control flooding: while it can do that effectively with waters coming from the upper reaches of the Yangtze, it can only play an indirect role when heavy rains fall downstream. Flood control mechanisms along the length of the river therefore have to be integrated and surveillance and monitoring systems ever-alert. Natural water systems have been disrupted by urban construction, but the latest flooding makes clear that there have also been failings in flood-prevention management.
