自然灾害是人类难以控制和不可抗拒的自然现象,时时刻刻都有可能发生,会给人类带来了巨大的经济损失和精神痛苦。据报道,全世界每年由于自然灾害所造成的损失约达300亿美元,其中纯损失200亿美元以上,年平均受灾人数4000多万人,死亡人数100多万人。并且随着社会的发展和人民生活水平的提高,有逐年增长的趋势。在各种自然灾害损失中,水灾损失约占 Natural disasters are natural phenomena that are beyond our control and irresistible. Human disasters are likely to occur all the time, bringing enormous economic losses and mental anguish to human beings. According to reports, the world each year due to natural disasters caused by the loss of about 30 billion US dollars, of which net loss of more than 20 billion US dollars, the average annual number of victims affected more than 4000 million, the death toll of more than 1 million people. And with the social development and improvement of people’s living standards, there is a trend of increasing year by year. In a variety of natural disaster losses, flood damage accounted for about