永定河是北京的母亲河,是北京市重要水源地,是全国四大重点防洪江河之一。她孕育了中国的七朝古都,为世人留下宝贵的文化遗产。然而,上世纪80年代以来,永定河连续断流、生态退化、扬沙严重,甚至成为离北京城区最近的风沙源。同时面临着流域内水量减少、水质变差、河道生态环境恶化、防洪安全存在 Yongding River is Beijing’s mother river, is an important source of water in Beijing, is one of the four major flood control rivers. She gave birth to seven ancient capitals of China and left precious cultural heritages for the world. However, since the 80s of the last century, the Yongding River has been continuously shut-off, its ecology has deteriorated, and the sand has been gravely littered. It has even become the most recent source of sandstorms in urban areas in Beijing. At the same time, the water in the basin is reduced, the water quality is deteriorated, the ecological environment in the river is deteriorated, and flood control safety exists