River valley is a strip of zone in which the natural cream and numerous human landscapes are congregated.In Taihang mountain areas of Hebei province,river valley occupies only about 10 percent of the total area of mountain and hill region,but it gathers almost all the inhabitant construction land and farmland with the highest productivity level.River valley holds the key position in sustainable development strategy in the areas.On 4 th and 5 th August 1996,a great flooding rarely in the local hist...