It's more complex to program drainage plan in mountainous city .Now there are some changes in Chongqing, one of these changes is treatment wastewater from natural water sections to few centralized area. In this paper systems theory is adopted and many factors are combined with such as technology, economics, society and politics to discuss drainage project in main districts of Chongqing and draw a conclusion as the argument result. So the article suggests that it is necessary to collegiate argumentation with different point of views, differents subjects and different ranges. And it must be assured by law procedure.