昆明市城市化发展对滇池入湖洪水的影响分析

A Study of the Impact of the Urban Development of Kunming City on the Dianchi Lake Flood Inflow Procedure

滇池控制运行水位的高低在一定程度上将影响到滇池水污染的治理效果,设计入湖洪水过程是滇池汛限水位和20年一遇防洪高水位制定的重要边界条件。随着昆明城市化进程的加快,一般认为滇池的入湖洪水会明显增加。就此问题进行了基础资料的调查、收集及定性与定量相结合的分析,研究发现昆明城市化进程对滇池入湖洪水的影响有限,在设计洪水过程分析中可不予考虑,原因是在滇池入湖洪水中湖面雨洪已占30%以上,城市建成区面积在滇池流域中所占比重不足10%,加上城区排水管网设计标准低,河道比降小,行洪能力低,减缓了城市硬化地面洪水汇流入湖的速度。

The Dianchi Lake＇s operational level influences its efficacy of pollution treatment to some extent,while the lake design flood inflow is an important boundary condition for setting the lower limit level for flood control and the flood control level for a 20 year ARI flood event.With the speeding up of the urban development of Kunming City,it is generally thought that there will be a significant increase in the Dianchi Lake＇s flood inflow.In order to verify this thought,this paper collects relevant basic data and makes a qualitative and quantitative analysis of this scenario and draws the conclusion that the urbanization of Kunming City exerts a limited influence on the Dianchi Lake＇s flood inflow and can thus be neglected in the design of the Dianchi Lake＇s flood inflow.This is a result of the combination of the relatively large contribution of the direct precipitation falling into the lake compared with the contribution drainaged by the urbanized areas,the low capacity of the urban drainage networks and the urban channel＇s small slope and capacity to pass flood water.