城市化对南明河水系的洪水影响

Influence of Urbanization on Flood in Nanming River Water System

针对贵阳市城市化引起的城市防洪严峻的问题,基于1980~2015年贵阳市水文站的观测资料、南明河水系分布图和贵阳市溶洞、暗河实测资料,利用调洪演算法定量计算了贵阳市城市化前后的年最大流量与汇流历时,研究了城市化对南明河水系的洪水影响。结果表明,经城市化后汇流历时缩减10.07%~23.31%,相应的年最大流量增加15.86%~24.67%,典型洪水年年最大流量增幅与历时减幅明显高于非洪水年,暗河与溶洞在贵阳市城市化的进程中对南明河水系的洪水起到了削峰滞洪的作用,所以合理利用暗河与溶洞,削弱城市化对南明河水系的洪水影响迫在眉睫。

Urbanization caused serious problems for urban flood control in Guiyang City.Based on observational data of hydrological station in Guiyang City,water system distribution map of Nanming river,underground river and Karst caves,and underground river measured data from 1980 to 2015,annual maximum flow and concentration time before and after urbanization of Guiyang were calculated by using flood routing method.And then the impacts of urbanization on water system of Nanming river were studied.The results show that the concentration time shortens 10.07%-23.31% after the urbanization,the corresponding annual maximum discharge increases 15.86%-24.67%,annual maximum flow rate and duration reduction of a typical flood year are significantly higher than that of year without flood,underground rivers and Karst caves plays a role of flood detention in Nanming river water system after urbanization.Therefore,rational use of underground rivers and caves and weakening the effect of urbanization on the flood of Nanming river system is imminent.