中文摘要：

快速城市化所引发的产汇流改变,使城市区域洪涝灾害进一步加剧。针对北京凉水河流域内城市化所引起的不透水面积增加、河网结构形态改变、城市分洪和排水管网铺设等人类活动,选取流域内大红门排水区为研究对象,根据遥感影像和实地调研,分别构建城市开发前、后两种情景的暴雨洪水管理模型（SWMM）,并采用流域出口断面实测流量率定模型参数。通过设置不同重现期暴雨情景,定量分析城市开发前后洪水特征的变化。研究结果表明：SWMM模型在城市开发前后两种情景都具有较好的适用性。城市化后大红门排水区地表径流量是城市化前约3.5倍,径流系数从城市化前的0.12提高到城市化后的0.41,下渗量是城市化前的2/3;城市化后排水区坡面汇流速度加快,河道汇流时间降低,峰现时间无明显变化。城市化前百年一遇24 h洪峰流量低于城市化后20年一遇洪峰流量。本文的研究成果可为流域尺度雨洪综合管理和低影响开发提供技术支撑。

英文摘要：

Rapid urbanization has an adverse impact on urban rainfall-runoff processes and may increase the flood risk of urban regions. This study considered intensive human activities, such as increases in impervious area, changes in river network morphology, drainage system laying, and water transfer. We have developed two storm water management models（SWMM） based on remote sensing image and field survey, considering different urbanized scenarios and human disturbances and using measured streamflow data for model calibration and validation. Precipitation with different return periods was taken as model input to analyze the changes in flood characteristics caused by urbanization. The results indicate that these two models can produce good estimation of storms under the scenarios examined. The surface runoff after urbanization was 3.5 times larger than that before urbanization; the coefficient of runoff jumped from 0.12 to 0.41 and the amount of infiltration decreased from 88% to 59%. After urbanization, the time for overland flow concentration was shortened while the time for river concentration became longer; the flood peak time did not indicate much difference in this study. The peak flow of 20-year return period after urbanization is larger than that of 100-year return-period before urbanization. The results in this study would provide technical support to planning and management of urban storm water and evaluation on the low impact development technology.