Urban areas in Taiwan are developing rapidly, which results in the creation of impermeable areas that are susceptible to flooding during periods of major rainfall. The strategy of flooding control in urban areas must take a multivariate approach to adapt to changing climates. Low impact development (LID) is a recent and popular approach used in lfooding control. It uses a smal part of an area to inifltrate storm water into local aquifers by using multi-units to spread the storm water runoff and restore the local hydrologic cycle. Taichung City is composed of several thick gravel deposits underneath a thin layer of top soil about one meter thick. The LID concept was applied by building a bio-retention pond next to a building, which received storm water collected on rooftops while allowing the water to inifltrate the aquifer. The ifrst experiment was conducted in a rain garden next to a university campus building. It was found that the increase of aquifer inifltration was proportional to the circular area. This area refers to the contact area between gravel piles and the soil of top layer. The artiifcial recharge was determined by col ecting the inifltration rate of the bio-retention pond before and after the instal ation of the gravel pile. The data show that the bio-retention pond original saturate inifltration rate is 24.7 cm/hr. After the addition of the gravel pile, the inifltration rate is increased to 477 cm/hr. An inifltration pipe was also instal ed in a parking lot, which increased the inifltration rate through the permeable pavement 18~35 times higher than the original rate. In order to simulate the effect of instal ed inifltration pipe, a storm water management model (SWMM) is used to determine the amount of required inifltration pipe and the reduction percentage of the total runoff. The best conifguration is achieved by altering interlock brick to grass brick while instal ing inifltration pipe. In this scenario, a reduction of 15%of the surface runoff volume is possible during a 5-year rainfal period..%海峡两岸之都会地区快速发展，使不透水地表面积增加，加上降雨型态逐渐改变，都市防洪必须采取更多元的策与手段，以因应此一趋势所造成的挑战。近年来，国际间常采用低冲击开发（low impact development, LID）之入渗工法为都市防洪的手段。低冲击开发措施，是利用开发区域其中一小部分土地，以小单元分布式之入渗方式削减地表径流，恢复该区块之原始水文循环状态，以提升地下水补注、降低热岛效应，以实现海绵城市之概念。本研究以台中市卵砾石地层为研究对象，导入上述低冲击开发概念，以办公大楼旁之空地，设置一植生滞留池并加入砾石桩，利用砾石桩之高渗透性，将自大楼屋顶收集之降雨径流，快速导入含水层中，进而补注地下水。人为注水试验结果显示，植生滞留池于设置砾石桩后，入渗率可提升约10倍，而自然降雨事件入渗率效果更加显著。以暴雨径流管理模式（storm water management model, SWMM）评估植生滞留池设置前后之功效，植生滞留池设置后，于5年重现期距降雨事件下，可达到86%出流体积削减，也降低5%洪峰流量，设置砾石桩后，于自然降雨事件中植生滞留池皆未产生地表出流。而以停车场铺面区域为例，加入垂直式渗透导管改造后之透水铺面饱和入渗率计算值可增加18~35倍，模拟子集水区与铺面改造情境下加入垂直式渗透导管，考虑设置数量与削减径流百分比，其设置面积10%时发挥最佳削减效益，以连锁砖改造为植草砖之情况设置垂直式渗透导管面积达10%与现况情境相较之下，于五年重现期降雨可削减15%以上之地表径流体积。
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