根据雨水的循环过程设计开阔的地面。一般说来,铺装的地面其地表径流大;而开阔的地面,其地表径流小:开阔的地面可以吸收大部分的雨水,同时也可以通过一些植物或地被等吸收和蒸发部分雨水,而剩下的一小部分则以地表径流的形式排出(图二)。另外一个设计是将下水管道的直径减小,这样一来水流量会大大降低,而积水的径流速度也会减小,同时也可以更好的节约经济成本。 According to the rain cycle design open ground. In general, paved ground surface runoff large; and open ground, the surface runoff is small: open ground can absorb most of the rain, but also by some plants or ground by the absorption and evaporation of part of the rain, and The remaining small part is discharged as surface runoff (Figure 2). Another design is to reduce the diameter of the sewer pipe, so that water flow will be greatly reduced, while the stagnant water runoff rate will be reduced, but also can better save economic costs.