Comparison of runoff from low-impact development measures in arid and humid cities

A study was undertaken to identify differences in the performance of low-impact development (LID) measures in arid and humid cities. Yinchuan and Guangzhou in China were selected as a representative of each type. A stormwater management model was constructed with the aid of a geographic information system and LID measures of permeable pavements (PP), rain gardens (RG), green roofs (GR) and combinations of these were then designed. The results showed that a combination of PP, RG and GR provided the largest reduction in total runoff, peak runoff and runoff coefficient in both cities. Paired measures also delivered a significantly higher performance than single measures, with PP plus GR better than other paired combinations. The results of this work could guide the construction of sponge cities in both arid and humid areas.