Stormwater hydrographs simulated for different structures of urban drainage network: dendritic and looped sewer networks

Abstract

ABSTRACT Despite urban drainage pipe networks being of great significance to urban flood control, few studies have focused on the influence of urban drainage pipe network structure on hydrological response. We studied two areas in downtown Dongying, Shandong Province, China, which have dendritic and loop drainage pipe networks, respectively. The loop network was converted to a dendritic system for scenario analysis using numerical simulation. Comparing the hydrological response of the original drainage system and the converted system showed that although the dendritic network could reduce node flood volume, the dendritic pipe overload situation was inferior to the loop network. Runoff in the former network was predominantly concentrated in the main pipes and near the outlets and the discharge-peak at the outlet was 47.0% greater than that of the loop. Thus, the loop drainage pipe network is more likely to reduce peak runoff at the outlet, which helps decrease flood risk.