A hybrid method for evaluating the resilience of urban road traffic network under flood disaster: An example of Nanjing, China.

Urban road traffic network (URTN) plays an important role in city operation, while it is also suffered a lot from the urban flood disasters which caused negative impacts frequently, like traffic congestion, and road collapse. The function loss of URTN not only destroy normal urban life and work order, but also pose a serious threat to people's lives and properties. Therefore, it is urgent to quantitatively explore the flood resilience of URTN. The concept of resilience puts forward new ideas to help solve the problem of urban flooding disasters from a holistic view. Exploring the flood resilience of urban traffic network may help to mitigate urban flooding and improve the urban resilience. This paper developed a flood resilience evaluation model of URTN, which contains 26 indicators based on the 4R theory. A case study was conducted in southern China to validate the model with real data. It evaluated the urban flood resilience of road traffic network with a comparison of before and after reconstruction of the pipeline. The results demonstrated that the flood resilience of URTN is at a relatively low level in the study area, and the limitation of single traditional engineering measure to the flood resilience of URTN. Suggestions such as strengthening the citizen participation and enhancing the complementary capability of multiple engineering measures are proposed to further promote the flood resilience of the URTN.

Li D ，Zhu X ，Huang G ，Feng H ，Zhu S ，Li X ... -  《-》

Urban flooding resilience evaluation with coupled rainfall and flooding models: a small area in Kunming City, China as an example.

Xu T ，Xie Z ，Jiang F ，Yang S ，Deng Z ，Zhao L ，Wen G ，Du Q ... -  《WATER SCIENCE AND TECHNOLOGY》

A study on dynamic simulation and improvement strategies of flood resilience for urban road system.

As one of the most important and directly affected infrastructure by flood disasters in urban areas, the road system plays a crucial role in maintaining the order of human production and life, as well as providing a foundation for the implementation of emergency response work in disaster scenarios. The existing flood resilience quantification methods based on maximum inundation depths of each individual road unit neglects the influences on flood resilience caused by the connectivity of road system. Therefore, this paper focuses on the road system, simulates the flood resilience of the road system in multiple disaster scenarios based on the functionality curve of road system under rainfall-inundation processes, then quantifies the improvement effect of Low Impact Development (LID) measures on flood resilience. A case study is conducted in Yunmen community, Jingdezhen city in China. The results indicate that: (1) The flood resilience of the road system decreases with the increase of rainfall intensity under different scenarios, and the magnitude of the decrease reduces. (2) The road system exhibits strong adaptability during the early stages of rainfall; The duration of functionality loss increases with increasing of rainfall intensity in different scenarios. (3) Implementation of LID measures can significantly improve system robustness by enhancing the reliability of the roads around critical nodes, thereby effectively enhancing flood resilience. The conclusions can provide a theoretical basis for decision-makers to develop urban flood mitigation engineering plans and resilience strategies tailored to local conditions.

Zhang J ，Wang H ，Huang J ，Wang Y ，Liu G ... -  《-》

A research on urban disaster resilience assessment system for rainstorm and flood disasters: A case study of Beijing.

Under the background of global climate change, rainstorm and flood disasters have become the most serious cataclysm. Under the circumstances of an increasingly severe risk situation, it is necessary to enhance urban disaster resilience. Based on the disaster resilience process of prevention, absorption, and enhancement, and considering the safety factors such as personnel, facility, environment and management, this paper forms a dual dimension of the urban disaster resilience assessment model covering the key elements of urban disaster response and the core capacity of urban disaster recovery. Furthermore, if taking into account the characteristics of rainstorm and flood disasters, the paper screens the key indicators to build up an assessment index system of an urban rainstorm and flood disaster. The practical application was implemented in Beijing to have an assessment of the ability to recover from rainstorm and flood disasters in all districts of Beijing. And then, some pertinent suggestions for enhancing the resilience of Beijing to rainstorm and flood disasters were proposed.

Yu S ，Li R ，Zhang Y ，Wang M ，Zhang P ，Wu A ，Yu F ，Zhang X ，Yang L ，Cui Y ... -  《PLoS One》

Flood impacts on urban road connectivity in southern China.

Effective measures to improve road accessibility during storms are required as traffic congestion caused by storm floods increasingly constrains the efficiency of urban commuting. However, flood impacts on urban road connectivity are not yet well assessed due to inaccurate simulation of flood processes in urban areas where high-resolution data for drainage networks and gauged hydrological data are insufficient. Thus, this study assesses flood impacts on road network connectivity in an urban area of southern China through joint modeling of 1-D hydrodynamic processes in drainage networks and 2-D flood inundation processes on roads using MIKE Urban and MIKE 21. High-resolution DEM images of 5 m and a drainage network of 5635 pipelines were used for urban hydrological simulation. Flood depths were gauged for model calibration and validation by recruited volunteers in the context of citizen science. The results show that road network connectivity decreases as rainfall increases. More than 40% of road connectivity is lost in the study area when a 1-in-100-year return period rainfall occurs. The study results can help to inform more adaptive strategies for local flood control. The study methods are also applicable to improving urban hydrological modeling in broader regions.

Zhou R ，Zheng H ，Liu Y ，Xie G ，Wan W ... -  《Scientific Reports》