Assessing Flood Indirect Impacts on Road Transport Networks Applying Mesoscopic Traffic Modelling: The Case Study of Santarém, Portugal

Abstract

The key aspect for the quantification of indirect impacts of flooding is the assessment of the disruption of the transportation service considering social and economic consequences. To investigate how flooding can affect road transportation, it is essential to analyze interaction during the flood event itself, as well as on the following days. In this work, two static and dynamic traffic models are applied to a study zone for quantification of the performance and functionality of the network during the flood and after the failure of infrastructure components. A mesoscopic simulation was applied to identify the traffic disruption in the face of flood events. This simulation is capable of considering the road network model, assigning trip paths with the impact of road closures and speed reductions, and evaluating travel time and vehicle volume redistribution in a given disruption scenario. By comparing the traffic analysis results (travel time, travelled distance and street speed changes) in normal and flooded situations, the impact of flooding on a transportation network could be examined. Moreover, modelling outputs from a case study in the Santarém region (Portugal) indicated that in analyzing the flood impacts on a traffic network, even non-flooded infrastructures must be taken into account because of their service disruption.

Edge-based graph neural network for ranking critical road segments in a network

“…Here, ⋅ denotes the nearest integer function. While the 1% edge deletion number is arbitrarily assumed for the ablation study, this is not far from reports from previous events such as from a 20-year return period event resulting in 0.6%-0.7% loss in the road inventory [ 86 ].…”

A new approach to determine the flood hazard impact on road network using 3D city model

“…References [37] and [38] recommended 30 cm as the ultimate threshold at which a passenger vehicles starts to float. Reference [39] sugested close the road if the water depth exceeds 30 cm. Accordinglly, the flood water depth in the study was classified into four classes.…”

A Systematic Literature Review of the Hybrid Methodologies in Assessing Flood Indirect Impacts on Transportation

“…Temporal and Spatial Scales Up to 2020 30 Johnston et al [13] A review of floodwater impacts on the stability of transportation embankments Not determined Not determined Nazarnia et al [9] reviewed studies on the direct impacts of sea level rise, a specific flood type in coastal regions, on different types of urban infrastructures' resilience, including transportation, water, and energy. Similarly, Ahmed and Dey [11] reviewed articles on both man-made and natural disasters' direct impacts on transportation systems' resilience.…”

“…Of the articles modeling Europe, Balijepalli and Oppong [19], Green et al [3], Pregnolato et al [20], and Coles et al [21] focused their models on the UK; Pérez-Morales et al [22], Martín et al [23], and Pyatkova et al [24] on Spain; Borowska-Stefa ńska et al [25] and Borowska-Stefa ńska et al [26] on Poland; Arrighi et al [27,28] on Italy; Mitsakis et al [29] on Greece; and Shahdani et al [30] on Portugal. The distribution of articles across Europe highlights the high and frequent levels of disruption in traffic caused by flooding.…”

“…This approach is commonly used for the static integration of flood and traffic models. Several studies, including those by Han et al [40], Shahdani et al [30], Zhang and Alipour [41], Sohn [34], and Martín et al [23], have employed this methodology.…”