Formulation of a fast 2D urban pluvial flood model using a cellular automata approach

Abstract

With the increase in frequency and severity of flash flood events in major cities around the world, the infrastructure and people living in those urban areas are exposed continuously to high risk levels of pluvial flooding. The situation is likely to be exacerbated by the potential impact of future climate change. A fast flood model could be very useful for flood risk analysis. One-dimensional (1D) models provide limited information about the flow dynamics whereas two-dimensional (2D) models require substantial computational time and cost, a factor that limits their use. This paper presents an alternative approach using cellular automata (CA) for 2D modelling. The model uses regular grid cells as a discrete space for the CA setup and applies generic rules to local neighbourhood cells to simulate the spatio-temporal evolution of pluvial flooding. The proposed CA model is applied to a hypothetical terrain and a real urban area. The synchronous state updating rule and inherent nature of the proposed model contributes to a great reduction in computational time. The results are compared with a hydraulic model and good agreement is found between the two models.

An Advanced Method to Apply Multiple Rainfall Thresholds for Urban Flood Warnings

“…In England and Wales, the Environment Agency classifies flood warning into three levels, i.e., Flood Alert, Flood Warning, and Severe Flood Warning increased by severity [25]. Theoretically, this gradation of warning levels can be accomplished by flood simulations in space and time through the incorporation of meteorological and hydrological models, which, again, is very time-consuming that requires simplification or modification to meet the need for real-time operation [26][27][28][29]. To increase the lead time, attempts have been made by many researchers to incorporate precipitation forecast products into hydrological warning systems, in which ensemble techniques are necessary to address the uncertainties in hydro-meteorological forecasting [30,31].…”

An integrated framework for high-resolution urban flood modelling considering multiple information sources and urban features

“…CADDIES is a fast 2D urban flood simulation model based on the principle of cellular automata (CA) (Ghimire et al, 2013;Gibson et al, 2016;Guidolin et al, 2016;Guidolin et al, 2012). This model's effectiveness has been proven on the EA's 2D benchmark test cases and real world case studies (Guidolin et al, 2016).…”

“…Significant efforts have been made during the last few decades to improve accuracy and efficiency of urban flood modelling through enhanced methodology and numerical methods (Bates et al, 2010;Chen et al, 2007;Chen et al, 2010;Nguyen et al, 2006) and applications of parallel computing technologies (Ghimire et al, 2013;Glenis et al, 2013;Lamb et al, 2009;Smith and Liang, 2013). However, modelling accuracy is still affected by four main issues: 1) the level of details available in the topographic representations of terrain and urban key features (Haile and Rientjes, 2005;Horritt and Bates, 2001;Leandro et al, 2016;Rafieeinasab et al, 2015); 2) the lack of calibration and validation data (Fu et al, 2011;Hall et al, 2005;Horritt, 2000;Leandro et al, 2011); 3) the approach used to consider the effects of underground urban drainage infrastructure (drainage capacity) Environment Agency, 2013b); and 4) the uncertainty of accelerated land use changes (De MOEL and Aerts, 2011;Du et al, 2015;Shi et al, 2007).…”

An Adaptive Relaxed Cellular Automata Method for Reliability-Based Hydropower Operation of Reservoirs

“…They used an unstructured CA in the vegetation module. Ghimire et al [39] used two-dimensional CA for ood modeling. Austin et al [40] presented an e cient and accurate conceptual CA-based simulator for sewer networks simulation.…”