Validating a rapid assessment framework for screening surface water flood risk

Abstract

Keywords cellular automata flood model; decision support; 2D flood modelling; flood risk management; surface water management plan; urban flooding. Correspondence AbstractThis research evaluates performance of a rapid assessment framework for screening surface water flood risk in urban catchments. Recent advances in modelling have developed fast and computationally efficient cellular automata frameworks which demonstrate promising utility for increasing available evidence to support surface water management, however, questions remain regarding trade-offs between accuracy and speed for practical application. This study evaluates performance of a rapid assessment framework by comparing results with outputs from an industry standard hydrodynamic model using a case study of St Neots in Cambridgeshire, UK. Results from the case study show that the rapid assessment framework is able to identify and prioritise areas of flood risk and outputs flood depths which correlate above 97% with the industry standard approach. In theory, this finding supports a simplified representation of catchments using cellular automata, and in practice presents an opportunity to apply the framework to develop evidence to support detailed modelling.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Comparing cost‐effectiveness of surface water flood management interventions in a UK catchment

“…A full description of this modelling process is available in Ghimire et al (), Guidolin et al (), and the CADDIES website ‐ (Centre for Water Systems, ). Accuracy of the approach is validated in Gibson et al () and Webber, Booth, et al ().…”

“…The surface water intervention assessment framework presented in Webber et al (, b, c) is a four‐stage process that includes: characterising the study area, representing interventions, simulating scenarios, and analysing intervention performance. Flood simulation is undertaken using the CADDIES model.…”

“…Interventions were represented through spatial and temporal manipulation of cell roughness, input, and output parameters (Figure , Webber et al , b, c). Interventions which alter surface roughness are represented in CADDIES via Manning's “n” coefficient to control flow speed across a cell.…”

“…A full description of this modelling process is available in Ghimire et al (2013), Guidolin et al (2016), and the CADDIES website -(Centre for Water Systems, 2017). Accuracy of the approach is validated in Gibson et al (2016) and Webber, Booth, et al (2018). Cellular Automata Dual DraInagE Simulation modelling across a regular grid with parameters describing water input, output, and runoff speed at a cell-by-cell resolution 2.1 | Characterising study area and rainfall…”

Is green infrastructure a viable strategy for managing urban surface water flooding?

“…The viability of green infrastructure to manage urban flooding was tested using the rapid scenario screening framework presented in Webber et al (2018a) and validated in Webber et al (2018b). The framework applies a simplified representation of catchment land use and flood interventions alongside a computationally efficient cellular automata flood model 'CADDIES'.…”