The flood event duration tool

2D models can be configured to produce a variety of useful outputs. However, currently one potentially useful omission from these options is a data output that relays information relating to event duration. A clear way to display event duration data is as a grid where the vertical scale, i.e. colour scale, represents total time when a threshold water level was exceeded.

Although these data are not available from TUFLOW or Flood Modeller, it is a relatively simple post-processing operation to produce it. Therefore, Flood Modeller provides an option to calculate event duration grids from any 2D model result grid.

The raw output data required to produce an event duration grid is simply the flood depths through the duration of the model run (or a user specified sub-period of this). These data can be taken directly from a water depth 2D model output or calculated from the combination of water level 2D model output and an underlying ground grid. The tool utilised the ground grid contained within the 2D results file, hence there is no need to specify a separate DTM for the analysis.

How to use the flood event duration tool