The Flood Estimation Handbook (FEH) rainfall model is a method of modelling rainfall data for drainage simulation and flood analysis.
The FEH 1999 model estimates rainfall using a rainfall depth-duration-frequency model.
The DDF model is defined by six parameters (c, d1, d2, d3, e, f) which you can input by clicking on the "FEH99" button in the Auto Size and Level Network window or the Storm Simulation window.
The FEH 2013 dataset also uses a depth-duration-frequency model similar to the FEH 1999 model but with improvements based on modern data analysis. FEH 2022 is a further improvement on that with increased temporal resolution and coverage. These datasets are typically given as an XML file.
The FEH22 file format remains the same as the FEH13, in fact both sets of data may be in the same file. Site3D can load files which contains both FEH13 and FEH22 datasets as well as files which only have either FEH13 or FEH22 data. In the situation where a file has both FEH13 and FEH22 data, Site3D will prefer the FEH22 data where possible.
The rainfall data is represented as a matrix of depths for standard return periods and durations. You can load a FEH13 or FEH22 dataset from a file by clicking on the "FEH13 or FEH22" button in the Auto Size and Level Network window or the Storm Simulation window.
Press the Browse button to select the file on your computer, or you can manually type or paste the file path directly into the input box.
