Contents 1 Executive Summary ....................................................................................................... 1 2 Introduction .................................................................................................................... 6 2.1 Purpose of the Flood Modelling Guidance ............................................................. 6 2.2 How to use this guidance ....................................................................................... 8 2.3 SEPA input into modelling studies .........................................................................
9 3 Scoping ........................................................................................................................ 10 3.1 Introduction .......................................................................................................... 10 3.2 Define Modelling Objective .................................................................................. 10 3.3 Developing a Conceptual Model .......................................................................... 10 3.4 Spatial Extent ......................................................................................................
12 3.5 Joint Studies ........................................................................................................ 14 3.6 Level of Assessment............................................................................................ 17 3.7 Modelling Approach ............................................................................................. 17 3.7.1 Selection of Modelling Software ..................................................................... 20 4 Commissioning a study ................................................................................................
22 4.1 Introduction .......................................................................................................... 22 4.2 Statement of Requirements (SoR) ....................................................................... 22 4.3 Quality Control ..................................................................................................... 22 4.4 Resources ........................................................................................................... 22 4.5 Timescale/Milestones ..........................................................................................
23 4.6 Risk Register ....................................................................................................... 23 4.7 Meetings and Progress Reports .......................................................................... 23 4.8 Intellectual Property Rights .................................................................................. 23 5 Data ............................................................................................................................. 24 5.1 Introduction ..........................................................................................................
24 5.2 General Considerations ....................................................................................... 24 5.3 Data collection ..................................................................................................... 24 5.3.1 Data registers ................................................................................................ 24 5.3.2 Licensing ....................................................................................................... 25 5.4 Historic Flooding Information ...............................................................................
25 5.4.1 Use of data .................................................................................................... 25 5.4.2 Available Datasets ......................................................................................... 25 5.5 Topographic and Bathymetric Data ...................................................................... 27 5.5.1 Reuse of existing data ................................................................................... 27 5.5.2 Commissioning a New Survey ....................................................................... 28 5.5.3 Data Format ...................................................................................................
28 5.5.4 Channel Survey ............................................................................................. 28 5.5.4.1 Commissioning a New Channel Survey ................................................... 28 5.5.4.2 Cross-Sections ......................................................................................... 29 5.5.4.3 Hydraulic Structures ................................................................................. 30 5.5.4.4 Flood Defence Survey .............................................................................. 30 5.5.5 Digital Elevation Models (DEMs) ....................................................................
34 5.5.5.1 Existing Data Sets .................................................................................... 34 5.5.5.2 New Data Collection ................................................................................. 35 5.5.6 Bathymetric Data ........................................................................................... 38 5.5.6.1 Commissioning New Bathymetric Surveys ............................................... 38 5.5.6.2 Coastal Defence Survey .......................................................................... 38 5.6 Operating Information ..........................................................................................
38 5.7 Existing Studies ................................................................................................... 39 5.8 Hydrometric Data ................................................................................................. 40 5.8.1 River Levels and Flows .................................................................................. 40 5.8.2 Rainfall Data .................................................................................................. 42 5.8.3 Soil Moisture and Evaporation Data ............................................................... 43 Flood Modelling Guidance for Responsible Authorities v1.1 2