Welcome to the HEC-FDA Version 2.0 Quick Start Guide. This document is written for users who have previous experience using the HEC-FDA software or have experience working with hydrologic, hydraulic, and economic data. Please first review Differences between Version 1.4.3 and Version 2.0 and How-to Setup a Successful Compute. The example study data used throughout this Quick Start Guide can be reviewed and downloaded here: Example Study Data.  Review the HEC-FDA User Manual for more information.

2.0 Data Requirements for a New HEC-FDA Study

Study data requirements vary widely. The requirements depend on the purpose of the study, the size of the study area, the hydrologic and hydraulic conditions of the study area, and the types of alternative plans considered, just to name a few. In general, the data required to build a new study must contain:

1. Impact areas in the form of a polygon shapefile. The file must have a string or integer field that identifies a unique name. Only one set of impact areas can be imported.  
2. Analysis year(s).

Further, for a given alternative, analysis year, and impact area, a study must contain at a minimum the following data:

1. Frequency functions - either (a) or (b) below: 
   1. Analytical flow-frequency: equivalent record length, mean, standard deviation, and skew. 
   2. Graphical frequency relationship: at least 8 (preferably 9) flow-frequency coordinates and equivalent record length. Stage-frequency is an option of the hydraulic conditions warrant.
2. Stage-discharge functions consisting of flows and distributions of stages, if frequency function reflects discharge. If frequency function reflects stage, a stage-discharge function is not required.
3. Aggregated stage-damage functions consisting of stages and distributions of damage, which can be manually entered or internally computed. 

If you're using HEC-FDA 2.0 to compute the aggregated stage-damage functions, you will also need:

1. Terrain, for one or both of the following: (1) using HDF results for hydraulics, in which case the terrain should be in HDF format, or (2) using terrain data for ground elevation at structure, in which case the terrain can be imported as a raster data set or HDF. Only one terrain file can be imported.  
2. Hydraulics data set should reflect water surface elevations (not depth) with three data format options: (1) steady or unsteady: 8 subdirectories with raster datasets (2) steady: 1 HDF; or (3) unsteady: 8 HDFs.
3. Discharge-frequency function and stage-discharge function, or stage-frequency function only (same functions mentioned above). 
4. Occupancy types with damage categories, depth-percent damage functions with uncertainty, first floor elevation uncertainty, and either: (1) structure/content/other value uncertainty, or (2) content-to-structure value ratios with uncertainty and other-to-structure value ratios with uncertainty. Content, vehicle, and other configuration is optional. 
5. Structure inventory in the form of a point shapefile with at least a structure ID, structure value, first floor elevation (or ground elevation and foundation height) and occupancy type. Optionally: content value, other value, beginning damage depth, among others. 

Stage-Damage H&H Data

• There are three types of engineering data required for a stage-damage compute: a frequency function, a stage-discharge function if frequency reflects flows, and a hydraulics data set. Double-check that the project conditions are the same across the three items. The computed stage-damage function will not make sense if: (1) with-project conditions are unique from without-project conditions, and (2) with-project data is used along with without-project data for the without-project set of stage damage functions. 
• Ensure that the coordinate reference system is either set to be the same across all geospatial data sets, or that the study coordinate reference system is set by selecting the study projection from the study properties editor under the File menu. 

Optional items include:

1. Index points in the form of a point shapefile, if retrieving graphical stage-frequency from water surface elevations in hydraulics. Index points are not explicitly used for anything else within HEC-FDA, but remain an important concept. 
2. Regulated-unregulated transform function with unregulated flows and distribution of regulated flows.
3. Exterior-interior function with exterior stages and distributions of interior stages. 
4. Levee (top of levee elevation) and optionally system response curve involving stages and distributions of breach probabilities.

Here's what you'll need from engineering

1. For each alternative-analysis year-impact area combination, you will need from engineering:
   1. Frequency functions - either (a) or (b) below: 
   2. Analytical flow-frequency: (1) equivalent record length, mean, standard deviation, and skew, or (2) series of peak flows. 
   3. Graphical frequency relationship: at least 8 (preferably 9) flow-frequency coordinates and equivalent record length. Stage-frequency is an option of the hydraulic conditions warrant.
   4. Stage-discharge functions consisting of flows and distributions of stages, if frequency function reflects discharge. If frequency function reflects stage, a stage-discharge function is not required. 
   5. The frequency function and stage-discharge function should reflect the same place in the channel, i.e. the same index point.
2. You will also need a data set of hydraulic modeling for each alternative-analysis year combination. The modeling should reflect water surface elevations (not depth) with three data format options: (1) steady or unsteady: 8 subdirectories with raster datasets (2) steady: 1 HDF; or (3) unsteady: 8 HDFs
3. You will need the .prj file used in the HEC-RAS modeling to set the HEC-FDA study projection

Create New Study and Compute Workflow

The pages included below walks you through creating a new study and computing all results. Start with Part A and work through the workflow through Part D. These pages are written with the assumption that you will use HEC-FDA Version 2.0 to compute aggregated stage-damage functions. Steps on optional functionality that will not be used for all studies, i.e., steps that are not required, will be indicated as optional. From the HEC-FDA Version 2.0 software, right-click on each item in the study tree to import or create new study data. 

Duplicates Not Needed

1. If a given study data item is the same for multiple project conditions, then that study data item need not be duplicated. For example, assume that you have a flow-frequency function for the existing condition of a given impact area, but the flow-frequency function is also representative of the hydrologic conditions of the future-without project condition, and all with-project conditions. In that case, create one frequency function, and select the same frequency function for each of the Scenarios. 
2. Except for terrain and the set of impact areas, many items can be created for a given study data element. For example, multiple structure inventories can be imported. 

Related Topics

Review the HEC-FDA User Manual's Create New Study from Scratch page for additional information for creating a new study from scratch.