An HEC-WAT compute requires an HEC-WAT alternative, an analysis period, a program order, and model alternatives.
To create an analysis period:
From the HEC-WAT main window, from the Study Tree, right-click on the Analysis Periods folder. From the shortcut menu click New.
The Create New Analysis Periods dialog opens. In the Name box enter a name (FRA_TW). In the Time Window box enter the information required for the time window. The FRA Analysis Period must have a start date and end date that encompass a whole number of years, and the number of years in the time window determines the number events that will be simulated in the FRA compute. Typical Flood Risk Analysis simulations will only model shorter time windows within each year as part of the flood event, however large complex watershed systems may require using the full year available to each compute. The state date should be set such that it is prior to the typical flood season, such as using the first of October to simulate events within water years.
For the Start Date and End Date, enter in the format ddmmmyyyy. The Start Time and End Time should be entered as military time - e.g. 0000, 0600, 1300 (1 p.m.), 2400 (midnight).
Click OK to close the Create New Analysis Periods dialog and create the analysis period. The HEC-WAT main window, will show the new analysis period name in the Study Pane, under the Analysis Periods folder.
