WMS:HEC-1 Parameters

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Attributes or parameters for all HEC-1 hydrograph stations are defined and/or later edited using the Edit HEC-1 Parameters dialog. This dialog is accessed by selecting the Edit HEC-1 Parameters command from the HEC-1 menu or by double-clicking on basin, outlet, or diversion icon from the Graphics Window.

If a basin, outlet, or diversion is selected before issuing the command then data for that object appears in the text window at the bottom of the dialog. The top portion of the dialog lists the HEC-1 cards that can be edited by selecting the corresponding button. When a hydrograph station is selected (basins/outlets/diversions) only the buttons that edit parameters associated with that hydrograph station are active, all others are dimmed. In addition to using the appropriate button, HEC-1 attributes can be edited by clicking on the HEC-1 card in the text display window. Using this method, job control parameters can be edited by first toggling their display using the Display Job Control Cards toggle box, and then selecting a job control card from the text display window.

Once the dialog appears it becomes part of the main screen until you select the Done button. Therefore, you can continue to select additional, or other hydrograph stations so that data for that object may be edited without exiting the dialog. You can use the previous and next hydrograph station buttons to cycle through hydrograph stations in the order they are computed by HEC-1. Since the dialog is part of the main screen, all menu commands are active while this dialog is present.

Diversion HEC-1 Cards

Diversion Data...

HEC-1 allows flow to be diverted from an outlet or drainage basin. This flow can be thought of as leaving the normal drainage system at that point. It can be retrieved at a downstream outlet where the diverted flow then contributes to the flow at that outlet. If no downstream retrieval outlet point is specified, the flow simply leaves the system at the diverted outlet point and never returns.

Editing Diversion Data (DT)

Diversions are created using a combination of the Add | Diversion and Retrieve Diversion commands found in the Tree menu. Once created, data for the diversion can be defined and/or edited by selecting the Diversion Data button from the Edit HEC-1 Parameters dialog.

The following data should be defined for a diversion:

• Name – The name identification string of the diversion as used on the DT record. It is important to assign a unique name to each diversion in a given model because this name is used by WMS and by HEC-1 to identify the diversion.
• Max Volume – Maximum volume of diverted flow in acre-feet (1000 cu m).
• Peak Flow – Peak flow that can be diverted in any computation period in cfs (cms).
• Outflow name – Name used on KK record where flow is diverted.
• Inflow name – Name used on KK record where flow is retrieved.
• The flow capacity of a stream flow diversion is specified using an inflow (DI) and outflow (DQ) tables. These tables are defined with the XY Series Editor by clicking on their respective define buttons.

Related Topics

• Job Control Data
• Basin Data
• Loss Method
• Unit Hydrograph Method
• Precipitation
• Snowmelt
• Routing
• Reservoirs
• Diversions
• Output Control
• Model Check
• Running an HEC-1 Analysis