Forebay head loss can be used to model places where there is constriction upstream of the dam, resulting in the forebay being lower then the reservoir "pool." The forebay will determine the outlet capacities while the pool determines the zones. You can add Forebay Head Loss to Dams, Outlets, Diverted Outlets, and Outlet Groups.

To add Forebay Head Loss:

  • Right-click on the dam, outlet, or group to which you want to add Forebay Head Loss.
  • Choose Add Forebay Head Loss from the element's context menu ("Figure: Dam Context Menu - Add Forebay Head Loss").

    Figure: Dam Context Menu - Add Forebay Head Loss


  • The Forebay Head Loss you have added will appear in the reservoir tree as a node beneath the element you selected and the Edit Panel will display the Forebay Head Loss pane ("Figure: Forebay Headloss Node and Forebay Head Loss Edit Pane").

    Figure: Forebay Headloss Node and Forebay Head Loss Edit Pane

Use the Define button to the right of the Function Of: field to specify the independent variable of the Forebay Head Loss function. Options include: Model Variable, External Variable, State Variable, or Two Variables.