A Water Quality rule can be applied at site or at a downstream location. To create a Water Quality Rule, right-click on a Zone in the Operation Tree on the Reservoir Editor's Operations tab and select Add New Rule… Figure 12.8 – Add New Water Quality Rule
The New Operating Rule dialog will appear.
Figure 12.9 – Water Quality Operating Rule
Enter a name for the rule in the Rule Name field. Water Quality Rules can be applied to any opening on the Reservoir by selecting one of the options in the Operates Release From dropdown list. In the Downstream Location dropdown, select Water Quality Rule for the Rule Type and select where the rule will apply. Click OK, and the rule will appear in the Zone Tree.
Figure 12.10 – Water Quality Rule
The Water Quality Rule settings resemble those of the Downstream Option Rule. The user sets the Function through the Define… button, which launches the standard Independent Variable Definition dialog.
Figure 12.11 – Water Quality Rule- Independent Variable Definition
The Limit Type will be Minimum and Maximum. The Interp. dropdown will contain Linear, Cubic, and Step. The Downstream Location will display the Downstream Location selected when the rule was created. The constituent for which the rule is operating can be selected from the Constituent dropdown list, which contains all the constituents from the selected Constituent set.
Enter the Constituent values in the table, depending on the Function selection.
The Use Flow Augmentation option checkbox allows users to turn on the use of additional flows to meet the Downstream requirements. Flow augmentation will only be used if existing releases cannot be re-allocated to meet the Water Quality objective. This option is defined through the Use Flow Augmentation dialog, which is accessed through the Edit button.
Figure 12.12 – Use Flow Augmentation
The Maximum Flow Augmentation sets the total amount of flow allowed to be used to meet the Water Quality objective. The Maximum Yearly Volume sets the maximum volume of water to be released for flow augmentation for the Water Quality Rule per year.
The Evaluation Period… button brings up the Evaluation Period dialog. Through this dialog, the user can set whether the constituent is evaluated instantaneously at each time step (which is the default setting for this property), or if the constituent value is evaluated over a period of time. Users can select either Minimum, Maximum, or Average in the dropdown, and then set the number of days to evaluate that selected statistics in the For Period of field.
Figure 12.13 – Evaluated Period
The Water Quality Rule will include the standard set of right-click options that apply to other rules in the Zone tree.
Figure 12.14 – Water Quality Rule- Right Click Option
Right-click menu options will also be available in the Rule menu option.
Figure 12.15 – Water Quality Rule- Menu Option
