Creating New Rules

When you create a rule, you must:

identify the release element that the rule constrains,
select the rule type, and
give the rule a name (and an optional, but recommended, description).

You learned about release elements in "Physical Properties of Reservoirs". They include the reservoir itself, the dam, the outlet groups, diverted outlets, and the outlets. The only release element to which you cannot assign an operation rule is an uncontrolled outlet because its releases cannot be controlled, and rules are all about controlling releases.

ResSim has several rule types to choose from. The availability of the rule types varies depending on the release element. Some rules can only be applied to a specific type of outlet while other rules can be applied to more than one type of release element. "Table: Matrix of Rule Release and their Available Rule Types" lists the various release elements and the rule types that can be applied to them.

Table: Matrix of Rule Release Element and their Available Rule Types

Rules		Release Elements
Rule Types	Rule Icons	Reservoir	Dam or Group	Controlled Outlet	Power Plant	Pump
Release Function
Downstream Control
Flow Rate of Change
Elevation Rate of Change
Induced Surcharge
Tandem Operation
Hydropower Demand
System Hydropower
Pump Schedule
Scripted
Prescribed Release

Uncontrolled Outlet

Rules cannot be applied to an uncontrolled outlet.

To add a new operation rule to a zone:

Right-click on the zone in the Zone-Rules Tree to which you want to add the new rule.
Select Add New Rule… from the zone's context menu. The New Operating Rule dialog will open ("Figure: New Operating Rule").
Figure: New Operating Rule
The three fields of the New Operating Rule dialog include:
- Rule Name: —Enter a name for the new rule. You may want to enter this after specifying the other two parameters
- Operates Release From:—Select the release element of the reservoir to which you will assign this rule (reservoir pool, dam, outlet group, or outlet)
- Rule Type:—Select the rule type from the selection list. The available rule types in the list will depend upon your selection for Operates Release From.

The new rule will appear, highlighted, at the bottom of the set of rules in the selected zone in the Zone-Rules Tree and the edit panel will display the appropriate rule editor for the new rule's type. The first two fields for each rule editor contain the name of the rule and its description. The description of the rule can be added or changed whenever the rule editor is displayed in the edit panel.