Logic Overview, Configuration and Transition Guidance

The Environmental Flow Node (EFN) is required to manage environmental flows. Where water used for the environment needs to be accounted for, EFNs are used in conjunction with an Environmental Flow Manager and Resource Assessment System.

From version 5.51 onwards, the Spell Observer logic will be the default mechanism for determining if the spell-based environmental flow has been successfully met. This will feed into the logic around ordering at Environmental Flow Nodes. For compatibility with models that used the Environmental Flow Node logic before version 5.51, this ‘old’ logic will be temporarily available via Application Settings > Experimental/Redundant Features. In the future, this ‘old’ logic is expected to be removed from Source.

New Environmental Flow Node Logic (Default)

The Environmental Flow Node Logic, introduced in version 5.51, improves how successful events are measured at Environmental Flow Nodes by splitting the observation of events from the ordering of events. This logic will be the standard approach across all new and compatible projects.

In addition to the logic changes, the EFN interface has been updated, removing redundant elements. Defaults have also been adjusted so the "Duration Below End Target" is set to 1 for new actions, and the "Minimum Interval Between Ordered Spells" field is automatically disabled when the "Number of Spells in Season" is set to 1, minimizing the need for manual adjustments.

To ensure the New Environmental Flow Node Logic is active, open Source and navigate to Edit > Application Settings. Under the Experimental/Redundant Features section, confirm that the Enable Old Environmental Flow Node Logic checkbox is unchecked, as shown in Figure 1. Save the settings and restart the application if prompted.

For existing projects with only partial or no configuration of the Spell Observer at spell-based actions, the system will automatically enable the old logic (and interface) and log a warning to notify the user.

For existing projects where all spell-based actions have the Spell Observer configured, the model will be able to be opened with the new interface once the user unchecks the Enable Old Environmental Flow Node Logic in the application settings.

Open

User Guide for New Environmental Flow Node Logic (Default) is available here.

Old Environmental Flow Node Logic (Legacy)

The EFN logic and interface from version 5.50 have been temporarily retained to ensure compatibility with older projects. However, they are considered redundant and are scheduled for removal in future updates. eWater encourages all users to transition to the new EFN logic and to avoid setting up new models with the old logic.

However, should you need to enable the Old Environmental Flow Node Logic, navigate to Edit > Application Settings and check the Enable Old Environmental Flow Node Logic box in the Experimental/Redundant Features section. Save your settings and restart the application to apply the changes.

The User Guide for Old Environmental Flow Node Logic can be found here.

Transition Recommendations

It is recommended that the New EFN logic be used by default for all new projects. This logic offers enhanced functionality, a simplified interface, and optimized default settings.

Users are encouraged to transition to the New EFN logic for existing projects. This ensures long-term compatibility with future updates and allows users to benefit from the streamlined workflows and improved interface. The Old EFN logic should only be used for projects that require legacy compatibility, those created in version 5.50 or earlier and reliant on specific features no longer supported in the new logic.

Adopting the New EFN logic ensures alignment with future releases and provides a more efficient and user-friendly modelling experience.