How to troubleshoot system deficiencies in a hydraulic model, like flooding, low pressures, or tank or pipe size

Product(s): WaterGEMS, WaterCAD, SewerGEMS, SewerCAD, StormCAD, CivilStorm, PondPack, HAMMER
Version(s): CONNECT Edition
Area: Modeling


OpenFlows applications have a wide range of use in modeling a water or storm-sewer system. Part of this analysis is to assess if the system can handle the demands or capacity of the system without running into issues, like low pressures or overtopping structures. This wiki will include some of the tools available to help with checking for deficiencies in the system.


Color coding

Element symbology, which includes color coding and annotations, can be a powerful tool to quickly identifying issues in a model. The Element Symbology manager is often docked to the left of the drawing and is also available by going to View > Symbology.


With color coding, you can get a quick overview of the results in a model. For instance, you can use color coding based on pressure results to locate areas of low pressures or find areas where the pipe velocity may be too small or too large. Once you have identified an area with possible issues, you can try to identify why it may be occurring. For instance, you may be able to use this to suggest a new booster pump or as an area to add a larger pipe.

In a storm and sewer model, you can use color coding to identify areas where may be areas where a structure is overtopping or surcharging or if a pipe is reaching a certain capacity.


User Notifications

User notifications are useful messages related to the model. Warning-level and information message can alert you to results like negative pressures at nodes in the model, valves or pumps that are not operating correctly, structures that are surcharging or overtopping, tanks that are empty or full, and much more.

It is possible to zoom to elements mentioned in User Notifications. If you right-click, you have an option to Zoom To. This will highlight the element in the drawing. The Properties grid is docked in the user interface, the properties of the highlighted element. If there are multiple elements with a given notification, there will be an option to selection all elements.


Alerts and Alarms (Water products)

Alerts are custom user notifications that you can create to help see possible areas of concern for the model. For instance, if you want to make sure that no junction in the model has a pressure less than 20 psi or so no pipe velocity is below a certain value, you can generate notifications related on this. Alerts can be set as errors, warnings, or informational messages.

More information on this can be found in this wiki: Creating custom alerts or user notifications.


It is also possible to set tanks with alarms. This will create a user notification if a tank reaches a low or high level. You would set this in the tank properties.

Once this is set “Use High Alarm?” or “Use Low Alarm?” to True, you can enter the elevation or level to use for the alarm. Setting the elevation or level will depend on the operating range type selected for the tank. More information on operating range type can be found here: Understanding Operating Range Type.

Information on tank alerts can be found here:  Using Tank High and Low Alarms.

Engineering Standards (Storm-sewer products)

Engineering Standards are similar to Alerts in the Water products. However, this only applies to the physical or input properties, and they do not apply to computed results.

Engineering standards are used if there are certain input properties or physical properties required by the municipality that you want to have a notification about. These can be errors, warnings, or information messages.


More information on engineering standards can be found here: Using Engineering Standards.


Profiles and Graph

Profiles and graphs are useful to display results, but can also be used as a way to display potential issues in the model.

In a Storm-Sewer model, a profile can be used to visually see the extent of any surcharging or overtopping occurring in a system. Graphs can be used to quickly see how the results change with time.

If there is a potential issue related to controls in a model, graphing the condition and action elements together can be used to identify potential issues with controls, including possible conflicts.


User Data Extensions


While the OpenFlows products include many of the input and results fields required to accurate analyze a system, there may be some cases where a municipality requires data that may not be available. Formula-based User Data Extensions can be useful in cases like this. A formula UDX can be used to create a real numerical field that will be available the element properties or flextables. This field can be based on a formula that uses available input and results fields.

More information on formula-based User Data Extensions can be found here: Creating Formula-Based User Data Extensions.

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