Performing a Fireflow Analysis

Any referenced datasets can be downloaded from "Module downloads" in the module overview.

Step-by-step:

A well set up fireflow model can be used to identify hydraulic weaknesses due to proposed operational changes.

  1. Open the appropriate .aprx file in ArcGIS Pro.
  2. From the ribbon, InfoWater Pro tab, Project panel, click Initialize.

To perform the fireflow analysis only on the pipes proposed to be installed by 2030:

  1. In the Model Explorer, expand the Scenario drop-down.
  2. Select the 2030_MAXDAY scenario.
  3. Click OK to confirm.
    The Model Explorer, with the Scenario drop-down list displaying the selection of the desired scenario.
  4. On the InfoWater Pro ribbon, in the Domain panel, click Domain Manager.
  5. In the Domain Manager, for the Element Source, select DB Query.
  6. Expand the adjacent drop-down and select PIPES_2030.
  7. Click Add.
    The Domain Manager, with DB Query selected as the Element Source and PIPES_2030 selected.
  8. Expand the DB Query drop-down.
  9. Select the PIPES_EXISTING query.
  10. Click Remove.

The domain now contains only the pipes proposed to be installed by 2030.

  1. Click Add Connecting Nodes to add all nodes connecting to the proposed pipes to the domain.

Fireflow demands will be added to these junctions to determine if the proposed area can sufficiently deliver fireflows.

  1. Click Close to close the Domain Manager.

To set the fireflow value to test for the selected group of pipes:

  1. On the ribbon, InfoWater Pro tab, Edit panel, click Group Editing.
  2. In the Group Editing dialog box:
    1. In the Desired Element Selection group, ensure that Domain is selected.
    2. In the Element list, select Fireflow.
    3. In the Applicable Attribute(s) group, set the Fire Flow (gpm) value to 750.
    4. Click Apply.

The Group Editing dialog box with the fireflow options chosen to run them on the domain.

  1. Click OK to confirm.
  2. Click Close.

To configure and run the fireflow simulation:

  1. On the ribbon, InfoWater Pro tab, Analysis panel, click Run.
  2. In the Run Manager, click the Standard tab.
  3. Expand the Report Options drop-down.
  4. Select BASE, Base Simulation Report.
  5. Expand the Simulation Options drop-down.
  6. Select BASE, Base Simulation Option.
  7. Expand the Time Setting drop-down.
  8. Select BASE, Base Simulation Time.
    The Run Manager, with the BASE simulation selected for the report, simulation, and time options.
  9. Click the Fireflow tab.

IMPORTANT: While setting the conditions for the fireflow analysis on the Fireflow tab, be aware that when you enter a time or set a duration, you are technically creating an extended period simulation. However, this fireflow time setting will run a standard simulation for a specified number of timesteps. Only once it reaches the time specified will it apply the fireflow. Another caveat when doing this is that you lose control of your boundary conditions, such as your tank levels, which pumps are operating.

  1. Click Select Time.
  2. In the Select Time popup, click and drag the slider to set the time to 10:00 hrs.
    The Select Time popup with the slider at 10:00 hrs for the BASE scenario.

NOTE: The fireflow demands are not applied until hour 10 of the simulation. Everything before that time is considered to be a "standard" simulation.

  1. Click OK to close the Select Time dialog box.
  2. In the Run Manager, click Run.
    The Run Manager, Fireflow tab, with the Run icon highlighted.

The Fireflow report opens automatically in the Report Manager.

  1. If you are prompted to switch to the most recent output data, click Yes.
  2. Use the Report Manager to answer general fireflow questions, such as, can fireflows be supplied for the entire model?
  3. Right-click the Residual Pressure column header and select Sort Ascending.
    Report Manager for Fireflow analysis with Residual Pressure column highlighted

The lowest value is more than 20 psi, which is the residual pressure that was set in the Run Manager Fireflow tab. Therefore, fireflows can be supplied here.

IMPORTANT: These results are very limited because the fireflow demands are not applied until the hour specified, and you lose control over your boundary conditions. With these limitations in mind, it may be preferable to create a new scenario with the boundary conditions you want already specified, and then exclude the time settings and duration.

  1. When you are finished, click Hide to close the Report Manager.