Performing a Multi-Trace Analysis

Step-by-step:

A multi-trace analysis is a batch process that runs multiple and separate source trace analyses for each individual trace. It allows you to track over time what percentage of water reaching any node in the network had its origin at a particular set of nodes. The source nodes can be any node in the network, including tanks or reservoirs. Internally, the program treats the nodes as a constant source of a non-reacting constituent that enters the network with a concentration of 100.

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

To set up the simulation options:

3. In the Model Explorer, Operation tab, expand Simulation Options.
4. Double-click WQ_CL, Chlorine Analysis.
   
5. In the Simulation Options dialog box, click Clone.
   
6. In the New Simulation Options popup, New ID field, type “WQ_MT, Multi-Trace Analysis”.
7. Click OK.
8. From the Quality tab, select Multi-Trace.
9. Ensure the Trace Node field is blank.
10. Set Multi-Trace on to All Storage.

Be aware that the All Storage option includes all tanks and reservoirs. When tanks are used as the source, all water leaving the tanks is attributed to the tank versus the source that provided it. If you were to choose All Reservoirs here, then the analysis would include only true water sources.

11. Click OK.
    

To view the multi-trace results without the Map Display tool:

12. On the ribbon, InfoWater Pro tab, View panel, click Reset Map Display.
    

To run the analysis:

13. In the Model Explorer, click Run.
    
14. In the Run Manager dialog box, Standard tab, set Simulation Options to WQ_MT, Multi-Trace Analysis.
15. Set Time Setting to WQ, Water Quality Analysis.
16. Click Run.
17. When the simulation has completed successfully, click OK.
    

To view the results of the multi-trace analysis:

18. On the InfoWater Pro ribbon, View panel, click Report Manager.
    
19. In the Report Manager dialog box, click New.
    
20. In the Output/Report Graph dialog box, Tabular Report, select Multi-Trace Report.
21. Click Open.
    
22. In the Report Manager tabular report, set the output time to 120 hrs.

This report details the percentage of water that comes to each junction from each source at the specified time. Nodes adding up to more than 100% receive flow from a tank that is supplied by the reservoir.

23. Click Hide to close the Report Manager.

IMPORTANT: The multi-trace function is a batch process that runs multiple and separate source trace analyses for each individual trace. It is not a simultaneous solution of multiple source traces; therefore, it is possible that the combined traces do not fully satisfy continuity, especially with tanks that experience both incoming and outgoing flows. So, it is important to understand that the total percentage of water combined from each source may not total 100%. You can use a trace analysis if you require more detail.