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This Technote describes the process by which a user can import demand information from a spreadsheet using Modelbuilder, into Junctions or Hydrants. This article assumes Bentley WaterCAD or WaterGEMS V8i (08.11.XX.XX). The process is slightly different in V8 XM (08.09.XX.XX).
NOTE: if you'd like to include a visual representation of the customers associated with each individual demand, use the Customer Meter element instead. See this Webinar on the workflow of importing with Modelbuilder and using Loadbuilder to allocate to junctions.
In WaterCAD and WaterGEMS, demands can be entered as a base flow plus a pattern, or as a unit demand type and count. Also, multiple demands can be entered for each node (junction, hydrant, etc.). An exception would be the Customer Meter element, which is used for a 1:1 representation of all demands.
If your demand data is contained within an Excel Spreadsheet and you have a field that contains labels that match your model's node labels, you can use the Modelbuilder feature to import them. For example:
Note: If your demands are in shapefile form and you want to import them into junctions or hydrants, you should use the Loadbuilder tool, which can utilize the spatial information contained in the shapefile to assign demands, using many different methods.
If you attempt to import this information using Modelbuilder, you may end up with the following unexpected results:
This is due to the user selecting "junction" as the table type, which only provides read-only "demand" attributes to link your data to.
Note that when you import demands using this process, they will override any previous demands assigned to those nodes included in the spreadsheet. So, this process cannot be used to 'update' an individual demand for nodes that have multiple items in the demand collection. All of the demands that should be present for a particular manhole should be included in the spreadsheet when using this process.
Note: if you have WaterCAD or WaterGEMS V8 XM Edition (08.09.XX.XX) then the following Modelbuilder steps will be slightly different, as that version is older. The basic process is the same though.
Automated importing of demand patterns is only recommended if you have a large number of them that would otherwise take too long to enter (even with copy/pasting the columns of data). For steps to use Modelbuilder to import demand patterns, see this article:
Importing Demand Patterns Using Modelbuilder
If you want to see every customer meter, instead of lumping multiple demands into a single node, use the Customer Meter element. See this Webinar on the workflow of importing with Modelbuilder and using Loadbuilder to allocate to junctions
Can demand data be exported to an Excel file for use in another model?