Using LoadBuilder to assign Customer Meters to the nearest pipe using taps and laterals

  Product(s): WaterGEMS, WaterCAD
  Version(s): CONNECT Edition
  Area: Modeling


In earlier versions of WaterGEMS and WaterCAD, LoadBuilder could be used to assign Customer Meter elements to the nearest junction. With the introduction of taps and laterals in the CONNECT Edition release of WaterGEMS and WaterCAD, tap and lateral elements can be used to assign Customer Meters directly to the pipe and distribute demands to the adjacent nodes. The previous workflow assigning the Customer Meters to nodes is still valid. However, LoadBuilder can now create laterals when assigning the Customer Meter to the nearest node, though the lateral can also be added manually or through ModelBuilder if that is desired. The steps to assign a Customer Meter to a node is discussed in the link above. Below are the steps to assign to the Nearest Pipe using Taps and Laterals.


  • As of version and later, lateral link elements do not count toward your pipe limit.
  • Customer meters and their attached tap and lateral will be assigned based on the nearest pipe, perpendicularly. If the intersecting point is within 10 feet of the start or stop node, then that node will be consider as the nearest element and the customer meter will be assigned directly to the junction. A common situation would be a cul-de-sac as shown below on the right.



Benefits of using Taps and Laterals with Customer Elements

1) Potential reduction in the number of pipes in your model, which can have licensing benefits. A tap node is only associated with a pipe (does not split it), so, one pipe could be used instead of having to split it with a junction, yielding two pipes.

2) Better match with a GIS. Including laterals enables you to have a more complete, one-to-one match with your GIS, both visually as well as by way of tracking of these components alongside other hydraulic elements.

3) Better accuracy of demand distribution. When using taps and laterals, the customer meter demands can be distributed to the end nodes based on the position of the tap. There are options in the Loadbuilder wizard when importing and creating taps and laterals.

4) Better calculation performance compared to the use of explicit pipe elements as laterals. Hydraulics are not calculated in the lateral (pressure, velocity, headloss, etc) so a performance increase can be seen compared to the use of pipes.

Steps to Accomplish

These steps assume the Customer Meters are already present in the model. If you have not added them yet, you can do so manually or using ModelBuilder

This layout shows three Customer Meters that are currently unassigned to a hydraulic element. First, we will consider a case where the Customer Meter is assigned to the nearest node.

Assign Customer Meter to nearest pipe

Open LoadBuilder by going to the Tools tab. Click the New button in the upper left of the dialog to create a new connection. Select the Customer Meter Load Data option on the left side of the dialog. Since we are assigning the customer meter to the nearest pipe, select that option from the selections on the right, then click Next.

In the next screen, you will select the Pipe Layer, Node Layer, and Customer Meter Layer. This is basically telling the program which elements the Customer Meter may be associated with.

Next to the Pipe Layer option, click the ellipsis ("...") button, which will open the "Select a Layer" dialog shown above. For this case, we will choose "Pipe\All Elements," which means that all active pipes will be considered.

Note: If a node is inactive, the Customer Meter cannot be assigned to that node. Only elements active through Active Topology will be considered for associated elements.

Note: if you do not choose to create taps and laterals, the customer meters will be assigned directly to the nearest pipe, and the associated demand will be distributed to the end nodes based on the selected "Load Assignment" method. In earlier versions (V8i), customer meters would be assigned to the end node adjacent to the nearest pipe - the ability to do this again is being evaluated for a future release via Enhancement # 1052398.

In addition to selecting the Pipe Layer, you will also need to select the Load Assignment. The default setting is Closest Node, but you can also choose to weight the demand between the end nodes of the pipe, distribute the demand equally between the end nodes, or apply the demand to the farthest node.

Next, click the ellipsis (...) button next to Node Layer. All node types that can have a demand applied to them are available, and you can choose a selection set if desired (customer meter demand cannot be allocated to nodes that are excluded from the chosen selection set). In this example case we will choose "Junctions\All Elements". Finally, do the same thing for the Customer Meter elements. You also have the option to exclude customer meters that already have an associated element, but may not have a lateral or tap. To do this, click the "Exclude unconnected Customer Meters that already have an Associated Element." 

Lastly, you will want to select the option "Create taps and laterals for Customer Meters that are not connected." This will assure that the necessary elements are created to correctly associate the Customer Meters to the pipes via a tap and lateral.

Click Next and see the results that LoadBuilder has calculated. Notice in the screenshot below that two of the Customer Meters are assigned to one pipe. It is possible to have more than one customer meter assigned to an individual element.

Lastly, you will need to create a label for the LoadBuilder connection. You will also need to either update an existing Demand Alternative or opt to create a new alternative.

Click Finish and the LoadBuilder will assign the Customer Meter to the nearest pipe, as well as create the taps and laterals to complete the connection.

Note: By default, the demand will be split evenly between the upstream and downstream node. If the pipe is attached to a node that cannot have a demand, such as a valve or a pump, you will need to reattach the customer meter to a junction instead of the pipe. However, you can define the distribute by assigning a value to the Demand Distribution (Start) property field.

Reassigning taps to a new pipe

During the process of analyzing a model, you may need to associate an existing Customer Meter to a different pipe. If that case arises, you can use the following workflow. First, you will need to drag and drop the Tap element to the pipe that the Customer Meter should be associated with. In the screenshot below, the tap has been moved from pipe P-20 to pipe P-260.

Notice the dashed line that is connected to the tap element and P-20. This means that the tap is still associate with P-20. In order to associate the tap with the correct pipe you can right-click on the tap element and choose Attach.

If there are multiple taps that need to be reassigned after moving them, you there a batch tool that will do this as well. Go to the Tools tab. In the Tools section, select More > Assign Taps to Links.

This tool is used to batch assign taps to pipes when there is no current association. For instance, if you manually added the customer meters, taps, and laterals, there may be no true association between the elements. The Assign Taps to Links tool will assign this. However, it can also be used to reassociate taps that are currently associated to a different pipe. To apply this, select the option "Also process taps that already have an associated link" from the Options section of the Assign Taps to Links tool. When you click OK, the tap will be reassigned to the new pipe. 

The tap is now associated with a new pipe. However, the customer meter is still assigned to the old pipe. You can change the association manually in the Customer Meter properties. You can also use LoadBuilder to update the association. Using LoadBuilder, you can run the existing connection. When you are on the screen where you assign the pipe, node, and customer meter layers, uncheck the box for "Exclude unconnected Customer Meters that already have a valid Associated Element." Click Next and complete the LoadBuilder process. Once you are completed, you should see the associated pipe for the Customer Meter is the same one that the tap is connected to.

What if I have tap coordinates stored in the Lateral point feature?

In some cases, your GIS may only include the customer meter location, but may store a set of coordinates of the location of the connection point (the tap.) As of, the following workflow can be used:

  1. Starting in a model without the customers, taps or lateral - import the customers in ModelBuilder using the set of coordinates representing the tap location (to import them right at the tap location)
  2. Run the LoadBuilder customer meter nearest pipe allocation method. This will assign the customers to the correct pipe since the customer elements are currently located at the exact tap location.
  3. Update the coordinates of the customers in ModelBuilder, using the set of coordinates that represent the customer location.

A note on Licensing

As of the version, lateral link elements do NOT count toward your total number of pipes/links, (checked against the number of available pipes in your license.)

See Also

Customer Meter elements and the External Customer Meter Data Manager

Finding customer meters not connected via a lateral

Troubleshooting and Understand LoadBuilder

User Notification: "Cannot distribute ##.#% customer demand to <Node Type> "<Node Label>" of associated pipe <Pipe Label>."