Problem

Node / Pipe is not connected to, or is isolated from, a boundary (reservoir or tank) user notification

Background 

This user notification indicates that there is not a physically connected source of water to supply the nodes indicated by the message. 

Solution

There are a few possible solutions to identifying these elements. 

1) You can right-click on one of the user notifications about the node not being connected to a boundary element and choose to "Select All Elements with Message ID xxxxx". This will highlight the nodes in the model that are not connected to a boundary. 

Another option would be to use Network Navigator. In Network Navigator, click the ">" button and select Network Review > Find initially Isolated Elements. Click the Select in Drawing button to highlight the elements in the drawing.

2)  Whichever method you choose, right-click n the drawing pane and choose "Create a selection set." This will create a selection set of the elements that are not connected to a boundary.

3) You may also want to create a new color coding for certain conditions, like the "Is Closed?" property for pipes or "Status (Initial)" settings for pumps and valves. Closed pipes, pumps, and valves can impact the connectivity.

4) Locate the source(s) of water in the model. For example, you could set their symbol size to a larger size in Element Symbology or set the Drawing Style for the reservoir or tank to "GIS".

The following steps are various troubleshooting steps you can take to identify why the elements are disconnected from a reservoir or tank. This will vary based on the model. 

5) If there are pumps or valves in your model, ensure that they the correct downstream pipe is selected. Pumps and some valves do not allow reverse flow. If the pump or valve is reversed, this could impact the connectivity of the elements downstream of it.

6) Locate inactive pipes by going to Tools > Options and on the Global tab change make sure the "Display Inactive Topology" checkbox is checked and set the color to something identifiable. Go back in to the model and locate if there are any inactive pipes that connect to the water source, the pipes will be ignored in the calculation and could impact the results.

7) Go to View > Network Navigator and click the " > " icon. Choose "Network Trace" > "Trace Downstream". Select the reservoir or tank that is the upstream element to start tracing from. This will create a list of elements that you can highlight on the screen. Note: If you have more than one boundary/source, you may need to repeat this step for each source.

With the elements highlighted in the screen, either from the Trace Downstream query or simply from the Find Initially Isolated Elements query, look closely at the highlight areas. If pipes are not closed or inactive and pumps/valves have the correct downstream pipes, look for areas where nodes appear to be connected to a pipe, but are not, as depicted here:

If you find a case about this, you can connect an individual node to the pipe by right-clicking on the node and choosing Split Pipe. There is also a Batch Pipe Split tool that will perform this for multiple nodes within a given tolerance of a pipe.

See Also

Using batch pipe split to fix nodes that overlay a pipe instead of connecting to it