After importing elements through ModelBuilder, it appears that some junctions are overlaying the pipes without splitting them, which is causing connectivity issues. Is there a way to fix this?
This can occur for some cases when using ModelBuilder. This is because ModelBuilder will not split pipes that happen to intersect. ModelBuilder will create a junction at the end of the pipe that touches the other pipe, but will not split it. There are two ways to connect them. If you want to find pipe split candidates before splitting pipes, you can use Network Navigator to do this. In Network Navigator, click the ">" button and choose Network Review > Pipe Split Candidates. This can be useful if there are pipes that might be a pipe split candidate where you do not actually want to split. If using Option 1 below, you can put the features you want to apply into a selection set so that other elements are not included in the batch pipe split.
First, you can use a tool called Batch Pipe Split, which is found in the Tools pulldown. This allows you to split the whole model (or a selection set or subset of the model). This can be helpful when you have numerous pipe splits to do.
After going to Tools > Batch Pipe Split, you will get the dialog above. You can choose to use the operating over the whole model or choose a given selection set of elements. You can also set a tolerance for cases where the junction is close to but not directly overlaying the pipe. When you click Okay, the operation will run. Once completed, you will get a notification of how many pipes were split
When a pipe is split, it will create two new pipes. Both pipes will retain the properties of the original pipe, with the exception of the length of the pipe. The names given to the pipes will following the naming convention set in the Labeling tab of the Options menu (Tools > Options).
The second way to connect them is manually. If you right-click on the junction that overlaps the pipe, you can choose the option "Split". This will split the pipe as well. This is useful in you only have a handful of pipes you want to split.
Batch Pipe Split Crashes
Note that Batch Pipe Split is intended to be used on pipes that already have proper end nodes connected, but with other nodes floating on top midway along the pipe. It will not work properly (and may crash) if your model contains pipes with missing end nodes (try running the Network Navigator query "pipes with missing nodes"). This situation could happen for example if you imported your pipes using ModelBuilder but did not select the option to "create nodes if none found at endpoints". If this happens to you, you may need to create a new model and re-build using ModelBuilder with both the pipes and nodes selected, and with the "establish connectivity using spatial data" option selected. This will ensure the pipes are connected to the nodes. If you then still have nodes floating on top of the pipes, check to make sure there are not multiple (perhaps that had previously been caused by multiple ModelBuilder import attempts?) and then run the Batch Pipe Split tool.
Using Network Navigator