I have two layers that I'm trying to conditionally join. One layer JUNCTIONS has junction IDs (NAME) and flooding volumes (Flood_cf) for each junction. I'm interested in identifying and symbolizing only the junctions with a flooding volume that exceeds a threshold (400 cubic feet).
The second layer CONDUITS contains pipe features with starting and ending nodes for each pipe. I would like to use the JUNCTIONS layer to identify the pipes that are surcharging (i.e. flooding). These are the pipes with starting nodes (INLETNODE) that match the NAMES from the JUNCTIONS layer which exceed the set threshold. Then, I would like to add a field to the CONDUITS layer in order to tag these pipes for symbology.
I tried doing a subquery (i.e. SELECT FROM (SELECT FROM) ) but I couldn't get the syntax to work. Alternatively, I could create a new feature class for the nodes that exceed the threshold, join the new layer to the CONDUITS layer, and export the results to a new layer. However, this process is tedious and generates a lot of extra and unnecessary files and fields. Is there a faster and a cleaner way to do this? I'll eventually have to create a model for this process because I need to run it on hundreds of files.

