I have produced two Hydro Networks (junctions and edges) for two Lidar tiles, and now I'm trying to combing these feature classes without destroying any of the attribute data.
(Attached: "Capture")
In the attached image I have my two sets of tile junctions/edges. I removed the Hydro (Geometric) Network in order to use ArcMap's topology functions. After merging feature classes (X junctions merged to Y junctions / X lines merged to Y lines) I performed a series of "X features must not overlap Y features" and "no pseudo nodes" topology corrections. Through this, I was able to combine all the junctions and lines AND preserve all the original attribute information (with newly-calculated shape lengths, since some of the lines had been combined).
(Attached: "Capture2")
The problem is, I don't know how to put these junctions and lines "back" into a Hydro Network. The reason I'm interested in doing this is to use Utility Network Analyst to show flow direction for each of the lines. Is the Network even necessary? I suppose I don't really understand the functionality of these Hydro Networks.