Finding overlapping polylines in same layer using ArcMap

Question

How can I find overlapping polyline features in a layer in ArcMap without writing any code?

I have a polyLine feature class in a personal geodatabase. It contains some features that overlap other polyline features in the same feature class.

If I use "Select by Location" to find these overlapping features, using two different layers based on the same featureclass, and use "Share a line segment with the source layer feature" from the dialog box in ArcMap, all features get selected because each feature overlaps with itself.

If I have 2 polyline layers in ArcMap based on one feature class, how can I find features from top layer which overlap with features of bottom layer that have different ObjectId?

Answer 1

I recommend that you try using the Intersect (Analysis) tool with one input.

According to How Intersect works (with my bolding):

Intersect can run with a single input. In this case, instead of discovering intersections between the features from the different feature classes or layers, it will discover the intersections between features within the single input. This can be useful to discover polygon overlap and line intersections (as points or lines).

Answer 2

In order to most easily select these errors, I suggest you create a topology with your feature class.

Just add the Must Not Overlap rule to the topology and it should highlight all the errors you are looking for. From here you can either merge or subtract the shared segments.

According to the documentation, the Must not Overlap rule "Requires that lines not overlap with lines in the same feature class (or subtype). This rule is used where line segments should not be duplicated, for example, in a stream feature class. Lines can cross or intersect but cannot share segments."

More can be found here:

http://desktop.arcgis.com/en/arcmap/10.3/manage-data/editing-topology/geodatabase-topology-rules-and-topology-error-fixes.htm#GUID-2154EDB0-E9C2-4B76-8F8D-94B81FE13D7B