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Intersect Multiple overlapping road Lines

October 23 2009 | 0 comments
Categories: Map Data

I have a shapefile of 213 routes. Iin many areas the routes travel down the same street; therefore, they are intersecting or sharing a line segment. I am attempting to identify these areas where my routes share a segment by running the Intersect tool, but in some cases the intersect results in more than one route and I want to be able to show that multiple intersect. Is there a way to do that?

Mapping Center Answer:

What you really have is a topology problem.  You've got features that sometimes have overlapping segments. 

Create a new file geodatabase and a feature dataset that matches your shapefile's coordinate system, then copy shapefile into that location.  Create a topology and add rules that do not allow overlapping segments.

That will give you, in ArcMap, a guided tour of the segments that need attention.  You will then want to add either attributes that manage the alternate route numbers and route types,or a more complex Maplex stacking and label class regime.  You won't actually correct the topology "errors"--they are just there to guide you to the locations that need attention.

You could geoprocess this by selecting each route and storing it as a separate feature class, then put the collection of feature classes into the Feature to Line tool. That will break the lines at the ends of shared segments (a not so obvious but really valuable use for the feature to line tool). But you will have a lot of work to do in fixing the dataset (calculating fields, and deleting unneeded fields). My guess is the topology method is going to be faster and easier with only 213 routes.

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