Dissolving Lines

06-20-2012 02:48 PM
New Contributor II
[ATTACH=CONFIG]15386[/ATTACH]Hello.  I have a stream feature class.  The streams are divided into many, connected line segments.  I also have a layer of multiple polygons representing linear ROW areas.  My goal is to calculate how many continuous streams pass through the ROW.  My workflow has been: Intersect the stream line layer with the polygon ROW layer.  This produces a line layer representing only stream lines that fall within the ROW polygons.  My next step is to dissolve in a way such that all connected line segments become a single line feature and all unconnected line segments remain as individual features.  I used the Dissolve tool, and unchecked the Create Multipart option.  I expected this to dissolve all connected line segments into a single feature, but leave unconnected line segments as-is.  In areas where there is a stream confluence, this did not happen.  The connected segments remained as individual features.  I do believe the lines are actually connected; I zoomed in to something like 1:0.1 and they still looked connected.  Does anyone know how I can dissolve this stream layer so that all connected line segments become a single feature?

Below is a image of what resulted.  The numbered segments remained after I ran a dissolve.  I want to dissolve them such that these connected segments become a single line feature to represent a single stream crossing.

Thank you.
0 Kudos
1 Reply
Regular Contributor II
You cannot create branching line features. Dissolve will dissolve parts where there are only two lnes joining (what used to be called a pseudo-node).
Arc will not choose one path of the branch for you either.

This is what Multipart is for. The whole collection in your ROW area will be one feature, albeit not all connected topologically.
0 Kudos