Mergin lines together?

[AmyAtangan]

Hello Everyone,

I was hoping someone could help me with a problem my group is having. We have a roads dataset that has quite a few tiny overlapping road segments that we want to get rid of. These road segments are directly on top of or overlap portions of other road segments. In the past, I have selected these lines and used the merge tool under the Editor menu to get one long continous road. In 10.1, when I try to do this they merge into one feature attribute wise but topology wise they are still overlapping features. This is reflected in the shape length column.

So for example, if you draw a line 100 ft long and then draw a second line on top of the first that is 50 ft long. In the past after hitting the merge button in the editing toolbar, these two lines would have the total length of 100 ft. Now in 10.1 the total length is 150 ft. Then when you run topology it creates a Must not Self Overlap error. 

Is there a work around for this? Any help is much appreciated!

[JohnSobetzer]

You could first planarize the lines and then merge them.  That does require ArcInfo and excessive mouse clicks but ArcGIS loves extra mouse clicks.  Another clumsy workaround would be to union them and then delete the originals, but the new line does lose the attributes so you have to use a method to transfer them.  More clicks.

The merge tool is creating overlapping multipart lines; you can see that not only in the length values but by using the explode tool on the merged lines to get back to their original two single part status although now with shared attributes.  There's probably a reason for this even if we don't like it in this case.  Maybe the Editor tool should offer a dissolve (to singlepart) or unsplit tool that works on just the selected lines in an edit session as an optional way to edit.

I would guess the ESRI recommended approach would be to have your lines in a geodatabase feature class in a topology with a must not overlap rule. Then the errors will be identified after validation and then you can use the topology fix tool subtract option to get rid of the unwanted portion.

You could also rely on geoprocessing tools like the dissolve or unsplit lines, which are great for processing lots of errors all at once, but they don't allow edit by edit work.