merging/dissovling overlapping polygons in one layer into a single polygon

Discussion created by phigamma on Jul 8, 2013
Latest reply on Jul 25, 2013 by phigamma

I have question regarding polygons created through a buffer operation. I created a buffer feature from a road network centreline file, which consists of multiple sections. Around intersections and highway ramps for example, this resulted in a multitude of overlapping polygons (one for each element/link in the network). Now I would like to dissolve/merge those overlapping polygons into one so that each interesection for example is assigned a single buffer area while I want to maintain those polygons along single stretches of road as discrete features. I include an image below which hopefully explains what I am trying to say.

I have tried feature to polygon and intersecting the layer with itsef as well as a few other options but so far I have only succeeded in either creating one continuous buffer polygon for the entire network or generating a multitude of individual polygons for each area of overlap. I know that in editing mode I could select and merge specific polygons by hand but my network has over 23,000 links and checking them all for overlaps and editing those by hand seems, well, inefficient. I also thought about creating a topology but the only fixes available for overlapping polygons also seem to be to a) either delete areas of overlap, b) assign them to one of the participating polygons or c) turn them into new polygons (back to the multitudes). I am not worried about summing or maintaining attributes of the buffer polygons other than their location.

I could probably implement a python script that does exactly what I need but would not be able to fiddle around with one to adapt it myself.

Any helpul hints would be greatly appreciated!!