Multi Part to Single Part tool

Question

I am trying to group parcels based on a common field that are also contiguous. I have used the dissolve tool to create larger polygons of the parcels that all have a common field. I would like to break up the features that share that common field, but are not contiguous with each other. Within the set of parcel data, there are small gaps where things like roads and streams are. These gaps do not represent legal boundaries of parcels. Because of this, when using the Multipart to Single Part tool, I am having groups of truly contiguous parcels broken up because the tool is reading the roads and streams as legal boundaries for the parcel. Is there a workflow that will allow me keep these dissolved polygons in tact while still creating separate features for polygons that are truly not contiguous? I've tried workflows that involve not dissolving the parcels by a common field but that seems to get me further away from a solution.

KimOllivier · Answer

We handle this by having a point layer of labels that relate back to the polygons. There is only one point for each property, but some properties are multipart. That doesn't matter because they still have a total area. You only get one label so it is placed in the largest part. You add labels when they have been exploded and then choose the largest one. Run a summary by max area and then select the largest, discarding the others.

If you want to get rid of the non-boundaries there is an aggregate tool.

AlexanderGray · Answer

Dissolve has a multi_part argument that should avoid having to multipart to single part.  However if there is a gap in the polygon then from a geometric perspective they are not truely contiguous...  Maybe a select feature by location with a distance and then unioning the polygons...