Combine polygons based on zoning code to make larger overlaying polygons

HanRit

Hey y'all, I had a coworker come to me with a map that was made by a previous employee that shows our zoning polygons as larger overlaying polygons. However, when I used the dissolve or merge tool, this just combines the records in the table and gets rid of some lines between touching like polygons, it doesn't create whole new polygons that extend outside the boundaries of the previous shapes. We have no more insight on what the user did to make this. Does anyone have a guess at how the combined one was created? Maybe dissolve/merge and then another tool?

 

Update: I tried Aggregating Polygons but the it did not work properly. Some of the shapes got the right polygon around it but others were merged into a different category all together. The screenshot AggregatedZoningLayer shows the aggregate on the bottom and original zoning on top to see the comparison. They have the same symbology properties.

AggregatedZoningLayer.PNG

CombinedZoningLayer.png

OriginalZoningLayer.png

EricIronside_5-1619808951558.png

abureaux_1-1736539630132.png

abureaux_0-1736539614446.png

danretired

vector approach:

• buffer the features by a distance sufficient to close the gap between adjacent buildings
• dissolve the buffer
• buffer by the negative of the distance used in the first bullet to shrink the outer boundary of the dissolved buffers

You will have to repeat as needed to get a solution that is suitable to your purposes.

Raster solution

• convert the vector to raster using a cell size appropriate to your ground distances
• assuming that the black outlines are the areas you want to remove, reclass that value(s) to nodata
• use Nibble (Spatial Analyst)—ArcGIS Pro | Documentation to fill the intervening spaces between adjacent buildings

repeat as necessary

Alternate solutions, will be as cumbersome and as inadequate as your desire for perfection rises, hence, union adjacent features and remove/add/move vertices until you get what you want, pair by pair