I am having problems creating a negative 75m buffer with polygons which have regions narrower than 150m. To add some context, I have polygons which are created automatically out of enginnering data which are then defined as potential high-risk flooding areas. These geometries are notorious for their unwieldlyness. I have to use these Polygons in a 1:50000 scale map - but am not permitted to generalize...which is rather short-sighted. Below is a screenshot:

Polygon Structure

There are holes and very narrow areas making inside buffering impossible.

I need to buffer the polygons with a 62m buffer as we have a strict symbology guideline. My workaround was to convert the polygons to lines and buffer them. This works to a certain extent. The only problem is the line orientation. The Polygons need to be buffered inside. If I buffer lines I have to stipulate whether the line will be buffered to the left or right. This is not the same for each line and thus I have to work with each line individually to find out it's orientation.

Is there a workflow to somehow force the buffer to be produced and then dissolve and clip it with the original polygon outline?

I am using ArcGIS Desktop 10.6.

closed as unclear what you're asking by PolyGeo Jul 18 '18 at 23:39

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    I think this needs a picture of a polygon on which you are not able to get your desired result, along with what you want vs what you get, and the parameters used for the undesirable result. – PolyGeo Jul 6 '18 at 10:04
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    Feature to Line, buffer line with positive values and side type = Right or Left (right seems to work for me) – BERA Jul 6 '18 at 10:53
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    Agree with @PolyGeo, what are your polygons? Are they simple building foot prints or highly tortuous polygons with holes and therefore inner rings? Need more information. – Hornbydd Jul 6 '18 at 14:35
  • Not a solution but a comment. The opensource software SAGA-GIS handels the problem perfectly. It has created an inner puffer of all the polygons without crashing due to the narrow geometries. Free software which outperforms ESRI. – Robert Buckley Jul 9 '18 at 10:29
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    So what was the problem? Were you getting errors? I just tried running the buffer tool on some polygon data (rivers with islands) using a negative buffer size wide enough to collapse the geometry and it ran without error creating internal buffers when the river was wide enough. But I had a small sample dataset. – Hornbydd Jul 9 '18 at 11:58