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Symbol levels for overlapping polygon layer?

March 19 2008 | 0 comments

I have a layer that contains polygon areas representing EMS coverages in Oklahoma. Some of these coverages overlap and some small EMS services are completely contained by others but they are all in the same shapefile (we want to have it this way for our ArcIMS site). I have tried to change the symbol level drawing order to display the small polygons on top on the map but it still will not do it. Do you have any suggestions? Attached is the shapefile of the EMS coverage areas.

Thanks for your help,

Mapping Center Answer:

One technique that worked for me right away was to use the "SHAPE_Area" (your "NewArea" works just as well) as the Unique Values category. This automatically sorts the data by value in the Table of Contents. The next step is to use Symbol Levels (from the Advanced button on the layer property Symbology tab) to display the features in that order. This technique works so-so for your data, in that there are a relatively small number of features - this method generates a unique color and Table of Contents entry for each polygon, which may have implications if you need to create or manage a legend.

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