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How To: Calculate the percentage of a polygon boundary that does not fall within a specified distance of other polygons

Summary

Instructions provided describe how to calculate the percentage of a polygon boundary that does not fall within a specified distance of other polygons. For example, how to calculate the percent of the city boundary that does not fall within 1000 feet of certain attractions.

Procedure

  1. For buffer features, use the Dissolve All option to make one feature. For more information on using the Buffer tool, see ArcGIS Desktop help topic: Creating Buffers.
  2. Use the Merge tool to merge the buffers of schools, churches and parks into one shapefile. Call the output 'Buffer_Merge.shp'.
  3. Dissolve the feature class. Uncheck the option to Create Multi-part features.
  4. In ArcMap, export the boundary layer to a new shapefile. Add the newly created shapefile to the map.
  5. Start an edit session. Set the target to the new boundary shapefile.
  6. In the Table of Contents, click Selection (or List by Selection). Right-click the Buffer_merge_Dissolve layer and select 'Make this the only selectable layer'.
  7. Use the black arrow tool from the Editor toolbar and select the BufferMergeDissolve feature.
  8. From the Editor drop-down list, select Clip. Select 'Discard the area that intersects' and click OK.
  9. Stop editing and save the edits.
  10. Open the attribute table of the clipped boundary layer. Navigate to Options > Add Field and type 'Area' into the Name field. Set the type to Double.
  11. Right-click the new field heading and select Calculate Geometry.

    Note:
    A message may display regarding calculation occurring outside of an edit session. Dismiss the message by clicking Continue.

    Select the Area property from the drop-down list, and select the Units desired. Click OK.

  12. Repeat steps 10 and 11 for the original boundary layer.
  13. Compare the clipped and whole boundary layer areas.