Creating polygons from lines
If you have line features, you can create polygon features from them. For example, you might need to create parcel polygons from lot lines, lakes from shorelines, or street polygons from pavement lines.
There are several ways you can use line features to create polygon features. You can create a brand new polygon feature class, or you can interactively create polygon features in an existing feature class.
The tasks below are used to create new polygons in empty spaces rather than splitting existing polygons.
Creating a new polygon feature class
If you have an ArcInfo license, there are several geoprocessing tools you can use. The most common one is the Feature To Polygon tool, in the Data Management toolbox > Features toolset.
Creating polygon features in an existing feature class interactively
With an ArcEditor or ArcInfo license, you can use the Construct Polygons command on the Topology toolbar to create polygons from lines in ArcMap.