I have two polygon shapefiles, one is county boundaries and the other is the National Flood Hazard Layer that shows areas in the floodplain. The flood layer is an extremely complex and challenging file to work with. It has many polygons that have 1 million + vertices and many overlapping polygons (that shouldn't be).
My goal is to find the area of counties either covered by the floodplain polygons or the area that is not covered by the polygons. Here's what I've done so far...
I first tried using identity to and then summary statistics on the county and flood layer. Unfortunately because there are so many overlapping polygons my output is wildly inaccurate sometimes with more than 100% of the county being covered by floodplain.
I then tried using topology with the polygons must not overlap tool and the create feature error fix. Unfortunately this crashes arcmap every time I run it.
My next thought was to calculate the area not covered by any polygon hence bypassing the problem of overlapping polygons. I'm currently trying to turn the polygon shapefile into a raster to do this but its a slow process.
I have computers running ArcMap 10.2.2 and 10.3 with advanced licences.