Unable to get Zonal Statistics by table with DEM

Discussion created by paroulek on May 23, 2012
Latest reply on May 24, 2012 by erice-esristaff
Hey all -

I am having some trouble getting the national map DEM (10m) data to a point where I can analyze the average slope of a number of wetland polygons (+/- 4500). 

My plan of attack was to mosaic two USGS NED 10 m DEM quad rasters to cover my area (a watershed), calculate slope with the slope tool, then run zonal statistics as table to get the average mean.  I can then select out those polygons with a certain average slope.

The raster has no attribute table (zonal stats needs this), so I built an attribute table.  But wait, you can't build an attribute table on a 32 bit floating integer, so I copied the raster in to a 64 bit (also tried 18, 16 etc), then built an attribute table.  Still not working, just an empty table.  I have converted the polygon layer to raster (not ideal as some of the polygons are smallish), and no success.

This is beginning to take some of the fun out of this project.  Any help will be appreciated!