Is ther a limitations on dissolves?

Discussion created by bgfield on Sep 4, 2012
Latest reply on Sep 4, 2012 by dhoneycutt-esristaff
A colleague gave me a collection of rasters featuring SONAR data, which I converted to polygons via the raster-to-polygon conversion tool.  There were 50 rasters, and after converting them all I merged them into one file and then performed a dissolve based on a field containing two possible values ("sand" or "silt).  I expected two features in the resulting output, but instead I have four - two for "sand" and two for "silt.  The data was collected from a section of a river and it looks like the features are split in half; two of the features are on the top half of the river, and two are on the bottom.

My guess was that the polygons were just so complex (due to the conversion from raster) that Arc is just unable to put them all into the same feature, but I'm not sure if that was a limitation or not.  If that is the case, is there a workaround?