Error in executing catchment polygon processing with projected spatial reference

[rohitharitash]

I am preprocessing a DEM (cartoset v1) using arcHydro for basin property extraction. The issue is while processing catchment grid with spatial ref. GCS_WCS_1984, it is working fine. But when using projected re. ie. WGS1984 UTM ZONE 44N , I an getting

Sorting Attributes... Dissolving... ERROR 999999: Error executing function. Invalid Topology [Maximum tolerance exceeded.] Failed to execute (Dissolve). Failed at Wed Aug 24 06:17:33 2016 (Elapsed Time: 2.05 seconds) Error HRESULT E_FAIL has been returned from a call to a COM component. Failed to execute (CatchmentPolyProcessing).

I am using arcgis 10.3. I have to use WGS1984 UTM ZONE 44N because we cannot calculate slope without projection system.

my environment setting are attached.

[DanPatterson_Retired]

do you happen to have a bunch of small polygons?  Have you run a check geometry? get rid of the small ones and/or try to density the polygon boundaries before projecting.  If you intend to keep it in a geodatabase you might want to check those parameters, they don't seem to be fine enough

[rohitharitash]

HI , thanks for the reply. I cannot check for geometry because my input 'cat' is a raster. You are right about small polygons. I am clipping a very small area from the DEM. Can you suggest some pre-processing steps to over come the small polygon issue. I am also attaching the attribute table of my input 'cat'.

Thanks

[DanPatterson_Retired]

well that is an archydro bug, when it is trying to convert the raster to a polygon.  the only thing you could try is to filter the raster prior performing the analysis, you need to get rid of the small areas in the raster (probably only one or two cell regions