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LiDAR DEM is too detailed, catchments are too small

Question asked by dwilcoxars on Oct 30, 2013
Latest reply on Oct 30, 2013 by geonetadmin
I have a 1m DEM derived from LiDAR.  I go through the usual process -- Fill, FlowDirection, Watershed.  The result is that sometimes I'm getting only part of the catchment (see the attached screen shots.  The blue outline is from a survey of the catchment area -- which may not be perfect, but it will be close). 

It appears that there may be too much detail in the DEM?  Small rises and ridges that are stopping the flow when in reality it is not a barrier.  Is there a threshold setting I'm missing?  Or repeat the Fill (will this result in good data being smoothed out as well as the bad?) 

I'm sure there is more artistry to be applied -- I just don't know what it is!  Any help would be appreciated.

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