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Spatial Analyst to create streams from LIDAR GRID

Question asked by vanjay011379 on May 25, 2010
Latest reply on Jan 6, 2017 by Lady_Jane
Hello,

I am attempting to create a series of streams from a 1 meter resolution LIDAR DEM in GRID format.

I am using ModelBuilder to create a workflow.  Basically, I do the following.

Run a fill
Run a low filter
Generate flow direction
Generate flow accumulation
Conditionally use only those with 100 cells of accumulation
Create stream links
Create stream order
Convert streams to features

I have attached my workflow (workflow.jpg).  It executes and outputs streams.  However, the streams are fragmented and appear as dashed lines that don't really connect. 

My map attachment (map.jpg) shows this.  Why does this fragmentation of the streams occur?  I want my new streams (in green dashes) to look something like the original streams (in red). 

I noticed if I run an aggregate (of 3 or 9 meters resolution cells), I get better connected streams.  Why won't this work with 1 meter resolution cells?

Again, why are the streams so fragmented?

Also, is my workflow correct?  Am I using the stream link, order and features operations correctly?  Should I even run a filter?

Thanks in advance!

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