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I have been tasked with editing lines to more accurately follow rivers according to a LiDAR layer. I am currently editing the vertices that are not accurately aligned but there is just way to many lines. I was wondering if there was a tool in ArcGIS Pro for this.

If there is not is there an easier way to edit lines?

Edit vertices is slow and reshape is the only free drawing tool I have found so far and this is not the correct purpose for it.

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  • Is your LiDAR water classified? Should your tide line follow the water or do you have varying tide levels? You may be able to generate an outline of ground (water is sometimes not present due to reflectivity) then take the inverse... what kind of accuracy are you expected to achieve? May 4, 2023 at 0:11
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    Hydrology tools designed for this and work well, providing there are no depressions in your elevation model or they are very small. It's completely different task if there are large depressions (usually upstream of the roads)
    – FelixIP
    May 4, 2023 at 0:18
  • @MichaelStimson I don't need 100 percent accuracy but there are obvious spots where I can see where streams are and so it be nice if they I could get lines in those channels. What do you mean by classified?
    – jimbybob1
    May 5, 2023 at 15:29
  • @FelixIP Thank you for that! I have found that this is most likely the best solution. I have found hydrology tools that produce a differently shaded raster that highlights where rivers and channels are but I don't know how to convert theme into a line. Unfortunately, I am dealing with some mountainous areas.
    – jimbybob1
    May 5, 2023 at 15:32
  • asprs.org/wp-content/uploads/2019/03/LAS_1_4_r14.pdf page 22 describes the basic classification, page 33 has more advanced classification. When processed from a scanner all records are class 0, the next step is usually automated ground/non-ground, followed by automated veg/building classification, after these steps the manual work starts with ground surface improvement which may or may not include pulses occuring within water to be classified as 'water' (class 9), generating a class 2 & 9 raster followed by vectorization could save a lot of work. May 8, 2023 at 4:39

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Procedure of using Spatial Analyst Tools\Hydrology is straightforward:

enter image description here

I am guessing that what you call 'differently shaded raster' is an output of Flow Accumulation. If this is true, you are close.

Point 3 in above requires using of Raster Calculator. Example shown means that you are after all streams that drain catchment with area greater or equal to 10000 * cellsize * cellsize.

You are lucky (!) to deal with mountainous areas, because ArcGIS does great job in 'well defined topography':

enter image description here

Unfortunately, it fails big time at depressions:

enter image description here

I developed 100% automated procedure to handle depressions:

enter image description here

but I am not sharing it for free. Moreover you might not even need it, providing the depressions in your LiDAR are small.

In order to find their outlines use calculator expression:

Con("Filled">"DEM",1)

or:

Con("Filled">"DEM","Filled"-"DEM")

to compute depth raster.

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