ArcHydro - initial error, a setup query

[RichardMorris]

Hi - I've been invited to work on a project in which I've been identified as the wetlands specialist. This is an optimisitic title but a good opportunity to learn. I've started investigating ArcHydro and will hopefully use it to identify aeas of our case study catchment suitable for wetland restoration, and then to quantify what impact they might have on flood mitigation. 

I hope someone can answer a couple of beginner questions. 

1) folder set up. I've read the Arc Hydro best practice notes, just not sure if I'm setting up the separate folders for each run I want to do in the most efficient way. In the Arc Hydro Dendric Stream Unknown Terrain tool (where I'm starting, as per the online videos), I'm going through each box and pointing the tool to a new folder I've created on my harddrive for each run. Screenshot attached. This is quite labourious - is there a quicker way?

2) Point Delineator tool - again, I'm next looking at this tool because the intro online tutorial moves to this one. Its giving me an error after i use the pencil to identify a point. Note I have pointed the Inputs to the tifs I've just created in 1) above, but for for Input Adjoint Catchment Feature Class I wasn't sure, so selected the case study boundary feature. I'm getting this star icon when I select the pencil to input the points, which doesn't match the red point in the tutorial. Screenshot attached. Any guidance much appreciated. 

Thanks for any help. I'm sure there'll be more.

Richard 

[DeanDjokic]

9/14/24

Richard,

Good luck with your wetlands project.  There is Wetland Identification Model component of Arc Hydro if your project will require identification of wetlands (and you have data to support the ML approach to doing it).

As far as your questions go:

1. Project folder setup is usually tied to the underlying DEM and terrain preprocessing you are doing.  You will set one project per area of interest.  Terrain preprocessing tools (e.g. Dendritic Terrain with Unknown Stream Location script) will recognize the location of the input layer and default outputs accordingly (all output rasters will be in the same folder where the input raster is and vectors layers in the input gdb/fd if there is one or in the default gdb if not).  Unless you want to CHANGE the names or location of the output layers (I suggest you use defaults while you are getting familiar with AH tools), you do not have to do anything – just run the tool.  So the recommended approach is (I am keeping it “simple”):
   1. Create a new Pro project (e.g. aaa.aprx) in an empty project directory (e.g. xxx).  Do NOT let Pro create a sub folder – so your aaa.aprx and aaa.gdb will reside in the xxx folder.
   2. In the xxx folder, create “Layers” folder and copy your DEM into it (ArcHydro1DEM).  I noticed that your DEM is in grid format.  While that is fine, you can convert it into .tif – gives you more flexibility.
   3. Add the DEM to the Map.  Open Dendritic Terrain with Unknown Stream Location tool.  Select ArcHydro1DEM as your Input DEM.  All other output names should be auto-populated.  If you hover over the output field, it will show you the full path to the output layer.  For rasters, that should be something like xxx\Layers\ and the raster name, while for the vectors, that should be xxx\aaa.gdb\Layers and the feature class name.
   4. Run the tool.
   5. Terrain preprocessing for an AOI needs to be done only once.  Then you can use it as many times to support analysis in that area as described below.
2. Watershed delineation.  I suggest you use “Watershed Delineation” tool (in Watershed Processing toolset) instead of Point Delineation.  It gives more options on snapping and can handle deranged terrain delineation (although you are not doing it now, but might come in handy later on).  It also does batch point processing.  Point Delineation is handy for quick exploration.  Follow this workflow:
   1. Create a new point feature class.
   2. Digitize one or several points into it (use standard edit tools in Pro for that – I also suggest that you turn the snapping on and snap your point onto the stream feature class).  This will be the “Batch Point” feature class you will use as input into the Watershed Delineation tool.  You can also use an existing point feature class with points of interest (if you have it).  For each point, there will be a resulting watershed saved the output watershed feature class (so for 5 input points there will be 5 polygons). 
   3. Run Watershed Delineation tool.  The Adjoint Feature Class will be created as part of process #1.  If you keep default names, Watershed Delineation tool should pick them all up.  You can leave the last two entries (related to sinks) empty – they are optional.  Note that as output, you will also get an output point feature class – that will include your input points but snapped onto the snap stream raster (so your input point feature class is not altered).
   4. If you want more points processed, you can either create a new feature class and add points to it, of you can add points to FC created in #2a.  If you add points you will note that feature class has a field “IsDone” and is populated with values 1.  As you add new points, that value will be “Null”.  Running Watershed Delineation tool again, will process only those input points where IsDone <> 1, so only new points will be processed (and once processed, their IsDone will be set to 1).  So many options on how you can go about this.

Hope this works for you.

Dean

[RichardMorris]

Hi - many thanks for your reply and directions. I've run Dendric Terrain with Unknown Streams again.
[cid:image001.png@01DB08DC.59696BB0]

While its running OK, I note a few errors. For example:
Error 002852 Output Drainage Line Feature Class: C:\RM\ES_Slow the Flow_GIS_MB1979\240905_ES_STF\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test.gdb\Layers\DrainageLine exists within geodatabase as C:\RM\ES_Slow the Flow_GIS_MB1979\240905_ES_STF\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test.gdb\Layers\DrainageLine. A feature class name can only exist once within a geodatabase, including within all feature datasets.

Error 002852 Output Catchment Feature Class: C:\RM\ES_Slow the Flow_GIS_MB1979\240905_ES_STF\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test.gdb\Layers\Catchment exists within geodatabase as C:\RM\ES_Slow the Flow_GIS_MB1979\240905_ES_STF\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test\240917_ES_STF_ArcHydro_test.gdb\Layers\Catchment. A feature class name can only exist once within a geodatabase, including within all feature datasets.
I thought I went to great care to set up a new folder for this test, can you suggest what I may be doing wrong?
Am looking at your Watershed delineation suggestions today.
Many thanks
Richard

[DeanDjokic]

Richard,

Based on the error message, it seems that there are some “old” feature classes in your target gdb (probably from previous runs).  Look into Catalog and delete any entries in the target gdb.  If you are at the very beginning of the AH process, you should not even have the “Layers” feature dataset within the target geodatabase (do NOT confuse the “Layers” feature dataset in the gdb with the “Layers” folder where your DEM is).  you should also check if there are any rasters in the ”Layers” folders that are “leftovers” from the previous run.  If there are, I suggest you delete them all before running the MB again (so you should have only the DEM in there).

Few additional suggestions:

1. Do not start your project with a number but a letter (e.g. instead of “240917_...” use “T240917_...”).  that should be done when starting the Pro project in how you name it – that will then generate the default gdb where the vectors are stored.
2. Cut down the name (length) of your folders and get rid of the “spaces” in the folder names (between the “C:\RM\ES_Slow the Flow…”).  How about parent folder like “C:\RM\AHTests\T240917_1” that will generate gdb “C:\RM\AHTests\T240917_1\T240917_1.gdb).  When creating the new Pro project, make sure you check off “Create a folder for this project” (lower left corner of the New Project form) otherwise it will generate another subfolder with the same name as the project name and that might not be necessary.

So I would start over with simpler names.

1. Create folder: “C:\RM\AHTests\T240917_1”
2. Create folder: “C:\RM\AHTests\T240917_1\Layers”
3. Copy your DEM (as .tif) into #2.
4. Create a new Pro project in #1 and call it T240917_1 (with the box checked off)
5. Add the DEM from #3 into the Pro project and save it.
6. Run the “Dendric Terrain with Unknown Streams” MB.

Dean

[RichardMorris]

Hi Dean
I followed your suggestions to the letter and am still getting the same errors:
[cid:image001.png@01DB098B.8916D280]
Error 002852 Output Drainage Line Feature Class: C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\DrainageLine exists within geodatabase as C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\DrainageLine. A feature class name can only exist once within a geodatabase, including within all feature datasets.
Error 002852 Output Catchment Feature Class: C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\Catchment exists within geodatabase as C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\Catchment. A feature class name can only exist once within a geodatabase, including within all feature datasets.
Error 002852 Output Adjoint Catchment Feature Class: C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\AdjointCatchment exists within geodatabase as C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\AdjointCatchment. A feature class name can only exist once within a geodatabase, including within all feature datasets.
Error 002852 Output Drainage Point Feature Class: C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\DrainagePoint exists within geodatabase as C:\RM\AHTests\T240918_1\T240918_STF\T240918_STF.gdb\Layers\DrainagePoint. A feature class name can only exist once within a geodatabase, including within all feature datasets.

[cid:image002.png@01DB098B.C7D54AB0]

[DeanDjokic · Accepted solution]

Richard,

We might have to do a deeper dive into your system.  Before we do that, please review: https://community.esri.com/t5/water-resources-blog/reporting-arc-hydro-tools-issues/ba-p/1176263 and the referenced doc on how to report Arc Hydro issues.  Collect the information from that document, and send it together with the DEM – as zipped file (you might have to place it on some shared drive or I can send you a link to one if needed) - directly to me at ddjokic@esri.com.  I’ll have a look and check if there is an issue with the data.  In the meantime, you can try to execute individual steps from the model to see if there is something else happening beforehand.  In general, that is a better approach than running a “superbutton” when dealing with new area of interest or are getting into the tools. 

Dean

[RichardMorris]

Dean - thanks again for the help - this is resolved now.