12
Sometimes it is better not to use out of the box solution. This is why I suggest
Populate X an Y fields in node layer, convert them to integers, say cm. Create string field and populate it by concatenating string represantations of integers.
Do similar thing in links table for first point in the shape.
Join nodes table to links using latest created fields ...
9
Your stream network is only ever going to be as good as your DEM is. If there are issues in the DEM, the results may be less than optimal.
Besides that, the methods for sink / pit removal in ArcGIS seem to be less than optimal in specific cases (e.g. relatively flat wide areas in the DEM). Stephen Jackson of the University of Texas, Center for Research in ...
8
You will need to define your lakes as sinks (Create sink structures), and then use the ArcHydro function Adjust flow in lakes/streams/sinks. (These functions are only available in ArcHydro for ArcGIS 10.1, I have made a function that, with some modifications, might help you on the way if you are in 10.0.)
You can also erase (Extract by mask) the lakes from ...
7
I would recommend that you use the (free) extension ArcHydro Tools. It's got a lot more features and ways to tweak your results than the built-in functions.
There is a document here for 10.1 which outlines possible workflows. Although it's a bit different than in 10.0, it should give you a good starting point to get the idea of the software.
Unless you ...
7
Algorithms for performing stream network analysis all work in a similar way. These tools will use the D8 flow direction (Fdr) grid to navigate through a defined raster stream network (Str) using the network of flow paths defined by the D8 flow direction. Essentially what a link classification tool will do is scan the raster, usually starting from the upper-...
5
Yes, I would use ArcHydro. I found a document on this page (updated link thanks to @Polygeo) a while ago, that outlines some possible workflows (from the ArcHydro Team). There have been some changes compared to ArcMap 10.0 so for me it was quite useful.
5
I wrote a detailed answer to another recent question regarding extraction of streams from DEMs here. However, the gist of it is that when you extract a stream from a flow accumulation raster (upslope area) you are effectively saying that there exists a geomorphic threshold that relates the amount of discharge (upslope area is used as a surrogate for ...
4
I would use a simple model to iterate over each point, snap to the flow accumulation grid then compute the catchment. This would create a raster for each sub-catchment point. The model would be:
4
I found an answer to this on the ArcGIS Discussion Forums where Crystal Dorn back in 2007 says more or less the same as @GetSpatial:
The core Hydrology tools serve as a foundation for the ArcHydro
extension.
The ArcHydro extension helps with the overall workflow of building a
hydrologically correct elevation surface amongst other things. It has
...
4
I would like to defend RivEX and what its capable of. I have to admit I have a vested interest as I'm the developer behind it. Some very clever people (not me!) developed an algorithm that could compute Strahler order and RivEX uses this algorithm for assigning Strahler order. It's very fast and can handle highly threaded networks. I've thrown networks in ...
4
It appears that this is a fairly common error encountered when ArcHydro is run with data between the network and the local C: drive. See this site for further details:
https://geonet.esri.com/thread/89781
The solution seems to be in where the data are stored.
4
When you put an iterator in Model Builder, it is supposed to execute the entire model with every iteration. What I think you are looking for instead is to either write this as a python script, so you can better control the looping, or your other option would be to use a sub-model. What I mean is, set up just the part that needs to iterate as a model all by ...
3
From what I understand, you just have to assign fill, Fdr and Fac the name you want to name those raster! They will be automatically saved to the arcpy.env.workspace.
import arcpy
arcpy.ImportToolbox("C:\Program Files (x86)\ArcGIS\Desktop10.1\ArcToolbox\Toolboxes\Arc Hydro Tools.tbx", "archydrotools")
#Set Ouput Names
fill=arcpy.GetParameterAsText(0) + '\\...
3
Ssee http://grasswiki.osgeo.org/wiki/Creating_watersheds in the Wiki. With r.water.outlet you can calculate a watershed "backwards" from its outlet point.
Furthermore, see also http://grasswiki.osgeo.org/wiki/R.stream.*
The screenshot shows where to find r.water.outlet in "Processing" (former Sexante) in QGIS 2. Typing into the search field lists name ...
3
You can achieve this with a simple model. This question was asked here, for which I give a model showing how it can be done.
3
Check out these two step by step guides from my old lecturer on using arcmap to extract river profiles / drainage basins from DEMs, they're excellent!
http://www.geos.ed.ac.uk/homes/mattal/Topo1.pdf
http://www.geos.ed.ac.uk/homes/mattal/Topo2.pdf
Basically you need to create 'pourpoints' at the base of each river segment you want to calculate the ...
3
If you want to calculate streamflow from rainfall/precipitation events, a hydrological model is needed. HEC-HMS is a good & not that complicated model. You can use HEC-GeoHMS (addon for ArcGIS) to generate most of the inputs for HEC-HMS. A very good tutorial for both HEC-HMS & HEC-GeoHMS can be found here
http://web.ics.purdue.edu/~vmerwade/tutorial....
3
Topography is not the only factor that controls stream location. Steams can meander and cut into higher ground. This is particularly the can where the ground is made of alluvial sediments that are easily remobilised.
I should also say that SRTM data does not always locate the lowest ground due to its spatial resolutions and slope determination issues ...
3
You can use archydro tools. This tool will create unique identifier for each basin.
3
You have now provided an error from IDLE in a Comment to your Question which is that it is:
Traceback (most recent call last): File
"C:\Users\LG\Desktop\peiramata\pythotwo.py", line 9, in
import arcpy ImportError: No module named arcpy
The error you are seeing has been reported several times on GIS SE (e.g. Debugging ImportError: No module named ...
3
The content was migrated to GeoNet over the fourth of July weekend. A quick Google search turned up a relevant thread (read the top and bottom, because the password has changed since the original post), so GeoNet has been at least partially indexed by Google.
Note: I turned up a possible link to the old forums on a private GeoNet group, but it's not working....
3
Can I clarify, did you extract the basin for a specific point that you digitized? If so, did you use the Snap Pour Point tool to reposition your digitized point onto the 'digital' stream (i.e. the path of high flow accumulation derived from the DEM) as per the instructions given by ESRI? If so, this is likely your problem. The extraction of a watershed (or ...
3
To create the raster stream network you first threshold a flow accumulation raster, likely using the Raster Calculator or the Con tool. You're right that this will create a Boolean streams map of 1's and 0's. To break the streams raster into the various stream segments (links or tributaries) you would use the Stream Link tool using the same streams raster ...
3
Your workflow should get you what you need.
I'd recommend to use Con for the first two steps (then you can aggregate them into only one step).
I don't know of any existing tool that does these steps, but if it exists it's most likely to be in ArcHydro (never heard of Government toolbox though). However, this is quite a simple process involving only three ...
3
Let me know if this is what you expecting to see:
I'll post workflow.
3
This is a bit wonky:
ws = env.workspace = r"C:\Users\fractal\Desktop\python_teste\projecaoMiriab2.tif"
This code assigns the workspace, and the variable ws, to the folder housing your tif. So this line of code:
ArcHydroTools.FillSinks(ws, output)
tries to run the hydro tool with a folder as an input for a raster.
Your output looks like a folder. If so, ...
3
Here is a link to a Python tool to loop the surface volume tool in ArcGIS. You will need a 3D Analyst license to use this tool. You will need a single raster file for each of your sinks but it looks like you already have linework that you can use to clip out each of your sinks.
The tool takes as inputs user-defined graduations above or below a given ...
2
I got a little bit different error(s) while running Sink evaluation and basic deranged terrain processing.
Anyhow, these steps might solve other errors too so here's what helped:
I moved all of my data under C:\data\
I created new file geodatabase (named testing.gdb) under that folder
I increased the max number of unique values to render
I set out the ...
2
You should look into the Soil Water Assessment Tool (SWAT) for this type of analysis. It really depends on the soil types in your area along with temperature and topography. There are simpler ways to approximate your runoff (USLE method or the rational method), however it would be better if you could get more information.
http://swat.tamu.edu/
Good luck!
2
Burning the hydro network into the DEM is not ideal. It alters the DEM in subtle ways & does not create a proper hydrologically enforced DEM. Burning is basically enforcing a downward elevation change in the DEM to route flow downstream. Certainly, the resampling will have an effect depending on how it was done, I'm unclear why 5m? A mention of the DEM ...
Only top voted, non community-wiki answers of a minimum length are eligible
