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Have a look at this tool: CRWR Tools Optimized Pit Removal. When you correct sinks by simply filling them, you always end up with flat areas like that. If you fill just "minor" sinks (you can play around with what sinks to fill using sink evaluation and sink selection tools) your DEM will still have sinks, and the flow direction will still not be correct. The above tool both cuts and fills and tends to work better, in my experience, than simply filling. But it doesn't work on larger DEMs.
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03-09-2018
05:20 AM
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I had to do something similar. I was identifying how many points were upstream of a dam and ended up having to write a script to do it.
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03-09-2018
05:10 AM
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Hi David. I apologize if this is a silly question, but have you made sure its not just a symbology issue (symbolize by current display extent and zoom in to an area without streams)? I've had the raster calculator issue that you mention, but not the DEM reconditioning problem.
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01-08-2018
10:38 AM
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I figured out that the issue was with my flow accumulation grid. While it looked fine at first glance, I noticed that the maximum value was way higher than it should be and that these high value cells tended to occur at the headwaters of my stream network. It turns out that the issue was with "Create Drainage Line Structures" and "Adjust Flow Direction in Streams" tools. The former created a flow direction grid underlying my streams assigning flow according to the digitized direction of the stream network which, in my case, does not correspond to actual flow direction. So I ran flow accumulation on the flow direction grid without running "Adjust Flow Direction in Streams" and it worked. I'm now stuck on one of the following steps, but I'll find a better place to discuss that. Thanks for looking into this with me.
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07-26-2017
08:29 AM
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Hi Ian, I am using ArcMap 10.2.0.3348 and ArcHydro 10.2. The uncompressed size of the raster files are 376.39 MB (which seems small to me) with 10,753 x 9,176 cells. Everything is based off a 1m resolution Lidar DEM for an area of just over 50 km2. When I run flow accumulation with ArcHydro (from either the toolbar or the toolbox) it appears to keep running indefinitely. I have left it for a maximum of 2.5 days and when I open task manager I can see that memory usage is unchanging which makes me think that it crashed. When I ran the flow accumulation tool from Spatial Analyst with integer as the output format, it took 11 minutes and created a flow accumulation grid that looks totally fine to me. When I run the Spatial Analyst flow accumulation tool with float as the output format it also appears to run indefinitely although I haven't left it for more than maybe an hour. When I try to run the stream definition tool using the integer flow accumulation grid created with Spatial Analyst it tells me it has successfully completed and I get an empty raster that has values of 1 to 255. I have tried this with multiple different flow accumulation thresholds with the same result. I haven't seen this issue on any forums. The closest I've found is this one: https://community.esri.com/message/385236 Thanks,
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07-26-2017
05:47 AM
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I am also wondering about the difference between flow accumulation in Spatial Analyst and Arc Hydro because of this: https://community.esri.com/thread/198772-stream-definition-empty-output
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07-25-2017
12:15 PM
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Stream Definition- empty output I'm sharing this link here because I'm confused about where questions like this should go. I finally figured out that there is an Arc Hydro "group" and an Arc Hydro "space" and I don't know what the purpose of each one is. Thanks,
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07-25-2017
12:08 PM
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I am running stream definition and getting a raster with values from 1 to 255 rather than a simple 1 for all cells part of a stream. The raster is also completely empty (see attachment). I am using an integer flow accumulation grid as input which was created by using the flow accumulation tool in spatial analyst. ArcGIS hangs whenever I try to create a flow accumulation grid using ArcHydro, or create a floating point grid using spatial analyst. I'm not sure why the integer one shouldn't work, though. Has anyone encountered this issue before? Thanks,
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07-24-2017
10:08 AM
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I had this problem too. I was getting the same error message when running the tool from the toolbar, and a slightly different one when running it from toolbox (although I only did that once... I may have gotten a different message if I'd tried multiple times). I did 2 things to fix it. I removed a dash from the path name, and I deleted all of the files under the Scratch.gdb geodatabase that the tool created.
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07-20-2017
10:14 AM
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I am having this exact problem with both this tool and the create sink structures tool. I believe that what Jakub Sisak suggested is the cause. I have the Basic license only. I haven't upgraded my license to test this, but it seems like the likely issue. I wish the error messages could be updated to reflect this, I spent a long time searching for solutions!
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06-26-2017
08:53 AM
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If you burn the streams only in selected areas like at road crossings (like you are suggesting) or in particularly flat areas, where filling sinks eliminates the stream itself (like I may have to do) don't you then introduce sinks into the stream itself? Can that then be corrected by using fill sinks? Thanks,
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01-05-2017
05:08 AM
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Hi Fernando, Batch Watershed Delineation does often take a long time. I've found that I have to leave it overnight to run and that I can't have it run more than around 400 points at a time. This number might be different for you depending on your system resources. And I've also found that the help documentation for ArcHydro is severely lacking.
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07-18-2012
04:57 AM
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Go into Watershed Processing>Data Management Watershed Delineation. Set the batch points to your drainage line/roads intersection points (make sure they are singlepart). Once you exit the menu all the necessary fields will be automatically added to your points file and you can use it for batch watershed delineation.
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07-17-2012
11:35 AM
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The flow length tool will create a grid where every cell contains the distance from that cell to the outlet at the edge of the grid. If you are able to get the difference in values between two cells on the flow length grid that would do it (assuming you know that one eventually flow into the other). If you are looking for something more automated I'm not sure...
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06-21-2012
05:25 AM
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