Watershed Delineation

[Sean Spencer]

What is the output supposed to look like after you run the watershed delineation? I already clipped the data to the extent of the Big Cottonwood outline and when I ran the delineation the entire thing was one color? and there is just one value under that layer = 0?

[Matt Engbring]

Is this for lab 8?

On Mon, Apr 1, 2013 at 10:23 PM, Sean Spencer <seansp...@gmail.com> wrote:

What is the output supposed to look like after you run the watershed delineation? I already clipped the data to the extent of the Big Cottonwood outline and when I ran the delineation the entire thing was one color? and there is just one value under that layer = 0?

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[Shannon Wing Belmont]

Hi Sean,

Clipping the DEM to the AGRC watershed shapefile BEFORE you run the delineation is problematic in that the watershed will be limited to the cells available in the clipped DEM. You should run the watershed delineation tools on the original (full sized) DEM (fill, flow direction, etc.) so you can compare your results with the AGRC watershed shapefile or any other source you want to ...

The results you describe are correct. The watershed raster output will be a binary raster: true or false, in the watershed or out of the watershed.
You can symbolize the raster by assigning No Color to the false values (outside) or do a raster to polygon conversion and turn the raster watershed into a polygon. This will give you more symbology options.
Before running the raster to polygon, you might want to reclassify the raster and set the false values to NoData. Or you can use symbology options to not display the false values...

[Quinn Hall]

Sean (and Shannon )

I understand Shannon's response, and the reason behind it, but I think the instructions in the .pdf strongly indicated that clipping before running the tools was a good idea - ie: "add the Big Cottonwood watershed shapefile you used in lab 7 to orient yourself" and then "It may be quicker and cleaner to run the morphometric analyses in task 2 if you clip the DEM to the area of interest".  

I read it the same way you did Sean...

quinn

[Shannon Wing Belmont]

Quinn,
You are absolutely right.
I've amended the lab for clarity. Thanks for pointing out the specifics of the misleading text.

[Alice de Anguera]

Hi all,

You're not alone. I misunderstood as well. I guess I'll be starting over (sigh). At least I hadn't gotten much farther than this.

Alice

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From: Quinn Hall <qwh...@aggiemail.usu.edu>
To: usu-nr-...@googlegroups.com
Sent: Tuesday, April 2, 2013 9:47 AM
Subject: Re: Watershed Delineation

[Fidel Zebadua]

All right, so what do we do first so?

[Alice de Anguera]

Just follow the instructions and make sure you don't clip anything until part 2.

Alice

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From: Fidel Zebadua <fidelz...@gmail.com>
To: usu-nr-...@googlegroups.com
Sent: Wednesday, April 3, 2013 11:52 PM
Subject: Re: Watershed Delineation

[Shannon Wing Belmont]

I updated the instructions... took out the bit about clipping.

Start with the 10m DEM for Big Cottonwood Canyon, run the Fill tool on it, run the Flow Direction tool on the Filled DEM etc.

[Jason D Jones]

Can anyone walk me through snapping to pour point tool, I doesn't seem
to do anything? Also, when calculating the pour-point values (the lab
says use "integer") so you can access the attribute table, which I
did, but I don't have access to the attribute info (lab 9a)

> On Thu, Apr 4, 2013 at 8:17 AM, Alice de Anguera <alicede...@yahoo.com>

> Shannon Belmont
>
> Quinney College of Natural Resources
> Utah State University
> 5210 Old Main Hill
> Logan, UT 84322-5210