All Questions
62
questions
1
vote
0
answers
39
views
QGIS: Further subdivide sub-catchments based on DEM
I have a DEM and a vector layer with existing hydrological sub-catchments. Is there a way in QGIS to further subdivide the sub-catchments based on the DEM?
- 85
0
votes
1
answer
145
views
Generate a very accurate mask showing where rivers and streams are using a DEM in QGIS
I would like to create a mask layer to show what the specific widths of a river or stream would be with certain variables. I'm using a high quality 1mx1m resolution DEM. I am able to do some things ...
0
votes
1
answer
51
views
Validating that the smallest channel extracted using ArcMap (Hydrology toolbox) from DEM is the first-order stream
In ArcMap, the 'Hydrology' tool under the toolbox 'Spatial Analyst' can be used to extract the stream network, as described in detail here: extract streams from DEM. One step consists of using a ...
- 141
1
vote
1
answer
175
views
Finding average depth of filled sink using ArcGIS Pro
How to find out the depth of a filled cells (filled using "Fill" tool for a DEM)?
I have a DEM (50m resolution) for which I used "Fill" tool of the hydrology tool of ArcGIS Pro to ...
- 319
2
votes
0
answers
127
views
Calculating upstream (contributing) area for >10,000 points using Python
I would like to create polygons of the contributing area for > 10,000 points.
I have all information that I need for this, including a 30m DEM, a river network (LineString geodataframe file) and ...
- 215
1
vote
0
answers
390
views
Python library for hydrology calculations for multiple points
I have a DEM (TIFF) with multiple points, which mark wells (right term?) of an underground pipe network:
I was wondering if there is a Python library which uses the elevation of the DEM to generate a ...
- 89
3
votes
0
answers
39
views
LiDAR derived streams - map scale
Historically, streams were defined by the map scale. For example, for a map with a scale of 1:24,000 would mean that the streams identified on that map would be 1:24,000 streams.
With streams that are ...
- 31
0
votes
1
answer
34
views
Identifiying the levels for streams derived from DEM
I am using GRASS GIS and I have been able to identify the various water-flow channels / streams using the documentation from r.watershed.
Now I wish to identify the levels of the streams. For example, ...
- 318
1
vote
3
answers
154
views
Issue with delineation using dem because of a DAM
I have a high-resolution DEM which I use it delineate watershed.
I am getting the delineation like this
The main branch is not getting delineating till the source.
So I used a hillshade to check the ...
- 421
2
votes
1
answer
118
views
Methods for burning depressions (not rivers) in a DEM
I am using a 2x2m DEM to simulate runoff on a 2D hydrodynamic model. After a baseline simulation, I am interested in evaluating the impact of adding depressions in specific areas that may work as ...
2
votes
1
answer
583
views
How to find out which areas are affected by flooding due to heavy rain?
I'm working on a little project to visualize affected streets of flooding due to heavy rain. I already got a DEM for my study area and filled the depressions with r.fill.dir.
Since I never worked on ...
- 21
3
votes
1
answer
767
views
QGIS: Burning stream network (catchment area)
I need help from stackexchange because of a DEM correction problem...
I have a DEM with a 5 meters resolution where one of the main river is cut by a large highway. In order to delete that topology ...
- 341
0
votes
0
answers
1k
views
Watershed delineation using hydrological Python library
We would like to delineate watershed polygon for a given pour point using hydrological Python library.
Until now, we have tried these libraries:
pyshed
Grass (r.watershed)
Whitetoolbox
We have ...
- 11
1
vote
0
answers
217
views
Get catchment area of a lake polygon in R
I have several DEMs as geotiff files which I load into R using raster::raster. Additionally, I have lake outlines (located within the DEMs) in the form of shapefiles which I load into R using raster::...
- 43
3
votes
1
answer
420
views
Apply volumes to points on a raster DEM in QGIS
I am trying to create a flood inundation map in QGIS from known flood volumes at specific points across a raster DEM. I could potentially do this manually for each individual point using contours ...
