Point Cloud to Bluespot, Stream and Drainage Basin (Catchment Area)
Why Geographic Information Systems Stack Exchange recommends it
GIS Stack Exchange users link it as a worked, open-source example of finding bluespots and catchments from LiDAR data in QGIS and SAGA.
Recommended by 1 people across 1 different months, 2018 to 2022.
What it is
A short screencast tutorial showing how to turn a LiDAR point cloud into a terrain model and then derive bluespots (terrain depressions), streams and drainage basins. It uses Danish elevation data with LAStools, QGIS and SAGA GIS, and is presented by Lene Fischer.
What people said
Recommends Marco · 2018-04 · Geographic Information Systems Stack Exchange · on “Locate wet patches using DEM”
The subject has a lot of atention among specialists and the number of tools available depends on the amount of work you wnat to put on it. The paradox is that you want to avoid wet areas while stormwater engineers are looking for recreational areas to use them as ponds and damping peak flows. There are three levels at which you can take your analysis: Mapping of low points, also known as bluespots mapping Mapping of runoff Mapping of runoff with the stormwater management system Bluespots are easy found by identifying depression in a DTM, under QGIS you have many alternatives, I would use the GRASS command r.fill.dir [LINK] from the Processing Toolbox , but there are more tools to do it. I ha
Cites overscoper · 2021-01 · Geographic Information Systems Stack Exchange · on “Hydrological Enforcement of culverts in QGIS”
I work on a farm and we are in the process of developing a surface drainage program for individual fields. I am using QGIS 3.16 and the publicly available 2020 QL2 LIDAR flyover of Indiana, and my goal is to create bluespot maps to help visualize the problem areas, with as much free and open source as possible. I've been able to teach myself quite a lot and have produced maps that are quite usable. However, these maps are highly affected by culverts, which are plentiful in the flat lands around where the drainage is most important. I have been able to find references to hydrological enforcement and burning streams, but I have not had any luck finding a clear set of instructions on how to bur
Cites EKOAndrew · 2022-06 · Geographic Information Systems Stack Exchange · on “QGIS: Identify depressions/bluespots in the landscape”
I'm looking for a way to identify depressions/bluespots in the landscape. I've tried using the SAGA tool "Fill sinks (Wang & Liu)" but for some reason all of the SAGA tools are greyed out and as soon as I run them they get an error and can't finish. If the analysis had worked I would then use the Field calculator on the filled DEM to calculate the bluespots/depressions. But since SAGA doesn't work... I haven't been able to find a solution for this problem so instead I'm now looking for an alternative method of identifying depressions in the landscape where water might accumulate during heavy rainfall for example. Any suggestions on how to create a map like the one I've added below? The Saga