A watershed, also known as a catchment area or river basin, is the area from which precipitation flows into a particular river or watercourse and into which the river or watercourse drains. It is a natural hydrological unit defined by topographical features. Catchment modelling is an important aspect of water resources and environmental science for understanding the behaviour of the hydrological cycle and developing sustainable water management strategies.
Catchment modelling allows the simulation of water flow, precipitation, runoff patterns and the transport of sediment and pollutants within the catchment. This is often done using hydrological models based on computer simulations. These models help to analyse different scenarios and environmental impacts, such as those associated with land use change, climate change or human activities.
The benefits of catchment modelling are many. They include predicting floods, assessing water quality, planning water management measures, identifying potential environmental impacts and developing strategies for sustainable water use. Understanding the dynamics of catchments is crucial to preventing water scarcity, protecting ecosystems and reconciling human activities with the environment.
What we will do in this unit
We will investigate to what extent the terrain model and the chosen algorithm influence the accuracy and relevance of hydrological forecasts when modelling the Lahn catchment area.
Learning Objectives
After this tutorial you will be able to
- Identify and evaluate appropriate tools and workflows
- Identify basic technical concepts
- Evaluate different technical workflows in relation to a problem
- critically reflect on and document which decisions led to which process
Materials Required
Data
- CGIAR-CSI SRTM V4 The CGIAR-CSI SRTM V4 is probably the best homogeneously post-processed SRTM dataset in the world. Regarding the new version 4, CGIAR-CSI says: “envisages that CGIAR-CSI SRTM version 4 is our definitive and final release […]”, see CGIAR FAQ.
- SRTM Terrain Model TileDownloader.
ATTENTION:
(Requires registration with NASA Earthdata) The Infolink of the surface is corrupted, see the NASA JPL page for the necessary metadata.ATTENTION:
This file must be downloaded as a ZIP file, as it is in SRTMHGT format. - OpenDEM Germany
ATTENTION:
Please be sure to read the Info page as extensive re-analysis of the SRTM data has taken place. - OpenDEM Europe
ATTENTION:
Please be sure to read the Info page as an extensive re-analysis of the SRTM data has taken place. - GIS&T Body of Knowledge Watershed Concept
- Watershed ArcGIS Story
- White-box QGIS Tuitorial
- Saga/QGIS Tutorial
- Saga Tutorial
- QGIS Tutorial Hydrolocical Analysis
## Tasks 3 Please choose one or more approaches to model the catchment of the river Lahn with the outflow point Lahnstein. Compare with the linked online version of mghydro.com