The HydrologicAl Model for South Africa (HAMSA) is currently being developed as part of the Water Research Observatory project. It is based on the HAWQS system developed by Texas A&M who are also providing technical support to HAMSA. It's core modelling engine is SWAT, and it allows users to upload, share and run simulations in the cloud. Various scenarios can be set up and tested using a user-friendly interface, and the output can be visually compared between two scenarios. 

South African SWAT modellers are encouraged to upload and share their SWAT projects that were produced in ArcSWAT and QSWAT, with the final aim of being able to simulate any catchment in South Africa, including the water quality constituents sediment, pathogens, nutrients, biological oxygen demand, dissolved oxygen and pesticides, as well as water temperature. 

Setting up an ArcSWAT or QSWAT project

Creating a SWAT project has become easier than ever before thanks to a recently completed WRC project to provide expertly formatted DEM, land cover and soil information for the whole of South Africa.  These layers can be downloaded from the WRO's data platform.

Make sure all the layers have a common project in ArcMAP or QGIS. If not re-project the layers. We recommend WGS_1984_Albers and it can be checked by clicking on the layer >> righting clicking on Properties and under the Source tab check that Standard_Parallel_1 and Standard_Parallel_2 have the same value for all layers. 

It is important to keep saving your SWAT project as you progress. 

For the soil, you will need to copy the usersoil.mdb usersoil data into the SWAT2012.mdb database for the project you are setting up. See this tutorial for more information.


Importing ArcSWAT and QSWAT projects into HAMSA - Frequently Asked Questions 

Q: When I try to import a project, I get a message that the it doesn't contain weather data. But I'm sure I have included my weather input files.

A: For the weather files, you need the ones that are written when you run SWAT. Not the ones you give to SWATeditor/ArcSWAT to import. So when you write inputs/run the model and it puts files in Scenarios/Default/TxtInOut, you want to grab the pcp1.pcp, tmp1.tmp from there (rename if necessary, but be sure they don’t have .txt extension).

Q: My project runs but my catchments do not show on the map?

A: Make sure that your GeoJSON files are saved with the correct co-ordinate system (WGS 84 for CRS).