Hydrological data and modelling
Soil and Water Assessment Tool (SWAT) datasets
Water Resource Commission project C2019-2020-00089: A South African national input database to run the SWAT model in a GIS
This ongoing study led by Dr Jay le Roux at the University of the Free State will collate multiple geo-spatial datasets at a national scale and interpret/format the data for use as baseline input to run the ArcSWAT model for any catchment in SA.
The hydrologically improved DEM was created from the SRTM 90 x 90 m DEM (Weepener et al., 2012). The extent of the 90 m Improved DEM includes areas in bordering countries for catchments such as the Orange, Molopo and Limpopo Rivers.
The 30 x 30 m DEM for South Africa was created from the Shuttle Radar Topography Mission (SRTM) 30 x 30 m DEM. The DEM has not yet been hydrologically improved.
This following maps are available in the WRO:
South African National Land-Cover (SANLC) 2013
South African National Land-Cover (SANLC) 2018
South African National Land-Cover (SANLC) 2020
This map and attribute table was prepared from the Land Type Database of SA and is currently undergoing testing in WRC Project C2019-2020-00089.
> Other SWAT tools:
SWAT-LUT (a standalone user-friendly graphical interface for updating land use in SWAT)
Primary catchment boundaries and rivers overlayed onto the 90 m Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) (Weepener et al., 2012).
HAMSA (under development)
One important aim of the WRO is to have a ‘plug-and-play’ functionality for the Soil and Water Assessment Tool (SWAT) to facilitate hydrological modelling in South Africa. This will be achieved through the application of SWAT within the proposed HydrologicAl Model for South Africa (HAMSA) on-line platform. It is based on HAWQS, a web-based interactive water quantity and water quality modelling system that was developed for the United States. HAWQS substantially enhances the usability of SWAT to simulate the effects of management practices based on an extensive array of crops, soils, natural vegetation types, land uses, and other scenarios for hydrology, as well as for water quality parameters such as sediment, pathogens, nutrients, biological oxygen demand, dissolved oxygen, pesticides, and water temperature.
For hydrological modelling questions see the Stack Exchange Earth Science site (https://earthscience.stackexchange.com/), create a user profile, and start asking and answering hydrological modelling questions. More information is available here.
Global soil moisture data - European Space Agency (ESA) Climate Change Initiative
ARC Soil, Climate and Water - Land Type Maps and Memoirs (catalogue) (pdf)
Water Observation and Information System (WOIS) (Africa) (ESA Tiger initiative)
World Resources Institute - Aqueduct (tools to identify and evaluate water risks)