WaterBase

Free, Open Source Software for Integrated Water Resources Management

Chris George and Luis Leon

WaterBase

• Drought• Flood• Pollution• Water-borne disease• Sediment• Water quality• …

It’s not just for drinking …

Litres of water needed to make:• 1 litre of petrol 2.5• 1 litre of biofuel 1000• 1 cotton T-shirt 2700• 1 kilo of wheat 4000• 1 kilo of beef 16000

Wealthier people “consume” 3000 litres per day

WaterBase

• Water management is critical• Must be at basin level• Based on public/private partnership• Requires

– Expertise– Information– Modelling + Decision support– Community involvement

Modelling River Basins

• Terrain (shape of the land)• Soil• Landuse (vegetation)• Climate (rainfall, temperature, humidity, …)• Model – a computer program that can

simulate the natural processes involved• Expertise

Resources: Available WWW Data DEM = 90m SRTM (srtm.csi.cgiar.org)

Shuttle Radar Topographic Mission World wide coverage (V3 pit filled)

Tile download

Direct FTP Download

Resources: Available WWW Data Land = GLCF (glcf.umiacs.umd.edu)

Global Land Cover Classification Satellite raster (1km resolution)

Resources: Available WWW Data Soil = FAO/UNESCO (www.fao.org)

Digital Soil Map of the World 1:5 000 000 (raster 5x5 arc-minute)

• Readily available input • Physically based• Computer efficient• Comprehensive – Process Interactions• Simulate Management

Model Philosophy

• Weather• Hydrology• Sedimentation• Plant Growth• Nutrient Cycling• Pesticide Dynamics• Management• Bacteria

Upland Processes

Management

• Crop Rotations• Removal of Biomass as Harvest/ Conversion of

Biomass to Residue• Tillage / Biomixing of Soil• Fertilizer Applications• Grazing• Pesticide Applications• Irrigation• Subsurface (Tile) Drainage• Water Impoundment (e.g. Rice)

Management

• Urban Areas– Pervious/Impervious Areas– Street Sweeping– Lawn Chemicals

• Edge of Field Buffers

WaterBase

• Support for Integrated Water Resources Management

• Using free, open source software

• An international network of users and developers

Why Open Source?

• Free• Secure: no supplier dependence• Encourages involvement and sense of

ownership; internationalization• Support network via internet• High quality• Good maintenance• Open standards; interoperability• Examples: Linux; Apache; GRASS; …

WaterBase

Three phases:

1. First tool available: MWSWAT

2. Network of partners (current)

3. Seek funding for development of– Tools– Training materials and technical

documentation on the internet– Data repository design and implementation

First tool: MWSWAT

• Based on MapWindow GIS system http://www.mapwindow.com

• Uses SWAT (Soil and Water Assessment Tool) http://www.brc.tamus.edu/swat

• Distribution: internet and DVD

Preparation for SWAT

1. Start with a DEM, a Digital Elevation Map (a grid, or 2-D array, of heights).

This DEM has some 3.4 million values, 83.3m apart.

Preparation for SWAT

2. Calculate stream reaches. (Uses David Tarboton’s Taudem software.).

Preparation for SWAT

3. Mark outlet(s) and calculate sub-basins

Preparation for SWAT

4. Add landuse map (another grid). Here resolution roughly 10 times DEM’s.

Preparation for SWAT

5. Add soil map (another grid). Here resolution roughly 80 times DEM’s.

Preparation for SWAT

6. Calculate HRUs: Hydrological Response Units: unique combinations of sub-basin, landuse, soil and slope. Small ones omitted using thresholds. (Here 79 retained from 326.)

Preparation for SWAT

7. Add weather data from weather stations (can be automatic) and weather generator.

8. Set start and end dates, and some SWAT parameters.

9. Write SWAT input files (here 620) and database tables.

10. (Optionally) edit SWAT input files and tables.

11. Run SWAT.

12. Examine SWAT outputs.

SWAT Outputs

• Runs typically over several years• Inputs and outputs (daily/monthly/yearly) per

subbasin– Water flow– Sediments– Nutrients– etc

Model Output

Output:- Extract from reach output- Outlet at any sub-basin (swat2dat utility)- Import (i.e. spreadsheet) & plot

Reach file

output.rch

Scenarios

• Typical use will be “what if we change …”– Temperatures– Rainfall patterns– Water management (reservoirs; sewage treatment;

…)– Landuse (urban development; plant trees; cultivate

new areas; …)– Crop management (crop type; tillage practices; …)

• Identify hotspots

• Thanks to...– David Lam & David Swayne (NWRI & UG)– Daniel Ames, Chris Michaelis, & Allen Anselmo

(MapWindow Team)– Raghavan Srinivasan (SWAT)– Gary Bowen (TRCA)– Karim Abbaspour (EAWAG)– Dagny Janowska (BIAD)

Join us!

http://www.waterbase.org

waterbase.contact@waterbase.org