national water accounting: setting the limits of consumptive water use in the agricultural sector,...
TRANSCRIPT
Wim Bastiaanssen
National Water Accounting: Setting the
Limits of Consumptive Water Use in the
Agricultural Sector
Competing water users at river basin scale
October 27,
2015
3
Distinguish green & blue water
Today
Objectives WA+
Operationalize a standard reporting system on water resources conditions in river basins, including hydrology, water management, land use and the services from consumptive use based on open access data sources, and with a standard terminology. Both current and future conditions can be assessed
sheets tables maps
On paper, we can measure everything...
Data sources will never be complete and made fully
accessible, especially when competition on water
resources increases
Ideal
data
Real
data
WA+ is mainly based on accessible satellite data E
ye in
the s
ky
Six key data sets from remote sensing
•Digital Elevation Model
•Land use
•Precipitation
•Evapotranspiration
•Net radiation
•Biomass production
In near future:
•Water levels
•Groundwater changes
IASA – IFPRI Global Cropland Map
October 27,
2015
15
October 27, 2015 source: MEWINA
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October 27, 2015 source: MEWINA 17
Consumptive use Egypt
Landsat
30 m
ET by agricultural land use
Egypt Lybia Mauritania ET ET ET
(mm/yr) (mm/yr) (mm/yr)
Post-flooding or irrigated croplands (or aquatic) 932,9 694,3 na
Rainfed croplands 369,3 523,5 661,1
Mosaic cropland (50-70%) / vegetation (grassland/shrubland/forest) (20-50%) 610,5 700,6 637,3
Mosaic vegetation (grassland/shrubland/forest) (50-70%) / cropland (20-50%) 393,3 333,1 360,4
Green water consumption (from rainfall)
October 27, 2015 source: MEWINA
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Blue water consumption (from irrigation)
October 27, 2015 source: MEWINA
21
Blue water consumption
October 27, 2015 Source; MEWINA
22
Water Availability (dry & wet years)
Utilized flow Utilizable flow
Water consumption Actual crop ET
Polluted water
Water in products
(Water supply) Irrigation supply
Utilities Inundations
Crop water stress
Water scarcity
Water demand Irrigation (potential crop ET)
Industries Domestic
Environment
Water allocation
Proper Accounting
Atmospheric moisture recycling is significant
Conclusions
• We can technically start preparing monthly water accounts for the entire NENA region
• The data will be posted on a repository and available for all planners in the agricultural water use sector
• This enables national agricultural policy planning, including maximum sustainable withdrawals and consumption
• A monitoring program can be established
• The required data can be taken from new remote sensing projects
• Learn lesssons from other arid climate countries
Thank you !
www.wateraccounting.org