Post on 16-Jan-2015
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Water for a food-secure world
MANAGING WATER RESOURCES VARIABILITY FOR IMPROVED FOOD SECURITY AND LIVELIHOODS
VLADIMIR SMAKHTIN
Contributors: Giriraj Amarnath, Nishadi Eriyagama, Matthew McCartney, Paul Pavelic, Upamali Surangika
International Water Management Institute (IWMI)
CCAFS-WLE- IWMI Science Seminar, University of Copenhagen, 4 October 2013
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Water for a food-secure world
…TOO MUCHTOO LITTLE…
EVERYTHING IS VARIABLE, WATER - TOO
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Water for a food-secure world
WATER VARIABILITY INCREASES WATER SCARCITY
Source: Smakhtin and Schipper, 2008
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Water for a food-secure world
Source: Brown and Lal (2006)
WATER VARIABILITY INFLUENCES ECONOMIC DEVELOPMENT
A climate with moderate annual rainfall and its low variability favors prosperity
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Water for a food-secure world
WATER VARIABILITY MANIFESTS ITSELF IN DROUGHT AND FLOOD DAMAGES
Source -EM-DAT: The OFDA/CRED International Disaster Database, Brussels
Average annual characteristics over 1980-2008
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Water for a food-secure world
IN MANY REGIONS OF THE WORLD, WATER RESOURCES VARIABILITY IS PROJECTED TO INCREASE WITH CLIMATE CHANGE
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Water for a food-secure world
VARIABILITY MANAGEMENT MUST RECEIVE MUCH MORE SCIENCE, POLICY AND INVESTMENT ATTENTION
• Better quantification of variability hot spots, risks and extent
• Re-thinking water storage
• Conjunctive management of floods and droughts in river basins through subsurface solutions (vs just surface ones)
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Water for a food-secure world
AGRICULTURE; PAGE (2005)
POPULATIONCIESIN - 2010
FLOOD EXPOSED GDPWB, 2010
IDENTIFY AND QUANTIFY HOT SPOTS
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Water for a food-secure world
QUANTIFY RISK AND EXTENT
2010
8-days maps of inundation extentGanges Basin
Source: Amarnath et al, 2012
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Water for a food-secure world
LACK OF WATER STORAGE ≈ FOOD INSECURITY
Source: World Bank, 2006
Ethiopia
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Water for a food-secure world
PROMOTE THE IDEA OF “WATER STORAGE CONTINUUM”Source: McCartney and Smakhtin 2010
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Water for a food-secure world
BETTER PLAN WATER STORAGE DEVELOPMENT
A need for water storage for livestock
Source: Eriyagama et al. 2009
Proportion of water deficit in “mean” drought that can be satisfied by existing large dams’ storage
Source: McCartney et al, 2013
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Water for a food-secure world
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENT
Current Climate – Dry Season
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Water for a food-secure world
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENT
Current Climate – Wet Season
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Water for a food-secure world
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENT
Future Climate - Wet Season
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Water for a food-secure world
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENT
Underground Taming of Floods for Irrigation (UTF-I);
Wet season
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Water for a food-secure world
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENT
Underground Taming of Floods for Irrigation (UTF-I);
Dry season
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENT UTF-I desktop case study: Chao Phraya basin, Thailand
(Source: Pavelic et al, 2012)
Land Use UTFI in plan viewAlluvium aquifers
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Water for a food-secure world
CONJUNCTIVE FLOOD AND DROUGHT MANAGEMENTUTF-I desktop case study: Chao Phraya basin, Thailand
(Source: Pavelic et al, 2012)
• Harvest water only in very wet years - approximately 1 year in 4 • Around 200 km2 land dedicated to flood harvesting may be needed (< 1% of the total
basin area)
• Additional 65,000- 270,000 ha of irrigation possible
• $150 mill / year - mean income to smallholder farmers
• Cost of implementation < $ 1 Bill. Payback time can be 7 -14 years, depending on the efficiency of the scheme
• Farmers’ participation is critical
• No analogs so far exist
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Water for a food-secure world
KEEPING VARIABILITY ?
• Variability has positive effects too, e.g. the range of high and low flows, their proper timing and frequency is needed to ensure a healthy river
• The challenge is to alleviate negative aspects of variability, while maintaining its positive side
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Water for a food-secure world21
THANK YOU !
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Water for a food-secure world
GANGES WATER MACHINE AND UTFI
• Suitability for UTFI: – Prefeasibility analysis first – 12 indicator groups of suitability next – Potentially suitable are of 433,367 km2, where suitability is categorised from
“low” to “very high”