Growing Enough Food Without Enough Water

1. Growing Enough FoodWithout Enough Water David Molden

2. About IWMI IWMI is one of 15 research centers supported by the Consultative Group on International Agricultural Research (CGIAR). Mission: To improve the management of land and water resources for food, livelihoods and the environment. Where we work: Headquarters: Colombo, Sri Lanka InAfrica : Ghana, Southern Africa, Ethiopia InAsia: India, Pakistan, Nepal, Laos, Vietnam, Central Asia, Syria

3. Water Scarcity 2000 1/3 of the world’s population live in basins that have to deal with water scarcity

4. Other Water Pressures Population & Diet– food grain production projected to increase by 100% by 2050 Urbanization - Cities are projected to use 150% more water in 2025, encroach on ag land Energy – Hydropower and biofuels compete for water and land Climate Change – Shifting patterns of water availability Drivers of Land & Water Use

5. Limits – Reached or Breached Land degradation –limits productivity River basins closed – Colorado, Murray Darling, Yellow, Indus, Amu Darya ……… no additional water left Groundwater overdraft – in agricultural breadbaskets Fisheries– ocean and freshwater at a limit, aquaculture will become more prevalent Livestock – limit on extent of grazing land, more will come from mixed and industrialized production

6. Some areas will be wetter, others drier, more rainfall variability, all hotter Source: Arnell, 2003 – IWMI, FAO, ADB report on revitalizing irrigation.

7. Water Scarcity and Climate Change Some areas wetter, some areas drier

8. Will there be enough water?

9. One liter of water produces one calorie on average One liter of water produces one calorie on average Food Supply in Calories

10. Per capita meat demand (kg/cap/yr) 140 data projections 120 100 USA 80 Meat consumption kg/cap/yr 60 China 40 World 20 India 1961 2003 2050 More meat and milk requires more feed grain, requiring more water

11. Will there be enough water? More People – 6.5 to 9 billion people by 2050 More people – 6.5 to 9 billion people by 2050 More calories & more meat, fish, milk More food production – need to double grain production by 2050 More water for food – if practices don’t change, water needs for agriculture will double Something has to change More calories & more meat, fish, milk More food production – need to double grain production by 2050 More water for food – if practices don’t change, double water needs This equation doesn’t work – something has to change

12. Water Management Solutions Olivia Molden

13. Major Pathways to Meet Future Food & Water Demands • Improve water productivity (more food/water) • Irrigation systems • Rainfed systems • Expand irrigated & rainfed agriculture • Promote trade from highly productive to less productive regions • Manage demand, consume and waste less

14. Grow more food per unit of water

15. Productivity of Water at 40 Irrigation Systems: There is ample scope for improvement. Source: Sakthivadivel et al, 1999

16. Range of water productivities in biological, economical and nutritional terms for selected commodities aIncludes extensive systems without additional nutritional inputs to superintensive systems Source: Muir, 1993; Verdegem, Bosma, and Vereth 2006; Renault and Wallender 2000; Oweis and Hachum 2003; Zwart and Bastiannsen 2004

17. WP for Livestock and Fish • Beef 0.03 to 0.1 kg/m3 (ET) • Fish 0.05 to 1.0 kg/m3 (ET) Rapid increase in consumption of fish, meat, milk, with income Huge scope for improvement – feed source, and animal husbandry important

18. Reasons for Caution

19. Often problem is overuse, not low efficiencyLow water productivity is the real waste 90% 740km3 Accounting for Water Use at Chistian, Pakistan

20. Breeding: optimism or caution? • Biophysical limit on biomass/transpiration • Harvest index already maximized – limit on marketable produce per unit transpiration • Hard to foresee a big jump • except in underutilized, understudied crops But helpful in reducing damage from weeds, insects, minimizing impacts of drought

21. Water productivity rises faster at lower yields and levels off at higher yields Source: Adapted from Zwart and Bastiaanssen 2004 In Water for Food, Water for Life, Earthscan Publishing

22. Water productivity is subject to diminishing returns Area of Greatest Potential Areas with high poverty Source: Based on the yield-water productivity relationship for rainfed cereals in Rockström (2003) In Water for Food, Water for Life, Earthscan Publishing

23. Opportunities in Rainfed Agriculture • Largest opportunities to build resilience and improve water productivity are in rainfed landscapes – low productivity, high poverty • Technology • water harvesting, supplemental irrigation • Field water conservation to reduce nonproductive evaporation • Improved nutrients • Drought resistance varieties • Expand “water” to includepolicies and practices forupgrading rainfedsystems

24. Irrigation potential developed: Egypt, Morocco, Somalia, South Africa > 75% Botswana, Sudan, Zimbabwe, Madagascar, Mali, Malawi, Uganda 50-75% Rest < 50%

25. Irrigated A green-blue view Rain = 1745 km3 Rainfed ET – 190 km3 Irrigated ET – 67 km3 Outflow – 10 to 30 km3 Limited options to expand irrigation – but gets attention Ample options to upgrade agriculture on rainfed lands – gets little attention Pastoral Rainfed Wetlands

26. Consider A Range of Agricultural Water Management Options Fish, Livestock, Crops, Ecosystem Services

27. Transforming Agricultural Water Management We know what to do – we need to know HOW?

28. Shallow Groundwater Irrigation • Use of wells and dug-outs • Small-scale: labour-intensive manual irrigation • Few commercial farmers : motor pumps • Irrigation during dry season • Crops: Mainly tomato, pepper, local vegetables

29. Motorized pumps: extreme demand – extreme opportunity for change Solutions • Affordable & efficient pump for smallholders • Alternative energy sources (solar) • Ban import tax on ag equipment (cost of pump <$100 in India, $140 in Togo, $300 in Ghana). Zambia recently abolished • Extension training But: • Small pumps are inefficient (50%) • Still quite expensive sales price and running • Technical knowledge gap • 6% GHG emission in India • Resource sustainability • No women ownership? • Millions of pumps in operation in S-Asia • In India >70% of irrigated production • High demand in SSA • Spontaneous uptake • Privately owned • Enormous impact on farmer & landless income Easy to transport: * individual * scattered plots * rent-out

30. Accra Market Queen

31. Making it Happen – beyond technologies • Access to technology, seeds, fertilizers? • Is there enough money or credit to buy them? • Are markets available to sell? • Financially viable? • Water and land resources available? • Is it sustainable – financial, ecological? • Supportive policies? • “Mind mobilization” MatsepoKhumbane

32. Summary – Water, Food & Livelihood Agenda • Enhance & safeguard water access for the poor • Increase water productivity • In doing so enhance ecosystem services & resilience • Transform water governance and management

33. Water access, productivity,and ecosystems for livelihoods • Upgrade rainfed areas – manage water & soils • Revitalize irrigation • Sustainable groundwater management • Reuse wastewater safely • Transform water governance and management • Support with information systems