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Sustaining Groundwater Irrigation Economies:

Sustaining Groundwater Irrigation Economies:. China’s Challenge and Global Experience. Explosive Growth in Groundwater Use. Powerful manifestation of growing water scarcity; Meteoric growth after 1960

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Sustaining Groundwater Irrigation Economies:

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  1. Sustaining Groundwater Irrigation Economies: China’s Challenge and Global Experience

  2. Explosive Growth in Groundwater Use • Powerful manifestation of growing water scarcity; • Meteoric growth after 1960 • Of the 1000 km3 /year of global groundwater use, over 800 km3 in agriculture; 600 in South Asia and North China; • Of the 300 m ha of global irrigation, over 1/3rd is from groundwater wells. • Protecting groundwater is critical for future supply of domestic water needs.

  3. Four Groundwater Socio-Ecologies (GwSEs) Danger zone

  4. Growth in Population Density around the world (people/km2) , 1700 – 1990 Contrary to popular notion, population growth over past 300 years occurred in semi-arid areas.. Source: International Institute of Applied Systems Analysis (IIASA)

  5. Expanding Cropland 1700-1990 Fraction of grid cell in croplands Because surface irrigation occurs in river valleys, we often think that gw irrigation too would concentrate in regions of abundant recharge.. Source: International Institute of Applied Systems Analysis (IIASA)

  6. GW intensification has had little to do with resource Endowments; but with Population pressure.. Long-term average groundwater recharge Malthus Versus Boserup Source: Döll, P., Lehner, B., Kaspar, F. (2002): Global modeling of groundwater recharge. In Schmitz, G.H. (ed.): Proceedings of Third International Conference on Water Resources and the Environment Research, Technical University of Dresden, Germany, ISBN 3-934253-17-2, Vol. I, 27-31

  7. North China farmers have drastically increased their groundwater use

  8. According to FAO, gw irrigated area in India, China, Pakistan, B’desh and Nepal together is larger than anywhere else in the world...

  9. In sum, groundwater boom in Asia is driven by: • Tubewell technology • High population pressure on land; • Semi-arid, monsoon climate • Green Revolution technology • Pump and tubewell technology • Failure of public irrigation systems • Electricity subsidies (in India, Mexico, Syria)

  10. Groundwater irrigation drives national and regional politics because it affects majority of country’s population..

  11. Beneficial impacts: • Biggest alleviator of rural poverty • Driver of agricultural productivity growth • Spatial equity in access to irrigation • High water productivity • Socio-economic and political stability • Mobilizes private capital

  12. Negative Impacts. • Groundwater depletion; • Increased pumping costs and energy use; • Drying up of lean season stream-flows and wetlands; • Threat of Secondary salinization • Geo-genic contaminants: arsenic and fluoride;

  13. Informalization of Irrigation.. • In well-managed water economies, water users are mediated through formal water service providers; and self-supply is minimal. • The groundwater boom has made some of Asia’s water economies highly informal. Most water users have little or no contact with public systems; so they are difficult to reach and regulate..

  14. Reigning in the booming groundwater economy.. China’s new policy of ‘water withdrawal permits’ is designed to formalize groundwater irrigation economy..

  15. Water saving technologies—drips and mulching-- are taking off in cotton and other crops.. To what extent will these ease aggregate pressure on China’s groundwater aquifers unclear.. Some argue only reducing irrigated areas will help.. But this will be difficult in the short run.

  16. IWMI Assessment of Mexican Water Reforms • ‘Concessions’: Water Rights and volumes assigned ; Tradable; COTAS • Mexico has around 100,000 irrigation tubewells; despite that, monitoring concessions and penalizing violations has proved difficult; • Doubtful if reforms have contained groundwater extraction • Mexico is now turning to differential energy prices as a mechanism to penalize over-drafters.

  17. Challenge of groundwater governance.. • Banning private wells would be difficult to implement; crowd them out by improving public water supply • Regulating final users is difficult; facilitate mediating agencies to emerge, and regulate them. China has lessons to offer. • Pricing agricultural groundwater use is infeasible; instead, use energy pricing and supply to manage agricultural groundwater draft. • No alternative to improved supply side management: better rain-water capture and recharge, imported surface water in lieu of groundwater pumping. • Grow the economy, take pressure off land, formalize the water sector.

  18. Transformation of Informal Water Economies with Overall Economic Growth

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