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Thierry Facon, RAP-NRE and Chen Zhijun, TCIO Workshop on Water Resources Demand Management Learning Forum for Irrigation 26-28 July 2011 JW Marriott Hotel, Bangkok, Thailand Demand Management for Irrigation: Revisiting some Basics
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Plan ► Generalities of demand management for irrigation ► Some difficulties ► Some recent approaches ► Conclusion
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Plan ► Generalities of demand management for irrigation ► Some difficulties ► Some recent approaches ► Conclusion
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Major options and domains
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Coping with water scarcity: a dynamic model
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Supply augmentation options
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Demand management options
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Dynamics of agricultural response
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Different options over time
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Classical options
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Plan ► Generalities of demand management for irrigation ► Some difficulties ► Some recent approaches ► Conclusion
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InformalFormal Self-supply predominatesService providers dominate Vast numbers of tiny, primary water diverters from nature Very few, but large primary diverters of water from rivers, lakes Water institutions: local, fragmented, informal Water institutions: few, formal, legal bodies Intermediation in water services low or absent Very high degree of intermediation in water provision Even if water is scarce its free…Even if water is plentiful, it costs money… Informal and formal natures of water economies Source: Tushaar Shah Socio-economic development, IWRM Planned adaptation Irresponsive institutions Autonomous adaptation Planned adaptation Mitigation Formalize land use planning/management to formalize ET Mgt Governance-based Policy, incentives Lateral approaches
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Multiple uses and services ► Multiple Uses in Large Irrigation Systems is the norm ► CROPS = often a fraction of water inputs (<50%) 14 Water Share: water balance Value Share : Economical analysis (Value, jobs, ecosystems?) Services identification & remuneration Constraints and opportunities of management Governance of the MUSF System
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Uncertainty on basic performance indicators
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Confusion: Improving productivity or efficiency? “As irrigation is inefficient (30/40/50% of the water diverted reaches the plant), we can reduce the waste and losses and reallocate this to other users by increasing irrigation efficiency” “As irrigation is inefficient (30/40/50% of the water diverted reaches the plant), we can reduce the waste and losses and reallocate this to other users by increasing irrigation efficiency” Physical water scarcity ► Basin closure ► What is recoverable is mostly recovered
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Irrigation efficiency ► Confusion between field, system efficiency and basin efficiency is common and inexcusable but underpins many policies and investments ► But field efficiency and more efficient technologies can be very good for: energy water quality sometimes in-stream flow reducing drainage money labour, etc.
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“Fractions” Terminology for Water Accounting Water Use Water Use Consumed Fraction ► Beneficial Consumption ► Non-beneficial Consumption Non-Consumed Fraction ► Recoverable flows ► Non-recoverable flows
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Water scarcity is often constructed by planning: The planning/closure spiral: 1. develop a dam with an irrigation system that can only irrigate a portion of the command area in the dry season 2. create water scarcity which justifies building an other dam 3. Which comes with its own command area upstream, and will absorb and water you try to send down 4. Back to step 2 IWRM: any water you want to send down for environmental flows, water quality or salinity control will be absorbed on the way IWRM: any water you want to send down for environmental flows, water quality or salinity control will be absorbed on the way ► Many irrigation agencies still function this way ► Vested interests
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River basin closure processes / construction of water scarcity ► river basin trajectories and their drivers ► Over-building of river basins ► Over-allocation of entitlements ► overdraft of reservoirs and aquifers ► double squeeze of agricultural water use, due to declining water availability and quality and rising urban and environmental needs
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Wuhan University/ Yuanlai CUI : Relativity of Water saving irrigation: the scale effect. The adapted methods of WSI is different under different water resources conditions, natural conditions and social economical development conditions; The standard of WSI also different under different countries, regions, and developing stages. WSI is relativity. Rehabilitation Cropping pattern change Water pricing AWD spreading Reuse of drain and rainfall
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Relativity of WSI Water balance and recycling in rice irrigated area (scale effect) WSI is relative in spatial scale. Field, irrigation system, basin, the “loss” and WSI way is different
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Traditional IE: canal water use effi., field water use effi. and irrigation effi. These indicators are helpful for planning, design and management of irrigation projects. From Qnet to Qgross However, these indicators ignore the reuse of return water, losses from irrigation water supply system are regarded as losses of the irrigation system TIE are not suitable for WS potential evaluation. Traditional IE indicator
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Depleted fraction. Ratio of total depletion or ET to Gross or available Process depleted fraction. Ratio of process depletion to irrigation Benefit depleted fraction. Ratio of ET to total depletion or Gross or available Water productivity New evaluation indicators
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Drainage fraction. Drainage fraction to gross inflow or available water There are mainly other new indicators which are suitable for WSP evaluation under diff. scales, but this indicators are normally not easy to calculated, such as ET, drainage etc
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Case study Command area 43 km2 (3% of area ZIS ) Six closed scales were selected for water balance and TN losses analysis
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WP under different scales (2009) Case study WP I increased 64% from field to small watershed scale
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Drainage fraction under different scales (2009) Figure 3 shows that the water saving potential of field scale was 33%, the potential of middle scale ranged from 16% to 28% and the potential of small watershed scale was 21%. It presented the scale effect of water saving potential at different scales. The TIE of ZIS in only 43%, means 57% WS potential, that is not true Case study DF decreased from field to small watershed scale
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Questions What is the proper indicator which considers the reuse of return flow but is easy to estimate? Traditional IE Real IE ZIS IE and WS potential when lining canal water resources utilization rate=ratio of ET to gross inflow Return rate of irrigation = ratio of return flow to irrigation WS potential (M m3) Trad. IE43.9%36.1 Real IE66.2%10.0 28% of TIE underestimate overestimate
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Things are complicated ► Some water can be saved but not as much as is claimed ► There are no silver bullets on the horizon on the productivity or irrigation technology side ► When agricultural water management is already moderately good, things tend to a zero sum game ► Increasing efficiency, more efficient technologies, water rights and water pricing often lead to increased water consumption (ET) ► Problems are becoming wicked ► In many basins agriculture will need to shrink to achieve water savings
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Francois Molle Water pricing : a "good idea" with limited potential in large scale gravity schemes 1. Is water scarce ? 2. Are losses really lost? 3. Are "savings" used ? 4. Are losses at the farm level? 5.Is demand elastic ? 6. Is pricing volumetric? 7. Is supply on-demand ?
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Full supply, continuous flow, with occasional short chaotic phases; No data collection (or only at headworks); problems solved by sending more water. Chaotic supply; land fallow; conjunctive use ubiquitous Rotations are the rule; some fallow land in the dry season; wells and pumps widespread; serious head-end/tail- end problems Full supply, with temporary or permanent rotations, head-end/tail- end problems increase; supply sometimes uncertain. Data loosely collected, often faulty, and rarely analyzed. W1WoD0D1 RWS 1 Volumetric management, secondary or tertiary canal bulk allocation; or individual quota systems; intensive data collection and analysis Reactive management Volumetric management Water pricing > conservation > conditions
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Groundwater irrigation W1 W0 D0/D1Bulk (S/T) Q O % of Irrigated area Type of scheme management No effect Possible effect of pricing Potential effect Effect at the margin
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W1 W0 D0/D1Bulk (S/T) Q O % of Irrigated area Type of scheme management Possible effect of pricing Effective impact Desirable evolution: improving management
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Water pricing > cost-recovery > in practice 1.Volumetric pricing and conditions of elastic demand are extremely rare; pricing will not, in most cases, influence water use; high prices may have influence but at the cost of farmer income. 2.Even in on-demand systems, prices are not used to regulate demand: scarcity is managed through quotas; prices used at the margin only. 3.Improved management towards ‘volumetric management’ is needed; it is foremost a management issue 4.Once management is improved and scheme modernized, there is less scope for water savings (and role for pricing) 5.Can scarcity coexist with wastage? A management issue. FTO no TAP 6.“Pricing is needed to signal the value of water”: applies to urban supply; in irrigation, scarcity is obvious and pricing creates a sense of right 7.Prices would have to be raised much above O&M and to a significant % of income to find elasticity: will this be acceptable? Water pricing > conservation > conclusions
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use where
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Plan ► Generalities of demand management for irrigation ► Some difficulties ► Some recent approaches ► Conclusion
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Developing sound integrated water conservation strategies Using sound water accounting concepts to develop and monitor integrated water conservation strategies in China Using sound water accounting concepts to develop and monitor integrated water conservation strategies in China THE PRACTICETHE RESULTS it is not sufficient to control abstractions and promote “irrigation water use efficiency” restoring a sustainable groundwater regime ultimately depends on reducing water depletion (i.e. reducing evapo- transpiration (ET) by crops) ET reduction and improved water productivity/ET explicit objectives and operational targets improved infrastructure and operation to improve productivity and incomes institutions, allocation mechanisms and supporting information management systems a water supply organization and water users associations KEY POINTS A sound water accounting basis: a necessity for critical groundwater systems, areas with significant conjunctive use, closing river basins and systems with high return flows (deltas, rice systems).
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Expanding capacity and knowledge Farmers manage their groundwater resources in Andhra Pradesh Farmers manage their groundwater resources in Andhra Pradesh THE PRACTICETHE RESULTS 60%+ irrigation water requirement met by GW. hydrocratic measures fail to address over-abstration Farmers learn about GW and become the GW organizers, planners, and advocates Farmers learn about ways to improve productivity of water used 1700 farmer facilitators, 33% women Outreach: 1 million farmers 42% units have reduced abstraction permanently and 51% intermittently Results have combined environmental sustainability and poverty reduction The only successful project of community GW management at global level KEY POINTS Farmers realize that GW conservation through collective decisions is a safeguard of their own interest Demystify science A promising approach to manage atomistic irrigation A collective of NGOs, academic and civic leaders
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ANDHRA PRADESH RURAL LIVELIHOODS PROGRAMME WATER AUDIT ► Inflows to many tanks have declined in recent years, with a severe impact on the utility (inc. recharge), biodiversity and cultural value of the tanks and on reliability of domestic water supplies. ► Communities’ belief: i)Decline in rainfall ii)Deforestation in the tank catchment area Water audit Water harvesting created upstream along drainage lines in the tank catchment areas in recent years. Recharge captured locally and small contribution to base flow captured by downstream structures.
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1) water-related participatory assessments that produce outputs suitable for GIS analysis; 2) water auditing that combines terrestrial and remotely- sensed data; 3) modeling for assessing the impact of water harvesting structures on downstream water resource availability; 4) decision trees that use social, and institutional information along with physical information for targeting project interventions and activities; 5) a simple GIS-based participatory assessment methodology for M&E of rural water supplies. (Batchelor, Calder, Sharma, DFID) Water audit
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Other options ► Plan B approaches If you cannot ration water, ration energy Gujarat restructuring of electricity grid ► Innovative legal instruments Regulating ET by banning transplanting in hottest season (Punjab, India)
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Exploring opportunities for “water savings” at system level is still worthwhile ► Water management is far from being moderately good everywhere ► IWRM will engineer “water scarcity” by decreasing allocations/abstraction ► More erratic supply (climate change) ► There will be financing and it should be put to good use if possible ► Some OFWM techniques do “save water” ► Adjust irrigation delivery service characteristics to new demands from lower levels to decrease their water use for various reasons, or allow them to adjust to lesser water allocations ► Economic opportunities
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MASSCOTE Modernizing Irrigation Management The MASSCOTE Approach— Mapping System and Services for Canal Operation Techniques Daniel Renault Thierry Facon Robina Wahaj
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Plan ► Generalities of demand management for irrigation ► Some difficulties ► Some recent approaches ► Conclusion
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► Issues for the future ► Water efficiency, food security, and rural development Our case studies have revealed a big variation in the economic value of water by sector and by region, low economic efficiency of agricultural water use, and poor cost-effectiveness of underground water withdrawal in North China. Although the general direction of improving water-use efficiency by reducing demand for water by the agricultural sector is supported, the issue is complicated by and associated with various issues involving the rights and well-being of the rural population, national food security, agricultural sector protection, and poverty alleviation. The central issue is how to reduce rural poverty and secure the nation’s food supply while at the same time improving the efficiency of water use. Any further policy recommendations have to address these concerns and will require further study. Our case studies have revealed a big variation in the economic value of water by sector and by region, low economic efficiency of agricultural water use, and poor cost-effectiveness of underground water withdrawal in North China. Although the general direction of improving water-use efficiency by reducing demand for water by the agricultural sector is supported, the issue is complicated by and associated with various issues involving the rights and well-being of the rural population, national food security, agricultural sector protection, and poverty alleviation. The central issue is how to reduce rural poverty and secure the nation’s food supply while at the same time improving the efficiency of water use. Any further policy recommendations have to address these concerns and will require further study.
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► Demand management strategies and instruments need to be effective and appropriate but seen in a broader context ► Decision-makers and users need to review broad social and economic and environment objectives through a water lens and improved understanding of water availability and use, to guide bulk allocation, sectoral policies, productivity targets and policy instruments and investments.
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► To arrive at a coherent and feasible set of policy goals, water resources management strategies and investment programmes, it will be important to focus on important policy dilemmas: Economic water productivity vs. equity and other strategic goals Resource use efficiency vs. resilience vs. redundancy National objectives vs. local and river basin objectives Water, energy and food nexus Managing informality of the water economies Political feasibility: ideal vs. second-best options Managing transitions: supporting resilience or a combination of improvements and exit strategies
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E-conference on www.asia-water.org
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