A Comprehensive Introduction to Water Footprints
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A Comprehensive Introduction to Water Footprints Arjen Hoekstra Professor in Water Management – University of Twente – the Netherlands Scientific Director – Water Footprint Network www.waterfootprint.org Overview Presentation 1. The water footprint of products 2. The relation between consumption, trade and water 3. The water footprint of a business 4. From concept to practice Water footprint impact assessment Reducing and offsetting water footprints 5. Conclusion 6. The way forward 1 The water footprint of products Water footprint of a product ► the volume of fresh water used to produce the product, summed over the various steps of the production chain. ► when and where the water was used: a water footprint includes a temporal and spatial dimension. ► type of water use: green, blue, grey water footprint. Water footprint of a product Green water footprint ► volume of rainwater evaporated. Blue water footprint ► volume of surface or groundwater evaporated. Grey water footprint ► volume of polluted water. 0.16 1.07 Cotton seed oil, Cotton seed oil Production chain 0.47 1.00 refined cotton Hulling/ 0.51 Cotton seed Cotton seed extraction 0.33 cake 0.63 0.18 0.10 Cotton linters 0.20 Harvesting Cotton plant Seed-cotton Ginning 0.05 0.35 0.10 Garnetted stock 0.82 1.00 Cotton, not Carding/ Cotton lint 1.00 carded or combed Spinning 0.95 Cotton, carded or 0.99 combed (yarn) Knitting/ weaving 0.95 0.05 0.99 0.10 Grey fabric Yarn waste Wet processing 1.00 1.00 Fabric Legend Finishing 0.35 Product fraction 1.00 1.00 0.82 Value fraction Final textile [Hoekstra & Chapagain, 2008] Water footprint of EU’s cotton consumption (blue water) 421 Mm3/yr 2959M m3/yr 581 Mm3/yr 803 Mm3/yr 450 Mm3/yr 533 Mm3/yr 690 Mm3/yr 2459 Mm3/yr Blue water footprint Million m3/yr EU25's impact on blue water resources [Hoekstra & Chapagain, 2008] Water footprint of EU’s cotton consumption (green water) 485 Mm3/yr 165 Mm3/yr 325 186 3 Mm /yr Mm3/yr 283 Mm3/yr 3467 Mm3/yr Green water footprint Million m3/yr EU25's impact on green water resources [Hoekstra & Chapagain, 2008] Water footprint of EU’s cotton consumption (grey water) 92 310 Mm3/yr Mm3/yr 635 Mm3/yr 102 Mm3/yr 398 3 83 Mm /yr Mm3/yr 409 Mm3/yr 697 Mm3/yr Dilution water footprint Million m3/yr EU25's impact on global water resources due to pollution [Hoekstra & Chapagain, 2008] The water footprint: making a link between consumption in one place and impacts on water systems elsewhere Shrinking Aral Sea The water footprint: making a link between consumption in one place and impacts on water systems elsewhere Endangered Indus River Dolphin [Photo: WWF] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] [Aldaya & Hoekstra, 2009] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] [Hoekstra & Chapagain, 2008] Water footprint of biofuels from different crops [litre/litre] [Gerbens-Leenes, Hoekstra & Van der Meer, 2008] 2 The relation between consumption, trade and water Water footprint of a nation ► total amount of water that is used to produce the goods and services consumed by the inhabitants of the nation. ► two components: • internal water footprint – inside the country. • external water footprint – in other countries. Water footprint of a nation ► National water footprint = national water use + virtual water import – virtual water export National water accounting framework Virtual water Water use Virtual import for re- + for export = water Export export export + + + External Internal Water water + water = footprint Consumption footprint footprint = = = Virtual Water use Virtual + = water within water import country budget Import The traditional statistics on water use Production Regional virtual water balances (only agricultural trade) Arrows show trade flows >10 Gm3/yr [Hoekstra & Chapagain, 2008] Global average water footprint water average Global Water footprint per capita Water 3000 Domestic water consumption Industrial goods Agricultural goods 2500 2000 /cap/yr) 3 1500 1000 Water footprint (m footprint Water [Hoekstra & Chapagain, 2008] & Chapagain, [Hoekstra 500 0 Italy USA India Brazil China Japan Russia Mexico Nigeria Thailand Pakistan Indonesia Global water footprint of the Netherlands 82% of the Dutch water footprint is outside its own borders [Hoekstra & Chapagain, 2008] Environmental Water Scarcity Index Water stress (withdrawal-to-availability) < 0.3 0.3 - 0.4 0.4 - 0.5 0.5 - 0.6 0.6 - 0.7 0.7 - 0.8 0.8 - 0.9 0.9 - 1.0 > 1.0 [Smakhtin, Revenga & Doll, 2004] The impact of the water footprint of the Netherlands: hotspots 6 3 External water footprint for agricultural products (10 m ) Main product category in hotspot 0 - 10 Fruit, nuts and wine 10 - 100 Oil crops and oil from oil crops 100 - 1000 Coffee, tea, cocoa and tobacco > 1000 Livestock and livestock products Hotspots Cotton products 3 The water footprint of a business Water footprint of a business Operational water footprint • the direct water use by the producer – for producing, manufacturing or for supporting activities. Supply-chain water footprint • the indirect water use in the producer’s supply chain. The virtual water chain Virtual Virtual Virtual water water water flow Food flow flow Farmer processer Retailer Consumer green blue blue blue grey grey grey water grey and water water water water water water blue use use use water use [Hoekstra, 2008] The water footprint of a retailer Virtual Virtual Virtual water water water flow Food flow flow Farmer processer Retailer Consumer green blue blue blue grey grey grey water grey and water water water water water water blue use use use water use Supply chain WF Operational WF End-use WF of a product [Hoekstra, 2008] 4 From concept to practice From water footprint accounting to policy formulation Vulnerability of local water systems Current water stress in the places where the water footprint is localised 1 2 3 Spatiotemporal- Impacts of the Reduce and explicit water water footprint offset the footprint of a • environmental negative impacts • product • social of the water • individual • economic footprint • community • business [Hoekstra, 2008] Water footprint impact assessment Global map of where Global map of where the water footprint water systems are is located stressed Overlay Global hotspot map Hypothetical example Global water footprint of a business Environmental water scarcity located in the Netherlands Water stress (withdrawal-to-availability) < 0.3 0.3 - 0.4 Main producing regions Producing countries 0.4 - 0.5 0.5 - 0.6 0.6 - 0.7 0.7 - 0.8 0.8 - 0.9 Hotspots 0.9 - 1.0 > 1.0 Hotspots are spots where (1) the business has a substantial water footprint (2) water is stressed. Main producing regions Hotspots Reducing and offsetting the impacts of water footprints Reduction: all what is ‘reasonably possible’ should have been done to reduce the existing water footprint; do not undertake water-using activities if better alternatives are available. Offsetting: the residual water footprint is offset by making a ‘reasonable investment’ in establishing or supporting projects that aim at a sustainable, equitable and efficient use of water in the catchment where the residual water footprint is located. [Hoekstra, 2008] Shared responsibility and an incremental approach Consumers or consumer or environmental organizations push businesses and governments to address water use and impacts along supply chains. Some businesses act voluntarily in an early stage. Governments promote businesses in an early phase and implement regulations in a later phase. 6 The way forward www.waterfootprint.org Mission: Promoting sustainable, equitable and efficient water use through development of shared standards on water footprint accounting and guidelines for the reduction and offsetting of impacts of water footprints. Network: bringing together expertise from academia, businesses, civil society, governments and international organisations. Status today: 29 partners from six continents .