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A Guide to Reduce Water Footp

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A Guide to Reduce Water Footp Water Footprint Network provides science-based, practical solutions and strategic insights that empower companies, governments, small-scale producers and individuals to transform the way we use and share fresh water within earth’s limits. Founded in 2008 by the University of Twente, WWF, UNESCO-IHE, World Business Council for Sustainable Development, International Finance Corporation, Netherlands Water Partnership and Water Neutral Foundation, we are a dynamic, international learning community. Working together with and supported by our partners worldwide, we drive action towards sustainable, efficient and equitable water use, build communities to escalate change in river basins, share knowledge and train practitioners to solve the world’s water crises. As the global leader in Water Footprint Assessment, we find solutions using a common methodology that interlinks water related issues and leads to strategic action for water stewardship, resource efficiency, fair allocation and good governance. Our data, tools and Global Water Footprint Standard bridge sectors and viewpoints, illuminate the path towards integrated water resource management and accelerate progress towards sustainable development. www.waterfootprint.org Authors: Ashok Chapagain, Ruth Mathews, Guoping Zhang April 2017 C&A Foundation is a corporate foundation, affiliated with the global clothing retailer C&A. It is working to transform the apparel industry into a fair and sustainable industry that respects the rights of workers, improves livelihoods and conserves the environment. It collaborates with key partners to achieve the best results and greatest long term impact. From farmers to factory workers, it helps build strong and resilient communities in all the countries we touch. The current study was funded by C&A Foundation and results will be used by C&A business. www.candafoundation.org http://www.c-and-a.com/ The results and findings of this report are based on scientific analysis done by Water Footprint Network. All the internal data from C&A are provided solely to be used in this report. The partners of the initiative consider it a living document that will be adapted to the circumstances based on new findings and concepts, future experiences and lessons learnt. 1 Introduction ....................................................................................................................... 3 1.1 Water and cotton in India ......................................................................................... 4 1.2 Water footprint ......................................................................................................... 6 2 Key stages in cotton farming ............................................................................................ 8 3 Farming type .................................................................................................................. 10 4 Land preparation ............................................................................................................ 13 4.1 Land levelling, contour and ridge farming .............................................................. 13 4.2 Reduced tillage system .......................................................................................... 14 5 Planting stage ................................................................................................................. 15 5.1 Selection of planting date ....................................................................................... 15 5.2 Seed selection ....................................................................................................... 16 5.3 Crop rotation .......................................................................................................... 17 5.4 Intercropping and green manure ............................................................................ 17 6 Growing stage ................................................................................................................ 19 6.1 Irrigation technologies ............................................................................................ 19 6.1.1 Surface flooding ................................................................................................. 21 6.1.2 Sprinkler irrigation .............................................................................................. 21 6.1.3 Furrow irrigation ................................................................................................. 21 6.1.4 Drip irrigation ..................................................................................................... 22 6.1.5 Subsurface drip irrigation ................................................................................... 22 6.2 Irrigation strategies ................................................................................................ 22 6.2.1 Full irrigation ...................................................................................................... 23 6.2.2 Supplemental irrigation ...................................................................................... 23 6.2.3 Deficit irrigation .................................................................................................. 23 6.3 Mulching ................................................................................................................ 24 6.3.1 Mulching applied at early crop growth stage ...................................................... 24 6.3.2 Mulching applied at late crop growth stage ........................................................ 25 6.3.3 Mulching materials ............................................................................................. 25 6.4 Nutrient management ............................................................................................ 26 6.4.1 Selection of nutrient type and quantity ............................................................... 26 6.4.2 Synchronised application ................................................................................... 27 6.4.3 Fertigation .......................................................................................................... 27 6.5 Pest control ............................................................................................................ 27 6.5.1 Pesticide selection ............................................................................................. 27 6.5.2 Integrated Pest Management (IPM) practice ..................................................... 28 7 Harvesting ...................................................................................................................... 30 7.1 Land maintenance - leaching ................................................................................. 30 8 Overview of agricultural practices and their impacts on the water footprint and crop yield .................................................................................................................................... 32 8.1 Agricultural practices that reduce the green water footprint ................................... 33 8.2 Agricultural practices that reduce the blue water footprint ..................................... 34 8.3 Agricultural practices that reduce the grey water footprint ..................................... 35 8.4 Agricultural practices that increase crop yield ........................................................ 36 References ......................................................................................................................... 38 1 Figure 1. Key stages and potential farming practices available to a cotton farmer. .............. 9 Figure 2. Icons used to indicate the impact on the green, blue and grey water footprint and crop yield. ............................................................................................................................. 9 Figure 3. Comparison between the grey water footprint and crop yield for conventional, organic and hybrid farms in three states in India. ............................................................... 12 Figure 4. Irrigation technology in the order of increasing investment and decreasing blue water footprint. .................................................................................................................... 20 2 Separating the lint from the boll, Vellitiruppur, Erode, Tamilnadu. Source: Indiawaterportal.org (July, 2012) Few industries have the impact that the textile sector has had on the world. Globally, an average of almost 10,000 litres of water is necessary to produce 1 kilogram of cotton fabric, with approximately 2,500 litres needed for a standard 250-gram cotton t-shirt 1. Water is a key natural resource for the textile sector as its supply chain is both dependent upon the availability and quality of water, and its use creates an impact on those water resources through consuming and polluting water. The textile sector increasingly faces water availability and quality issues in its global supply chain. Reductions in the consumption and pollution of water resources in cotton cultivation will lead to greater water security for farmers and are necessary for water use to be sustainable, efficient and equitable. The Water Footprint Network has been supporting C&A in developing a deeper understanding of water consumption and pollution arising from raw materials production and garment processing. This has been done through quantifying the water footprint of raw materials and processing, assessing
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