67 India’s Water Demand Scenarios to 2025 and 2050: A Fresh Look 1 Upali A. Amarasinghe, 2 Peter G. McCornick and 3 Tushaar Shah 1 International Water Management Institute (IWMI), NewDelhi, India 2 International Water Management Institute (IWMI), Colombo, Sri Lanka 3 International Water Management Institute (IWMI), Anand, India Introduction India is a vast country and its water supply varies significantly across regions and river basins. Water is plenty in the northeast (Brahmaputhra and Meghna basins), but few people live there, and land availability and food production is low. In the northwest most of the water resources are diverted for crop production to the extent that this region supplies food to the deficit regions of the country making it the largest provider of virtual water, that is water embedded in food, in the county (Amarasinghe et al. 2005). Water is scarce in the south and west of the country as the naturally drier areas come under increasing demand, and the aquifers have low storage capacity. Much of the runoff in the peninsular river basins is from the highly variable monsoon, which means it occurs during the 2 to 3 months of monsoonal rains. Thus, the regional water availability vis-à-vis changing water demand patterns and the determinants of these changing growth patterns are particularly important factors for medium to long-term water investment strategies in general in India, and in particular in the water-scarce peninsular river basins. This report examines the implications of future water supply demand of India under business as usual (BaU) scenario trends of key water demand drivers and also under possible divergences. The assumptions of the growth of key drivers in the BaU scenario (Annex 1) in this paper significantly differ from the assumptions of the scenarios of the NCIWRD (discussed in detail in Paper 2). The BaU scenario considers the year 2000 data as the base year and the trends in the 1990s for its demand projections whereas the NCIWRD scenarios considered 1993/94 data for the base year and the trends in 1980s for determining the key drivers. This report, which is primarily, based on the studies by Amarasinghe et al. 2007a and 2007b, • gives an overview of the business as usual (BaU) scenario food and water demand up to 2025/2050 in India; • discusses the past trends of key determinants or ‘drivers’ of water and food demand; and