 reduction in industrial water use in the past decade. In Sydney, some 900 000 more inhabitants have not increased the total water used, due to falling industrial use and vigorous demand management initiatives changing domestic fittings and appliances to low water use. However, in transition economies, water use by industry is INFRASTRUCTURE TO 2030: TELECOM, LAND TRANSPORT, WATER AND ELECTRICITY - ISBN 92-64-02398-4 © OECD 2006 5. THE IMPACTS OF CHANGE ON THE LONG-TERM FUTURE DEMAND FOR WATER SECTOR INFRASTRUCTURE increasing and often use per unit of output is two to three times higher for the same product than in OECD countries. This is generally because these industries are not charged the full economic cost of the services. Similarly, there has been a trend for industries to utilise their own wastewater treatment systems, and in many cases recover waste resources or energy. In Europe and a number of developed countries, this is encouraged by legislation and a desire by companies to achieve environmental accreditation to ISO 14000 or equivalent. Groundwater is now an important component in Asian economies. A recent estimate has put the agricultural value at some USD 25-30 billion per annum (Shah, 2003, cited in Gleick, 2004). This far exceeds the economic value from surface sources. Table 5.9 shows the dependency on groundwater for a number of regions. Table 5.9. Groundwater extraction in selected regions Number of structures Average extraction Population dependent extracting groundwater per structure (m ³/yr) on groundwater (%) (thousands, 2003) India 19 000-26 000 7 900 55-60 Pakistan (Punjab) 90 000 60-65 China 3 500 21 500 22-25 58 000 12-18 Mexico 414 285 500 000 Source: Gleick, 2004. By volume, four countries account for more than 60% of the world's groundwater abstraction: India, China, Pakistan and the United States. These countries account for 75% of the agricultural usage. Data are, however, not as reliable as they are often for private well abstractions for individual farmers - thus agricultural use