water infrastructure, much of it in informal and low-technology groundwater pumping, some of which helps grow cheap crops exported from the developing countries to the developed world. Worryingly, much of this water use is unsustainable (New Scientist, 2006). Consumption rates reflect availability and continuity of supply, relative wealth including size of property, and to some extent correlate with climate. WHO/UNICEF specifies that reasonable access to water means at least 20 litres per person per day (1/h/d), accessible within 1 km of that person's dwelling. However, this is a bare minimum; 50 l/h/d are required to ensure health and hygiene (Stephenson, 2001). Per capita consumption rates of more than 500 litres per day used to be common in the United States, but this has now declined to below 400 litres, depending on the state. In most European countries the 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 consumption is between 100 and 200 1/h/d. In countries with only standpipe supplies, average per capita consumption rates are some 20-60 1/h/d. The question of what consumption rates are to be met and in what manner has a huge impact on the development of water resources and the nature of the services provided, as well as the financial and institutional implications for the country. Metering of domestic consumption is not applied globally even in the most developed countries, and evidence suggests that it may have only a limited effect on constraining long-term use. In the United States not all properties are metered; in the Netherlands and the United Kingdom some 20-30% are metered, with slightly more in Germany and Denmark and some 75% in Australia. In a survey of 27 major Asian cities with populations exceeding 1 million in 1996, the ADB found that 15 were fully metered, six had metering for less than 7% of the population, and virtually no metering existed in majo