Balancing future water supply and demand in Beijing

In a year with average precipitation, Beijing in China is just able to meet its current water demand. However, the shortfall by 2010 is expected to be between 1.18 and 2 billion cubic metres. The city will have to both cut demand and expand supply to meet the needs of its residents.

Beijing has been a city for around three thousand years, butthe booming economy is overstretching the capital’s water resources.Researchers from Tsinghua University in China havestudied the impact of the growing commercial, industrial and agriculturalsectors. Their work shows that available freshwater sources are barelysufficient for current demand and are inadequate for future development.

The resultsof many recent studies of Beijing’s water situation have been used in thisresearch, with the acknowledgement that many current statistics and projectionsare based on fairly simple analysis methods . The researchers stress that all these figures may change as more advanced methods, betterunderlying data, and more appropriate indicators are used.

Demandis already being managed through conservation, pricing and quotas. The BeijingMunicipal Water Conservation Office, established in 1981, leads waterconservation campaigns. For example, legislation is improving the efficiency offaucets, toilets,showerheads and washing machines. Beijing residents pay twice as much for theirwater as they did three years ago, and industrial, commercial and institutionalusers have quotas and pay on a block tariff system (so the more water they use, the more expensivethe water becomes).

Alternativewater supplies and non-traditional water sources have also been explored tovarious degrees. These include better water re-use, rainwater harvesting, and aplan to divert waterfrom the Yangtze River. The team’s findings confirm that:

• There is a deficit of available water resources, groundwater isoverused, and water quality has deteriorated.
• Water-use efficiency in Beijing is relatively low compared withdeveloped countries, so there is much room for improvement.
• Integrating water conservation and demand-side management withwater planning is necessary to fully balance water supply and demand.
• Annual precipitation has dropped, the renewal ofwater resources is restricted, and there is not enough water conservation.

Managing demand or increasing supply alone cannot succeed.More radical solutions are needed, which go beyond current efforts.Policymakers will need to work on three key areas:

• The pattern of demandneeds to be changed and moderated; at the same time, new supplies must beintroduced.
• Economic incentives shouldbe systematically examined and designed to realise the potential of waterconservation. These include conservation pricing and rate structures,information incentives, distribution or access to water-efficienttechnologies, and cash transfers and financing methods.
• A well structuredwater-use database should be created and more advanced forecasting methodsused in order to make reliable future decisions regarding water balance.