Dripping taps can waste thousands of litres of water

The Institute for Public Policy Research (IPPR) wants more water meters installed to avoid future shortages.

Researchers looking at sustainable development said demand would grow with climate change and population growth.

Last year, the South East County Leaders group criticised government house-building plans saying it would leave millions facing water shortages.

The South East has some of the highest rates of household water use in the country Louise Every, IPPR

The IPPR said Southern Water and Mid Kent Water were not expected to achieve a 50% metering rate until 2010.

And Sutton and East Surrey Water was forecast to achieve a metering rate of 44% by 2030.

Louise Every, researcher for the think tank, said: "The South East has some of the highest rates of household water use in the country.

"Getting people to pay for the water they use through metering is a fairer way to pay and will encourage people to use water efficient appliances in their homes," it said.

The IPPR report called for buildings regulations to be revised so all new homes meet a 20% reduction in water use, which it claimed could be achieved with water-saving household appliances.

'Water-saving targets'

Other options included grey water recycling - re-use of household water for low water-quality applications such as toilet flushing.

Researchers also wanted water-saving targets for water companies.

This month, two water companies in the region warned of shortages after low winter rainfall, Sutton and East Surrey Water and Southern Water.

Eight million people live in the South-East, one of the UK's driest regions.

And on Friday, the Environment Agency published a report warning about climate change and said some of the greatest extremes of British weather had occurred in the last decade.