Low rainfall in recent months means large areas of Britain face drought this year, according to the government, which is staging a "drought summit" on Monday to decide what action to take.
"The south east of England is at a high risk of drought due to continued low rainfall and central, eastern and south eastern England are unlikely to see a full recovery from drought conditions during 2012," says Environment Agency chairman Lord Chris Smith.
In the Anglian region the five months from September to January were the driest ever, the agency says.
"Pressure on water resources looks set to increase over the next few months, so it is more important than ever that consumers, businesses and water abstractors use water wisely," said national drought coordinator Helen Vale.
The Department for Environment, Food and Rural Affairs, the host for Monday's summit, says water resources need to be managed effectively, given increasing pressure on water supply as a result of population increase, changing household usage patterns and climate change.
"Despite our reputation as a rainy country, we may face a future with less rainfall and less certainty about when that rain will fall," it says.
Organisations to be represented at the summit include water companies, the Environment Agency, Natural England, British Waterways and the Met Office.
Government statistics show that each person in Britain uses on average 150 litres of water daily, with the average household using over 100,000 litres of water every year.
Defra has unveiled several actions its wants people to take to use less water at home. Everyone should turn off the taps as appropriate when cleaning their teeth or washing fruit and vegetables, they should find ways of flushing less water down the toilet and people should take shorter showers, the department says.
New appliances should be water efficient and householders should act promtly to fix dripping taps, which can waste up to 15 litres a day.
Shower, bath and washbasin water can be re-used in the home and in the garden, such as for flushing toilets, washing the car, watering plants or even for the washing machine, according to the Defra campaign.
Ahead of the summit, Thames Water now believes there will be a drought in its area after below-average rainfall for 18 out of the last 23 months.
Flows in the River Lee, which goes through Hertfordshire and north east London, are only 24 percent of the long-term average for the waterway, said Richard Aylard, sustainability director for Thames Water.
The Angling Trust's chief executive Mark Lloyd said "The vast majority of people are unaware that we are in the middle of a crippling drought..
"River levels are lower in many areas than they were in 1976 and many rivers in the South East have dried up completely."
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