Hosepipe bans in force as drought declared - is your area affected?

Droughts have been declared across large parts of England and Wales as successive heatwaves have left water supplies under strain.

The Environment Agency (EA) has announced that more than half of England is now in drought, with central, eastern and southern areas most affected.

A drought has also been declared by Natural Resources Wales (NRW) in North Wales and the Upper Severn river basin.

Both England and Wales are on course to record the driest July on record, which - on top of hot, dry conditions in spring and early summer and increased demand - has left water supplies heavily depleted.

More than 20 million people in England and Wales have now been placed under a hosepipe ban.

This means hosepipes cannot be used for watering gardens, washing vehicles and windows and filling pools.

So how is your area doing and are you in a drought?

There is no single definition of drought, but it often begins with a period of low rainfall. As the ground dries out, crops and vegetation can begin to struggle. If dry conditions persist, rivers, reservoirs and groundwater levels can also fall, putting pressure on water supplies.

Environmental bodies in each UK nation decide whether to declare drought or water scarcity by assessing current water resources alongside weather forecasts.

Both drought and water scarcity can lead to hosepipe bans.

While drought is driven by prolonged dry weather, water scarcity occurs when demand for water outstrips the available supply. This summer, restrictions have been introduced in some areas to help manage high demand.

But while recent months have seen temperatures regularly exceed 30C, winter was much wetter than usual.

It has raised questions about how effectively water resources are being managed, and whether the UK is prepared for drier summers expected with climate change.

So far, eight UK water companies have announced hosepipe bans - seven are spread across central, southern and eastern parts of England, and one is in Wales.

In England, more than half of the country is now in drought. The areas affected are East Anglia, Hertfordshire and the whole of London, Thames Valley, Hampshire and the Isle of Wight, Devon and Cornwall, the West Midlands, and Wessex (covering Dorset, Somerset, Wiltshire, and South Gloucestershire).

Several other areas of England are in "prolonged dry weather" - the category below drought - while only Yorkshire and the North East remain in "normal" status.

Elsewhere, North Wales and Upper Severn are in drought, with the rest of Wales in prolonged dry weather.

There are no official droughts currently in Northern Ireland.

Scotland does not declare droughts but monitors "water scarcity". Several areas are now in the most extreme category of "significant scarcity".

Our three main sources of water are rivers, reservoirs and from deep underground.

Following the hot, dry weather, the EA has said nearly 80% of England's rivers are seeing flows below normal or lower.

Some river flows are around the lowest on record, including the River Thames at Reading and the River Cam at Dernford, Cambridgeshire.

"Without significant rainfall we could see increasing impacts on wildlife, agriculture and water resources as the summer progresses," said Steve Turner, a hydrologist at the UK Centre for Ecology & Hydrology (UKCEH).

When declaring drought in North Wales and Upper Severn, Natural Resources Wales said many river flows in the area are "exceptionally low" for the time of year, with some locations seeing record lows for July.

Meanwhile, reservoirs are a crucial part of water supplies and levels in Wales, Northern Ireland and Scotland were all normal or above expected in June, according to the latest available data.

But figures up to 21 July show England's reservoirs are below average levels for the time of year.

South-east England relies more heavily on groundwater than reservoirs.

Groundwater originates as rainfall and is naturally stored beneath the surface in the pore spaces and fractures in rocks.

In June, groundwater levels were generally at or just below normal, having been topped up by winter rainfall but depleted by a drier spring in most regions.

But water can flow more slowly through some rock types than others, sometimes taking years to fully respond to current conditions.

These groundwater stores "respond more slowly to changes in the climate than rivers, which is why they provide a useful buffer during periods of drought", said Prof Alan MacDonald of the British Geological Survey.

It is why groundwater droughts in the south of England generally take a longer time to develop but can be longer-lasting if they do occur.

Droughts are complex phenomena, driven by a mix of natural and human causes.

The Met Office expects the UK to experience drier summers on average in future as the world warms, though there has been no clear trend so far.

But rising temperatures can play a more direct role by drawing extra moisture from the soil via evaporation.

"A warmer atmosphere is thirstier for moisture and this can mean water in the soil, rivers and reservoirs are depleted more effectively, leading to more rapidly onsetting droughts, heatwaves and wildfires," said Richard Allan, professor of climate science at the University of Reading.

But there are other factors that determine whether dry conditions lead to water shortages, including how we use water.

In a landmark review into the water sector of England and Wales, water companies were criticised for historic underinvestment in water infrastructure.

As part of plans to address water shortages, the government and water companies are planning nine new reservoirs for England by 2050, in addition to one under construction at Havant Thicket in Hampshire.

But the Environment Agency has warned that measures to tackle water leaks and control water demand - potentially including hosepipe bans and more smart meters - may be needed in England too.

Water companies in Scotland, Wales and Northern Ireland - which are all public bodies or non-profit - also said they were taking steps to secure future supplies.

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