Explainer

What is a drought, and what can be done to stop us running out of water?

Walking a dry bank of a tributary to the Dowry Reservoir, close to Oldham. Credit: PA

ITV News Digital Producer Suzanne Elliott


Britain might be famous for rainy days, but after a prolonged dry spell and record-breaking temperatures, parts of England are now officially in drought.

The drought was declared on Friday morning amid a four-day amber warning for extreme heat from the Met Office.

The National Drought Group - made up of government and agency officials, water companies and other groups such as the National Farmers’ Union (NFU) - declared drought in parts of the South West, parts of southern and central England, and the East of England on Friday.

Possible impacts of drought include stress on water supplies, localised wildfires, reduced crop yields, and an effect on wildlife.

What causes drought?

Drought occurs during a period of hot, dry weather and low rainfall, leading to a water shortage.

Unlike most other types of extreme weather, drought tends to build up over time and can last from as little as a few weeks up to several years, according to the Met Office.

The Intergovernmental Panel on Climate Change lists four common types of drought:

  • Meteorological drought – when rainfall in an area is below average for the region

  • Agricultural drought – when lack of rainfall or dry soil affects farming and crop growth

  • Ecological drought – like agricultural drought, but when lack of water affects the local environment as well

  • Hydrological drought – when water supplies such as streams and reservoirs are low, which can be caused by low rainfall, lack of snow melt, or other reasons

They can occur together or separately.

A view of the low water levels at the United Utilities, Woodhead Reservoir, in Derbyshire. Credit: PA Images

What happens when drought is declared?

Agencies and water companies must take action to manage water supplies and protect the environment.

In England, the main organisations responsible for managing water resources during drought are the Environment Agency, water companies, and the government.

A number of other authorities are also involved in the response, such as environmental groups and local councils.

The Environment Agency (EA) uses a green, yellow, amber and red colour-coded system to plan and manage drought.

Green is used for 'normal' situations, while yellow indicates a period of prolonged dry weather. Amber means drought, or recovering drought, and red means severe drought.

Water companies also have their own plans, where they must state what they will do to reduce the demand for water during a drought.

There are a range of actions that can be taken to protect water supplies when needed. These include limiting non-essential water use (e.g. hosepipe and sprinkler bans), reducing mains pressure, and preventing leakage.

Water companies can apply for a drought order to take more water, but must first demonstrate that they have made efforts to save it.

Water supplies need to be monitored during a drought. Credit: PA Images

Wildlife and ecosystems may need additional monitoring in a drought situation, particularly fish, who are at risk from low water levels and less oxygen in the water.

Vulnerable people are likely to experience adverse health effects and the wider population could also be affected.

Delays to travel are possible, and there is an increased risk of water accidents and fires as more people head to tourist spots.

Droughts are not classed as emergencies unless there is a serious threat of restrictions to public water supply, or a major incident requiring a multi-agency response, says the EA.

Will there be more hosepipe bans?

Months of little rainfall, combined with record-breaking temperatures in July, have left rivers at exceptionally low levels, depleted reservoirs and dried-out soils.

With at least six rivers (the Teign, Taw, Waveney, Soar, Asker and Rother) seeing the lowest flows of water since records began and the River Thames five miles shorter as its source dries up, companies are having to introduce water-saving measures, such as hosepipe bans.

Southern Water has already imposed a hosepipe ban for customers in Hampshire and on the Isle of Wight, which was followed a week later for South East Water customers in Kent and Sussex.

A person lying on scorched grass in Victoria Park, east London. Credit: PA Images

Welsh Water has also announced a ban for Pembrokeshire and Carmarthenshire later this month. Rule-breakers face fines of up to £1,000 if taken to court.

Environment Secretary George Eustice has urged more firms to take action to mitigate the effects of the prolonged dry weather.

But as each water company has different thresholds - and demands - we might not see a UK-wide ban.

A spokesperson for industry body Water UK said companies are working to minimise the need for restrictions – for example, by changing their sources of water to reduce pressure on hot spots, and moving water around a region to provide to areas under pressure.

How have we reached this stage?

Put simply, it hasn't rained enough, and prolonged dry weather brings other issues.

This July was the driest in England since 1935, according to the Met Office, compounding problems caused by what had been the driest first half-year since the 1970s.

During times of hot, dry weather, demand for water goes up, with people washing more, watering their plants, and using water outside in, for example, paddling pools.

A temporary hosepipe ban restricts people from using hosepipes or sprinklers to water private gardens or wash cars. Credit: PA

Figures from industry body Water UK found that during the recent heatwave, levels of water demand exceeded all records, increasing by 40% in some areas when temperatures exceeded 40C.   

With the Met Office warning that there is “very little meaningful rain” on the horizon for parched areas of England as temperatures are set to climb into the 30s this week, the risk of drought and the need for water restrictions increases.

Droughts aren't unusual in the UK. Alastair Chisholm, Director of Policy, at CIWEM said they are part of the British climate but that a dry winter has made this year's "particularly extreme".

"The key to droughts is winter rainfall which normally recharges reservoirs, aquifers and rivers. We had a quite dry winter (particularly in the south-east), a dry spring and then a record dry July exacerbated by record heat," he said.

When was the last drought in the UK?

The last time drought was declared was in 2018.

Other notable droughts took place in 1975 to 1976, 1989 to 1992, 1995 to 1996, 2004 to 2006 and 2010 to 2012.

A severe drought occurred from May 1975 to August 1976, when a dry winter in 1975-76 was followed by an intensely hot, dry summer.

The scene outside the Tollington Arms in Holloway, north London, after a 36in water main burst, causing flooding up to four feet deep Credit: Jonathan Brady/PA

What about leaks?

We lose around three billion litres of water a day from leaks. The amount might sound shocking but England is actually seeing the lowest ever leakage in history, with leaks having reduced by over a third since the 1990s.

Southern Water’s annual report showed it is wasting nearly 21 million gallons of water a day due to leaks, though this is a slight reduction on the previous year.

Water UK said teams are increasingly using advanced technology, such as AI and drones, to detect leaks, and new advanced techniques to repair them quickly – sometimes without even needing to dig up the road.

There are also, they say, "large numbers of extra people out repairing leaks" particularly as dry ground can press on pipes and cause them to crack.

Provisional figures from Ofwat from July showed three-quarters of water companies were meeting leakage targets and some have reduced leakage by more than 10% over the past two years. But there is still clearly a lot of work to do to halve leakage by 2050, in line with targets.


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Could the UK run out of water?

Hotter, drier summers caused by climate change as well as an increasing population mean there is a risk of water shortages by 2050, Water UK said.

The National Infrastructure Committee (NIC) has said water needs to start being managed better across the UK, otherwise the country could face a future of queueing for emergency bottled supplies "from the back of lorries".

The water industry is adapting to changing the climate to tackle more dry summers and droughts with 18 major, long-term projects, such as new reservoirs currently planned in a bid to water-proof the future.

The Rivers Trust said wider action needs to be taken - and quickly to combat future droughts. It is calling for accelerated metering, support for households to reduce water usage, such as installing low flow toilets and water butts, and sustainable drainage including rain gardens, wetlands and permeable paving to build up local stores of water underground.

Spain is the driest it's been for over a thousand years, according to a recent study and such is the scarcity of water, that usage is policed in parts of the country.

Could we see that here, on our once damp island?

It is not inconceivable. Water companies are already warning there needs to be sufficient rain this autumn and winter – when less is absorbed by growing plants – in order to recharge groundwater and reservoirs before next year, and that a second dry winter could significantly worsen the situation.