DROUGHT IN THE UK

Purpose

This Policy Position Statement (PPS) looks at the effect of drought on public water supplies, other water use, and the environment, and sets out the position of the Chartered Institution of Water and Environmental Management (CIWEM) on this issue.

CIWEM calls for

• Comprehensive drought planning by all those with an interest in the water environment – water companies, government bodies including regulators, other abstractors and businesses that rely on water.
• Adaptive drought legislation and management that reconciles the needs of the environment, people and businesses when water is short while maintaining public accountability.
• Clear information for the public and other water users explaining that droughts are natural and cannot be avoided, but that people can help to manage the effects of drought.
• Ways that people and businesses can save water in a drought to be set out clearly in a way that people can understand.
• Good communication between all those involved in drought management to minimise conflict and encourage effective management.
• Hosepipe bans and sprinkler bans to be applied early in a drought as a sensible way of reducing the demand for water to avoid more serious impacts on the environment or further restrictions on water supply.
• Hosepipe bans to be seen as an important drought management tool, and not as a failure. Water companies should not be penalised financially for appropriate use of hosepipe bans.
• Any additional drought measures such as further abstraction to be planned well in advance, with comprehensive environmental reports.
• Progressive use of drought measures such as restrictions on water use and additional abstraction as a drought progresses, reflecting the impact on people, businesses and the environment.
• Drought legislation and management to recognise the importance of water to farming and business.
• Imaginative mitigation of the impact of drought measures such as additional abstraction so that the effect on the environment is reduced as far as possible.
• Further research into long-term drought forecasting methods.
• Further research into the way that catchments and the environment respond during drought, and recover after drought.
• Further research into the impact of climate change on future droughts.

1. UK drought

Many people think that the UK is wet. Our temperate climate brings frequent rain, but the weather is very variable, with very dry spells possible at any time of year. A series of dry months starts to cause environmental stress, with low river levels and groundwater flows. Public water supply is designed to cope easily with a few months of dry weather, but prolonged droughts require careful management.

Long droughts are a feature of the UK climate. 1975-76 is perhaps the most notorious drought of recent decades. In England and Wales, two consecutive dry winters were followed by a very hot and dry summer in 1976. Many restrictions on water use were introduced, including rota cuts in South Wales and standpipes in parts of Devon. Many trees died from moisture stress and the hot summer led to many fires on moorland and heathland. The drought broke with an early autumn in September 1976.

Droughts are not confined to the drier parts of England. In 1995 a dry winter in the Pennines gave very low reservoir levels in parts of Yorkshire. Road tankers were used to bring water from Northumbria to Yorkshire. There were also widespread droughts in 1933-34 and throughout the 1880s.

The worst drought in Scotland in the last 30 years was in 1984 when five very dry months caused supply problems at a number of locations. The most recent drought was in 2003 when the dry summer was followed by an exceptionally dry autumn resulting in a number of reservoirs reaching very low levels.  The worst affected area was Tayside where two consecutive drought orders were granted during 2004 to allow reservoir levels to recover.

In 2006, hosepipe bans affected 16 million people in southern England and three water companies were granted powers to restrict non-essential use of water. Environmental impacts include fish deaths, reduced breeding of wading birds, and outbreaks of poisonous blue-green algae in rivers and lakes.

2. Planning for drought

It is not possible to avoid the impact of drought entirely, but we can work to make sure that the effect on the environment and on people is minimised. Water companies’ long-term planning should make sure that essential public water supply can be maintained through prolonged droughts by considering a wide range of possible drought conditions.

CIWEM supports the introduction in England and Wales of statutory water company drought plans. Drought plans should show the actions that water companies plan to take as a drought progresses, and help to strike the right balance between water supply and the environment. CIWEM believes that people should not expect an unlimited supply of water at all times, and that restrictions on water use such as hosepipe bans are part of a sensible range of measures that water companies should take. Water companies should not be criticised for the introduction of hosepipe bans where these are necessary, and there should be no financial penalty for appropriate use of restrictions.

CIWEM believes that water suppliers in Scotland and Northern Ireland should also prepare similar drought plans to make sure that they are ready for future droughts.

CIWEM believes that people throughout the UK are insufficiently aware both of the possible impact of drought and measures that they can take to help to reduce its effect. Understandably, water suppliers are reluctant to tell customers that there can be a risk to water supply. CIWEM believes that recent experience in south east England demonstrates that people do accept that drought is a natural hazard even in the UK. CIWEM recommends more work from water suppliers, regulators and Government to help to make people aware of the risk of drought.  The concept of security of supply needs to be understood as meaning security of supply for essential uses, not for all uses at all times.

Taking additional water from the environment is a valuable drought management option, but may also cause additional stress to the water environment at a time when plants and animals are already suffering from low flows. CIWEM believes that the additional impact should be mitigated wherever possible, and that drought plans should identify clearly the environmental impact of any drought measures. This may require additional environmental monitoring before and during droughts so that the impact can be evaluated fully.

3. Future drought

We know that there will be droughts in the future. Climate change is set to bring hotter, drier summers and wetter winters. This means that summer droughts seem certain to be more frequent. This could be particularly important for upland reservoirs in the north and west, many of which can reach very low levels in a hot, dry summer. The impact of climate change on long droughts is less clear.  If dry summers are separated by wet winters, lengthy droughts may become less frequent as short sharp droughts become more frequent.  But whilst on average winters may become wetter, some winters may be drier, and there is no guarantee that two-, three- (or more) season drought sequences will not occur.  If they do, the combined effect will be more intense than experienced previously.

CIWEM recommends that scientific studies of the likelihood and impact of climate change on the frequency and duration of future droughts, and of the response of social and environmental communities be continued, and that the results be widely disseminated. Water companies should build the findings of such work into their long-term water resources plans, but should also make sure that their drought plans can cope with a wide range of future conditions.

CIWEM supports further work on long-term drought forecasts. Drought management would be significantly easier with reliable long-range weather forecasts. At the moment, water resources managers have to take decisions under the assumption that the weather continues to be dry. Many of the steps taken turn out, with hindsight, to be unnecessary. Improved longer-term weather forecasts would help to improve decision-making during a drought.
 
June 2007

Note: CIWEM Policy Position Statements (PPS) represent the Institution’s views on issues at a particular point in time. It is accepted that situations change as research provides new evidence. It should be understood, therefore, that CIWEM PPS’s are under constant review, and that previously-held views may alter and lead to revised PPS’s.