Purpose
This Policy Position Statement discusses the causes of drought
in the UK, how we can plan for drought and sets out the position of
the Chartered Institution of Water and Environmental Management on
this issue.
CIWEM calls for:
- The continuation of 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. These should be updated as
circumstances dictate, even during a drought if planned actions
turn out not to be the most sensible solution, or as a new option
comes to light.
- 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.
- Restrictions on water use for non-essential purposes
(appropriate to the level of drought severity) to be considered
early in a drought, as a sensible way of reducing the demand for
water to reduce the likelihood of more serious impacts on the
environment or further restrictions on water supply.
- Temporary 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 these restrictions. However,
water companies should take into account the significant cost of
such restrictions on some users.
- Drought legislation and management to recognise the importance
of water to farming and business.
- Consideration of need for a 'Drought Monitoring System', to
complement and enhance the European Drought Alert System (similar
to that which exists in the US), to improve preparedness and
response to droughts (cf. the England & Wales and Scottish
national flood forecasting centres).
- 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.
- Support for further scientific research on delivering
improvements in seasonal forecasting, soil moisture monitoring
systems and developing climate services, together with better
mechanisms to ensure rapid uptake of this science into drought
management and public information systems.
- Further research into: long-term drought forecasting methods;
the way that catchments and the environment respond during drought,
and recover after drought; the impact of climate change on future
droughts.
UK drought
Many people think that the UK is wet. It is in parts; however
the amount of rainfall per capita is low in some areas of the
country. Our temperate climate brings frequent rain, but the
weather is very variable, with very dry spells possible at any time
of year. For much of the country, low rainfall in winter rather
than summer is the key determinant of potential drought as winter
rainfall is critical for recharging aquifers that are important for
maintaining river baseflows in the following summer. A series of
dry months starts to cause environmental stress, with low river
flows and groundwater levels. 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 a very wet autumn in 1976.
Droughts are not confined to the drier parts of England. In 1995
a dry winter in the Pennines gave rise to 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.
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. Drought planning is undertaken to a varying
extent by a range of organisations within England and Wales,
including the Environment Agency, the water industry and other
parts of the water sector, including those with responsibility for
navigation, power generation and agriculture, all of whom have an
interest in managing the impacts of droughts. Water companies'
drought planning should make sure that essential public water
supply can be maintained through prolonged droughts by considering
a wide range of possible drought conditions.
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 impact on 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 Temporary
Bans are part of a sensible range of measures that water companies
should take. Water companies should not be criticised for the
introduction of temporary water use bans where these are necessary,
and there should be no financial penalty for appropriate use of
restrictions. Temporary Bans include restrictions on hosepipes and
sprinklers to wash cars and for garden watering, for filling pools
and outdoor cleaning.
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 alarm their customers but it is
important to understand 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, during and after droughts so that the impact can be
evaluated fully.
Future drought
We know that there will be droughts in the future. Climate
change is expected to bring hotter, drier summers and wetter
winters. This means that summer droughts seem very likely 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, long lasting 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 and adequate
funding to deliver these plans should be provided by Ofwat, but
should also make sure that their drought plans can cope with a wide
range of future conditions. Similarly, other parts of the water
sector with a responsibility or need to plan for droughts should
take account of such studies and research.
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
although drought management will still need to plan for the worst
case scenario. CIWEM supports further work on long-term drought
forecasts.
February 2012
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.
