13-Jul-2006
- The Environment Agency announced on the 13 July
2006 that, for the first time in 10 years, the
Shropshire Groundwater Scheme is being used to
support river flows in the River Severn.
This will help to safeguard
public water supplies, while ensuring sufficient
water is available for the environment.
As a result of falling water
levels in Clywedog Reservoir, Phases 2 and 3 of
the Shropshire Groundwater Scheme were put on
standby in late June. Both phases were switched
on this week, pumping approximately 100 Megalitres
a day into the River Severn to maintain water
levels. That is the equivalent of about 10 million
buckets of water a day.
Phase 2 of the groundwater scheme
covers the Montford Bridge area west of Shrewsbury.
Phase 3 covers the Bomere Heath area north west
of Shrewsbury. In both cases, water is pumped
from boreholes which feed pipelines which, in
turn, discharge into the Rivers Severn and Perry.
Environment Manager, Bob Harvey,
says: "This is the first time in about 10
years that we have needed to use water in the
rocks below Shropshire to support the River Severn.
We are doing this now to protect the water stored
in Clywedog Reservoir for use later in the summer
if the dry weather continues. Based on current
predictions, we expect to be using the Shropshire
Groundwater Scheme to support the river for the
next four weeks.
"Experience in the southern
part of the country this year has shown how vulnerable
we are to prolonged periods of low rainfall. The
Shropshire Groundwater Scheme is part of our long-term
solution to this problem in the Midlands and uses
the natural water resources in the rocks beneath
our feet to support flows in the River Severn
during dry spells. It helps to safeguard future
water supplies for homes and families, as well
as farming and industry, whilst still protecting
the environmental requirements of the river itself.
"Everyone can help us to
conserve water by using less. Even small things
like turning off the tap when you brush your teeth
add up to a lot of water saved if we all do it.
Take showers instead of baths, put a water saving
device in your toilet cistern. Water is a valuable
resource. There is so much each of us can do,
especially during this dry weather, to help our
water resources go further."
Notes to Editors
Shropshire Groundwater Scheme
The Shropshire Groundwater Scheme
is being developed across North Shropshire and
allows for the staged construction of up to eight
independent phases, to be built as and when the
demand for water increases.
Construction began in 1982.
By 1999 the first three phases had been commissioned.
Phase 4 has now been commissioned, increasing
the total combined yield of the scheme to 190,000
cubic metres of underground water a day. Phase
5 is under development but the demand for water
has not yet justified the construction of Phases
6, 7 and 8.
The Groundwater Scheme boreholes
are used only for short bursts during periods
of prolonged low rainfall. We estimate that, based
on data for the past 50 years, the Scheme will
operate in about two of every five years, averaging
between five and fifteen weeks pumping per year.
The scheme has been needed in
5 separate years (1984, 1985, 1989, 1995, and
1996). In all other years water from the storage
reservoir at Llyn Clywedog has been enough to
maintain water supplies in the River Severn.
Groundwater – the hidden asset
The importance of groundwater
is easily overlooked, as it is an out-of-sight,
and all too often out-of-mind, asset. In the UK,
groundwater provides approximately 30% of the
public water supply in England and Wales, 7% in
Northern Ireland and 3% in Scotland.
Much of North Shropshire is
underlain by extensive red, water-bearing sandstone
bedrock, called aquifers. Replenished annually
by winter rainfall the highly porous nature of
these rocks means that they are able to store
huge quantities of water underground. This makes
the Shropshire sandstone aquifer an ideal alternative
to conventional surface water reservoirs for supporting
river flows.
The Shropshire Groundwater Scheme
was devised to work in conjunction with the Clywedog
and Vyrnwy reservoirs to meet rising demands for
water. The Scheme abstracts groundwater via large
diameter boreholes drilled deep into the sandstone
aquifer.
Pumped groundwater is delivered
through a network of buried pipelines, either
directly to the River Severn or via one of its
major tributaries such as the Rivers Perry, Roden
or Tern.
Advantages of the Scheme over
a conventional surface water reservoir lower construction
costs – the Groundwater Scheme cost £20million
to build, compared with £110 - £120
million for a reservoir.
Phased construction eliminates
premature expenditure
Location complements existing
storage components
Lower land uptake: the Scheme
occupies less than 10 hectares compared to 250
hectares flooded behind a Clywedog-sized reservoir.
Reduced visual impact: the majority
of the infrastructure is located below ground
level and therefore out of sight.
Management of water resources
The Environment Agency is one
of Europe’s largest environmental protection bodies.
Amongst our many duties, we are responsible for
securing the sustainable management of water resources
including:
controlling water usage through
abstraction licensing
artificially maintaining river
flows through controlled releases of surface and
groundwater resources.
Our overall aim is to balance
the demands of water consumers whilst ensuring
that sufficient resources are available for the
environment.
Lyn Fraley
