Lake Vyrnwy Nature Reserve and
Estate ( ) ([pronounced [E]VURN-OI]) is an area of land in
Powys, Wales, surrounding
the Victorian reservoir of Lake Vyrnwy.
, built in the 1880s, is the
first of its kind in the world. The Nature Reserve and the area
around it are jointly managed by the Royal Society for the
Protection of Birds
, and Severn Trent
. It was built for the purpose of supplying
Liverpool and Merseyside with fresh
water. It flooded the head of the Vyrnwy Valley and submerged the small village of
Today it is a popular retreat, for people in the
for days out, and also for ornithologists, cyclists, and hikers.
The Reserve is designated as a National Nature Reserve
, a Site of Special Scientific
, a Special
, and a Special Area of
The Dam looking East, showing
compensation water being released from the reservoir
Water flowing over the crest of the
Rhiwargor Falls on the Lake Vyrnwy
Dr George Deacon (1843-1909) started the design of the Vyrnwy Dam
in 1879 at the age of 36. Following Vrynwy Dr Deacon founded his
practice in London in 1890 which subsequently became Sir Alexander
Binnie Son & Deacon, Binnie and Partners, and finally Black
Dr Deacon was instructed to prepare the Parliamentary Plans for the
scheme in 1879. The Dam
construction started in
1881 and was completed seven years later in 1888. It was the first large
stone-built dam in the United Kingdom, and is built partly out of great blocks of
When built it cost £620,000, which today
is around £22,000,000. The dam is high from the bottom of the
valley, and thick at the base. The dam's length is , and has a road
bridge running along the top. It is decorated with over 25 arches
and two small towers (each with four corner turrets) that rise
above the road surface.
Vyrnwy was the first dam to carry water over its crest instead of
in a channel at the side. At the bottom of the dam is a body of
water known as the Stilling Basin, this is necessary to absorb the
energy when the water flows over the crest and into the valley, and
stops the water from eroding the foundations of the dam.
Underneath the West Tower is a building known as the Power House.
Inside is an electrical
which is driven by water leaving the reservoir.
Before mains electricity
in the 1960s this was Llanwddyn's only source of power.
The West and East Towers release compensation water by huge valves,
which are controlled by Severn Trent
. This water is purely for the River Vyrnwy, which would otherwise dry out unless in
Depending on the Water Levels downstream Severn Trent
release anything from 25 to 45 megalitres (5.5 to 10 million
gallons) of compensation water into the river Vyrnwy each day. Only
a few hundred yards downstream is a weir, which the Environment Agency
use to measure the
daily amount of compensation water. This weir also holds back
enough water to create the stilling basin.
Earlier dams in Britain had been built by making great earth
embankments to hold back the water. This new type of stone dam
would change the face of the Welsh landscape over the coming years.
stone dams to be built in Wales on an even bigger scale than Vyrnwy
were those built in the Elan Valley. 1
The Straining Tower and Aqueduct
Approximately from the dam is the reservoir's straining tower.
only from the shore its purpose is to filter or strain out material
in the water with a fine metal mesh, before the water flows along
the aqueduct to Liverpool.
Its architecture is Gothic
and built during the same time as the
dam. The tower as a whole is tall, of which is underwater. The
other is above water, and is topped with a pointed copper clad
roof, which makes it look light green.
The sixty-eight miles of aqueduct bring water from Lake Vyrnwy to
Liverpool, and are part of extensive works that also involve
Britain's first high masonry dam at Vyrnwy.
The aqueduct originally consisted of two pipelines, made largely of
. To help maintenance work on the 9 ft
diameter cast-iron tunnel which took the aqueduct under the
Mersey, riveted steel piping was also used.
was an early use of the material which was to become the norm for
trunk water mains piping.
Brick and concrete lined tunnels carried pipes at Hirnant, Cynynion
and Llanforda, and a fourth later added at Aber so that the Hirnant
tunnel could be made accessible for maintenance. The first section
of a third pipeline was laid in 1926-38 using bituminous-coated
steel. To increase capacity, a fourth pipeline was added in
Re-organisation of the pipe crossings beneath the Mersey and the
Manchester Ship Canal
undertaken in 1978-81. The current provision relies on three, 42in
diameter pipes delivering up to 50 million gallons per day into
reservoirs at Prescot, east of
The aqueduct carrying water away from Lake Vyrnwy to Liverpool was
constructed across the valley from the reservoir between 1881-92.
It crosses the valley floor near Penybontfawr and then runs north
and Efail-rhyd on the north-east of the Tanat Valley
. The aqueduct is largely hidden
from view although there are a number of visible surface features
including air valves, the Cileos valve house, the Parc-uchaf
balancing reservoirs, and a deep cutting to the west of
Llanrhaeadr-ym-mochnant. In terms of the history of roads in the
Tanat Valley it is interesting to note that complaints were made
about damage to local roads during the construction of the Lake
The reservoir is Severn Trent
's largest. When full, it can take as much as up to , and
it covers an area of of land, the equivalent of around 600 football pitches
. The lake has a circumference
of with a road that goes all the
way around it. Its length is . On a clear day the lake, along with many
others in North
Wales, can be seen from space.
There are 31 streams, waterfalls, and rivers that flow into the
lake. Some are no more than a trickle, while other waterfalls
cascade down the mountains. The 6 rivers that flow into the lake
are all named respectively to the mountains or hillside it flows
from. From the west side of the dam, clockwise, their names
- Afon Hirddu
- Afon Eiddew
- Afon Naedroedd
- Afon Cedig
- Afon Y Dolau Gwynion
On the Northern Edge of the lake is a small hamlet called Rhiwargor
where the rivers Afon Eiddew
meet. Up the valley of
Afon Eiddew, there is an impressive waterfall, one of the largest
surrounding the lake. Known locally as Pistyll Rhyd-y-meincau
, it is
commonly known as Rhiwargor
shortly after completion, the lake was stocked with 400,000
continues to supply Liverpool with fresh water.
It is also the water source used in the manufacture of Bombay Sapphire
Nature Reserve & Conservation
Lake Vyrnwy is a Nature Reserve
has several bird
around the lake, where several rare species of bird are
known to be breeding, such as the Peregrin Falcon
, the Pied Flycatcher
. They host every spring a
Around 90 species of bird have been recorded to be breeding on the
reserve, and six species of bat, including the pipistrelle
and brown long eared bat. Butterfly
species include Purple Hairstreaks,
commas, and peacocks. Dragonflies
include Golden Ringed, Common Hawker and Four spotted chaser.
They are restoring the Heather Moorland
that grows on the mountains around the
lake. This restoration of heather moorland is becoming increasingly
common in Britain. The heather is usually burnt, cut, and the seeds
collected to be sowed where the heather has gone. This management
of the moorland helps improve the habitat for Red Grouse
and the Short-eared Owl
. Sheep, cattle and ponies
also graze on the heather.
Broadleaf trees are being planted in replacement of coniferous
trees, and even manmade things are
being restored, such as hedgerows
walls. Wild flowers areas are
also being restored to help insects, birds, and other
Llanwddyn has had since 1995 a sculpture trail in the valley below
the dam. This Sculpture Park, started by local artist Andy Hancock
contains dozens of wooden carved
sculptures. All from individual sculptors, who have come from as
far a field as Australia
, and Eastern Europe
. There are many other
sculptures placed at picnic sites around the lake itself. For
instance, there are large wooden picnic benches in the shape of
leaves and trees on the west side of the lake at Llechwedd Ddu.
Near the Old Village on the beach is a sculpture of dolphins, which
when the lake rises in a flood, gives the impression that they are
jumping out of the water. Several totems
be seen carved into standing trees. many others have been carved
from fallen trunks and been erected again.
Activities in the area include sailing, hiking on Glyndwr's Way, rock climbing,
cycling and horseback riding.
There is also a half-marathon
located here every year, the Vyrnwy
The River Vyrnwy
The River Vyrnwy (or Afon Efyrnwy
in Welsh) runs from the
Welsh mountains; its sources are from many and varied streams and
tributary rivers from around the lake. However, since it was
flooded, the river starts at the foot of the dam and flows east
towards England, eventually finding its way to Shropshire where it converges with the River Severn near the village of Melverley on the Welsh border.
The river runs for ;
the last 8 miles forms a natural boundary between England and
Wales. The River Severn
then takes its course though England to the Bristol Channel.
The Met Office
has a weather observation
outpost at Lake Vyrnwy. Updated hourly, it observes the local
temperature, wind direction and wind speed, air pressure and
The local district Football Club is Llanwddyn FC